SONS EUROCORES: Proposal 05-SONS-FP-014 Liquid Crystal Nanoparticles - LC-NANOP
Lead Research Organisation:
University of York
Department Name: Chemistry
Abstract
Liquid crystals (LCs) are the quintessential, self-organising, molecular materials of the modern era. The ease with which they can be reoriented in electrical, magnetic and mechanical fields has led to a plethora of applications, resulting, for example, in the dominance of the electro-optic displays market. Most LCs have been designed as either low molar-weight materials for displays (eg 4-alkyl-4'-cyanobiphenyls) or high molecular-weight materials for high yield-strength polymers (eg KevlarTM, and VectraTM). In contrast to existing materials, nano-structured LCs can combine self-organisation with the ability to form secondary and tertiary structures, in a structural hierarchy similar to that found for proteins. Furthermore, super- and supra-molecular LCs can exhibit a variety of physical properties which make them attractive for applications in the fields of nano-science, materials and biology. We predict that future materials research and applications of LCs will be focused on a variety of exciting topics, which reflect our ability to control self-organising, self-assembling and micro-segregating processes of complex/giant molecular systems to yield addressable, self-organised nano-structures. The materials themselves will be property designed and synthesised with smart and often multifunctional characteristics. Their applications will spread across the boundaries from advanced technological devices through to smart bio-materials/sensors, even to the discovery of new states of matter . Anticipating such exciting developments, we intend to utilise the unique self-organising abilities of LCs in a bottom-up approach to the creation of ordered arrays of nano-particles, rather than the currently used, but self-limiting, top-down methodologies (eg nanolithography). In taking this approach, we will be able to prepare liquid-crystalline nano-particles with hierarchical hybrid structures with specific built-in functionality. The primary challenges in this programme are the rational design, synthesis (pure and/or with up-scaling) and characterization of super- and supra-molecular materials with in-built functionalities, which will self-organise and/or self-assemble in order to yield novel materials or states of matter of practical importance. Thus, the liquid-crystalline nano-particles will be designed, with the aid of simulations, in the form of a nano-particle (eg, silsesquioxanes, carbosilanes gold, silver, titania, viruses and spores etc) as the central scaffold, and where the scaffold may be multilayered. Surrounding the scaffold is a liquid-crystalline coat , which may be derived from spherical, disc- or rod-like mesogenic units. The external coat may consist of one or more mesogenic layers, which in turn can accommodate further functional units (eg photochromic). The mesogenic coat, however, has the specific purpose of providing the self-organising, and ultimately self-assembling, vehicle for the core nano-particles. As noted although shown as spherical, the scaffolds do not necessary have to be spherical. Furthermore, they can be designed to have holes and cavities within their structures, thereby allowing formation of ion channels and binding sites
Organisations
- University of York (Lead Research Organisation)
- National Center for Scientific Research (Centre National de la Recherche Scientifique CNRS) (Collaboration)
- National Institute of Applied Sciences of Lyon (Collaboration)
- University of Neuchâtel (Collaboration)
- University of Paderborn (Collaboration)
- University of Zaragoza (Collaboration)
- University of Warsaw (Collaboration)
Publications
Belaissaoui A
(2010)
Core chirality based tailoring of the liquid crystalline properties of supermolecular tetrapedes
in Soft Matter
Belaissaoui A
(2012)
Supermolecular chiral mesogenic tripedes.
in Chemistry (Weinheim an der Bergstrasse, Germany)
Belaissaoui A
(2013)
Chirally Homogeneous and Heterogeneous Dendritic Liquid Crystals
in Macromolecules
Buluy O
(2012)
Influence of Surface Treatment of Ferromagnetic Nanoparticles on Properties of Thermotropic Nematic Liquid Crystals
in Molecular Crystals and Liquid Crystals
Campidelli S
(2010)
Diastereoisomerically pure fulleropyrrolidines as chiral platforms for the design of optically active liquid crystals.
in Journal of the American Chemical Society
De Oca HM
(2010)
Liquid-crystalline aromatic-aliphatic copolyester bioresorbable polymers.
in Biomaterials
Draper M
(2011)
Self-Assembly and Shape Morphology of Liquid Crystalline Gold Metamaterials
in Advanced Functional Materials
Goodby
(2015)
What makes a liquid crystal? The effect of free volume on soft matter
in Liquid Crystals
Goodby
(2015)
What makes a liquid crystal? The effect of free volume on soft matter
in Liquid Crystals
Goodby J
(2009)
Molecular complexity and the control of self-organising processes
in Liquid Crystals
| Description | A vast number of research results were obtained via the rational design of supramolecular, supermolecular, dendritic and nanoparticulate materials. This work demonstrated the self-organisation and self-assembly of giant molecules via molecular deformation. We have also found new branches of colloidal liquid crystals that do not undergo aggregation and possess metamaterial and magnetic properties. |
| Exploitation Route | The novel design concepts are now being used extensively in other universities across the world, as seen in citation counts. In particular, our work on coated nanoparticles as metamaterials has been viewed as being promising. We have also been developing the materials produced for applications in security devices. A spin off has also been in the area of utilizing biological particles such as the exine shells of plant spores as vehicles and protection devices for various materials such as dyes. We have been in discussions with various companies about potential applications. |
| Sectors | Aerospace, Defence and Marine,Chemicals,Electronics,Other |
| Description | Our work developed into looking at metamaterials based coated nano particles made of metals and magnets. We found that the magnetic particles coated with liquid crystals remained in a colloidal state over at least 3 years without aggregation, and that the particles lowered the switching fields in liquid crystal displays. Conversely gold coated metamaterials exhibited unusually negative dielectric properties. The paper resulting from this work has over 70 citations without self citations. |
| Sector | Aerospace, Defence and Marine,Chemicals,Electronics |
| Impact Types | Economic |
| Description | CSIC |
| Amount | £2,160 (GBP) |
| Funding ID | Grant body: AGAUR-Generalitat de Catalunya |
| Organisation | Spanish National Research Council (CSIC) |
| Sector | Public |
| Country | Spain |
| Start | 07/2006 |
| End | 08/2006 |
| Description | CNRS France |
| Organisation | National Center for Scientific Research (Centre National de la Recherche Scientifique CNRS) |
| Department | The Institute of Physics and Chemistry of Materials of Strasbourg (IPCMS) |
| Country | France |
| Sector | Academic/University |
| PI Contribution | Project Leader: Professor John Goodby, Department of Chemistry, University of York, United Kingdom The Group had extensive experience in all aspects of the synthesis of liquid crystals, from low molar mass to polymeric liquid crystals, from organic to inorganic liquid crystals, and in the up-scaling of synthetic processes. The group also had extensive experience in the characterization of liquid crystals and polymers, including microscopy (POM), thermal analysis (DSC), electrical field studies, refractometry, mechanical analysis (DMA) and X-ray diffraction. The Team's contribution to LC-NANOP was in the areas of synthesis, characterization, theory and computer simulations. After synthesis and initial characterization the best lead materials were made available to the teams at Paderborn, Warsaw and Strasbourg. |
| Collaborator Contribution | Associated Partner: Dr. Daniel Guillon: Institut de Physique et Chimie des Matériaux, Université Louis Pasteur, Strasbourg, France The overall scientific activity of the Strasbourg group dealt with the design, synthesis and characterization of organic materials with specific properties (mesomorphic, nonlinear optical, electroluminescent, magnetic etc). In particular, a large part of their activity concerned low-molecular weight and macromolecular liquid-crystalline materials. The Group had also a considerable and internationally recognised experience in the determination of mesomorphic structures, thanks mainly to well-suited, small-angle X-ray equipment, and to computerised molecular simulations. This expertise was used to establish structure-property relationships in many mesomorphic systems and more generally in self-organised systems. |
| Impact | Details of Innovations of LC-NANOP: LC-NANOP has been involved with developing a new approach to the self-organisation and self-assembly of organic, inorganic and metal nano-particles (NPs) using the unique self-organisation properties of liquid crystals (LCs) to propagate order over large length scales. Thus LC-NANOP has been concerned with the synthesis, characterisation and properties of super- and supra-molecular systems which are formed by deploying a nano-particle as a central scaffold and surrounding it with a coat of liquid crystal. The incorporation of nano-particles into LC systems is a particularly hot topic in the field at the moment, and therefore the work of LC-NANOP is highly relevant. The Highlights of LC-NANOP are as follows: • Self-organising metal nano-particles - The synthesis and structural characterization of a variety of metal (Au, Co, Pt) and metal oxide NPs coated with LCs was achieved. In particular, the ability of gold NPs grafted with soft, adaptive organic layer made of thiol molecules to form spontaneously long range positionally ordered structures was demonstrated. Depending on the molecular structure of thiols: lamellar, columnar or cubic phases were observed. These structures, seemingly non-compatible with the spherical shape of NPs were obtained thanks to the self-segregation of mesogenic and simple n-alkyl ligands at the nanoparticle surfaces. • Self-organising metamaterials - LC coated gold NPs were found to self-organise and to exhibit surface plasmon effects that were wavelength dependent with respect to the nature of the LC coating. • Ferromagnetic self-organising nanoparticles - Mesomorphic dendronized nanoparticles exhibiting room temperature ferromagnetism and Mn clusters have been created and their properties investigated. In addition, magnetic (Co) and non-magnetic (Pt) nanoparticles were functionalized by variety of mesogenic molecules. • Chiral Nano-particles - Chiral nano-particles based on sugar scaffolds with LC coatings were prepared and the transmission of the chirality from the interior to the exterior of the particles was investigated. These nano-particles were found to induce iridescence in nematic LCs. • Dendritic liquid crystals of bent-core mesogens - The first examples of complex mesogenic structures formed by bent-core mesogens attached to dendrimeric dendritic scaffolds were created. These were predicted to exhibit unusual ferroelectric behaviour. • Microphase segregated nano-particles - The first examples of Janus dendritic LCs were created where one face of the supermolecules were composed of disc-like LCs, whereas the other face was composed of rod-like liquid crystals. These systems microphase segregated. • Functional supermolecules - Supermolecular systems were created based on a central scaffold with mesogenic groups attached to the scaffold to provide self-organisation, and in addition a functional unit was also incorporated into the structure. The mesogenic groups included cyanobiphenyls, whereas the functional groups included fullerenes, fluorenes, perylenes, porphyrins etc (ie fluorescent and semi-conducting units). • Polarised Light Emission from OLEDs - The benefit of ordering monodisperse liquid crystal oligomers for linearly polarised emission of light from OLEDs was demonstrated. • Tunable light sources - Tunable light sources have been developed, which have been fabricated by embedding semiconductor microresonators that contain luminescent quantum dots in LCs. In these systems, controlled shifts of the resonance frequency of whispering gallery modes have been demonstrated. • Liquid Crystalline Photovoltaics - A cross network collaboration yielded liquid-crystalline dendrimers that were suitable in improving the morphology of semiconducting composites for organic photovoltaics and semi-conductors (Jpn. J. Appl. Phys. 49, 01AF01, 2010). • Replacement for Transparent ITO Electrodes - An Inter-CRP-collaboration with the SUPRAMATES CRP (Prof. Müllen, Mainz, Germany), succeeded in developing novel transparent graphene electrodes for LC addressing. These could be used to replace indium-tin-oxide, ITO. • Photorefractive effects in complex systems - Investigations of the photorefractive effect in polymer-dispersed liquid crystal (PDLC) indicate that the efficiency of the photorefractive effect (optical gain) can be enhanced by doping of the polymer matrix. Although small molecules were used as dopants, similar effects can be expected to appear by doping with nanoparticles. • Microscopic imaging of liquid crystalline order - A preparation technique was developed that allows microscopic imaging of LC director fields in complex geometries, and in particular in the vicinity of micro- and nanoparticles by means of Fluorescence Confocal Polarising Microscopy. Non-standard case of electroconvection: LC systems with unique electrooptic properties were developed. In particular, a system showing modified anchoring and thus a complete reversal of the electrooptic switching from bright (field-off)/dark (field-on) to dark(field-off)/bright (field-on). CRP research gave evidence that this behavior is due to non-standard electroconvection. Details of the collaborations:: Skills set: Collaborative research necessitates that the partners possess complementary skills sets. LC-NANOP is fortunate to possess experts that are focused on the synthesis of compounds (York, Warsaw, Strasbourg, Zaragoza, Neuchâtel), the characterization of materials (Paderborn, Warsaw, Strasbourg, Zaragoza), the evaluation of physical properties of materials (Paderborn, Warsaw, Strasbourg, Zaragoza), and the simulation (York) of soft-matter systems. Tools set: Collaborative research also requires both complementary tools and specific tools for the selected research. Synthetic capabilities and scale up were provided by York, Warsaw, Strasbourg, Zaragoza, Neuchâtel, characterization techniques involved AFM, polarized near-field optical microscopy, fluorescence confocal polarized microscopy, etc by Paderborn, structural studies involving powder XRD, SAXS, X-ray reflectometry by Warsaw, Strasbourg and Zaragoza, and device engineering of materials was provided by Paderborn. Underpinning the experimental work was modeling and simulation at York. Exchanges: Exchanges were made between the various groups within the CRP, between CRPs, through international visitors from outside of the SONS 2 programme, and through involving research students funded by national programmes. These are exemplied by the following: (i) research in the CRP - Chiral and electroluminescent LCs as well as nanoparticles that were developed in York (IP1) and additives for photovoltaic composites synthesized in Neuchatel (AP3) were studied in Paderborn (IP3). The results were jointly published in scientific journals, oral conference contributions and posters; (ii) a joint publication from the CRP - J Wolska et al, Mesomorphism of branched dimers, Macromolecules, 42, 6375, 2009; (iii) interactions between CRPs - a four week visit by M. Wojcik (Warsaw) to Halle of the SCALES CRP; (iv) international interactions - a visit of two months took place between York and McGill, Canada which involved a visit by a PhD student, J. Millett, and (v) the inclusion of students from national programmes is demonstrated by EPSRC PhD student M. Draper whose delivered a thesis entitled: Golden Liquid Crystal Nanoparticles, research that was supported by Strasbourg. Multidisciplinary: Overall: Progress in the fields of nano-composites and molecular electronics would not have been possible without multidisciplinary collaborations between organic chemists (synthesis), physical chemists (material characterization) and physicists (physical studies of novel effects). • Experimental Science: The CRP was fortunate to have some of the best synthesisers of soft-, self-organising materials and structural and physical property investigators drawn from the EU science base. Multidisciplinary science therefore was a must for the CRP to succeed. Thus, the interactions between the individual projects which were specialised in different fields of synthetic chemistry, analytical and physical chemistry, physics and chemical engineering provided an excellent platform for the development of multidisciplinary research. The methodologies ranged from synthesis to sophisticated analytical tools, to application-oriented characterization of the electric, magnetic, optoelectronic and photonic properties, and the simulations of the mesophases obtained. The results were found to be of interest to other research areas such as organic-based photovoltaics. The direct feedback between the synthesis, the characteristics of the materials applications, their performance and their simulation ensured that all branches of the project benefited from multidisciplinarity. • Theoretical and simulation science: Theoretical and simulation data about structures and dynamics at the molecular level were used to feed the synthesis/characterization activities. The modelling ensured that appropriate synthetic modifications were made as suggested through the simulation results, and at the same time the interpretation of the available structural parameters were taken into consideration for further models. European Added Value: • International: The field of nano-composites is facing strong, world-wide competition, the results of which will have a considerable influence on the economic wealth of the respective countries involved. Through the achievements obtained and those to be expected by the SONS program, European scientists are enabled to share their interdisciplinary experience which is a necessary condition for scientific progress and visibility in this field of increasing importance. • National Programmes and Timeliness: For a number of EU States, there are many concerns about the very nature of nanotechnology, ie what is it?, and the timeliness of its development. In some States nanotechnology is being driven forward with a disregard for the fundamental understanding of the basic concepts associated nano-science. In some EU States national nano-science programmes are lagging behind those being developed by other States or countries worldwide. The added value in the case of LC-NANOP has been to provide a focus for EU scientists to sample many different supermolecular and supramolecular concepts/designs in a collaborative way. This has resulted in this CRP being very fluid and capable of investigating many novel and innovative ideas where those ideas can be evaluated and the results disseminated via the partners for critique and further development. • Scope and Expertise: In terms of expertise and scope, an essential condition for the development of the collaborative interdisciplinary work of this CRP is through such a European-wide collaboration. Thus, it is very important to recognise that the expertise available throughout Europe is an irreplaceable element to the success of this CRP and allows us to be competitive with the USA and the Far East. • Scientific Exchange: Thanks to ESF coordinated funding, the CRP has significantly enhanced the mutual scientific exchange within Europe. The final reports and Mid-term review were sent to EPSRC on 26th October 2010. It should be noted that 35 Papers, 6 Theses, 2 Chapters in Books, and 10 Invited/Plenary Lectures were generated by LC-NANOP. |
| Start Year | 2007 |
| Description | Liquid Crystalline Glycolipids |
| Organisation | National Institute of Applied Sciences of Lyon |
| Country | France |
| Sector | Academic/University |
| PI Contribution | Analysis of the liquid crystalline and self-organizing properties of biologically related glycolipids |
| Collaborator Contribution | Synthesis of novel materials of high purity for analysis |
| Impact | 2 Book Chapters, 8 publications, award of Honorary Doctorate to Goodby |
| Start Year | 2006 |
| Description | Neuchatel University |
| Organisation | University of Neuchatel |
| Country | Switzerland |
| Sector | Academic/University |
| PI Contribution | Project Leader: Professor John Goodby Department of Chemistry, University of York, United Kingdom The Group had extensive experience in all aspects of the synthesis of liquid crystals, from low molar mass to polymeric liquid crystals, from organic to inorganic liquid crystals, and in the up-scaling of synthetic processes. The group also had extensive experience in the characterization of liquid crystals and polymers, including microscopy (POM), thermal analysis (DSC), electrical field studies, refractometry, mechanical analysis (DMA) and X-ray diffraction. The Team's contribution to LC-NANOP was in the areas of synthesis, characterization, theory and computer simulations. After synthesis and initial characterization the best lead materials were made available to the teams at Paderborn, Warsaw and Strasbourg. |
| Collaborator Contribution | Co-operating Partner: Professor Robert Deschenaux, Université de Neuchâtel, Neuchâtel, Switzerland The Neuchâtel Group had extensive experience in all aspects of the synthesis of low and high molar mass liquid crystals, both organic and metallo-organic, and also in the characterization of these materials by techniques, such as optical microscopy and thermal analysis. The Group utilised these techniques in the LC-NANOP project, and contributed to the project primarily through materials developments with York and Strasbourg. |
| Impact | Details of Innovations of LC-NANOP: LC-NANOP has been involved with developing a new approach to the self-organisation and self-assembly of organic, inorganic and metal nano-particles (NPs) using the unique self-organisation properties of liquid crystals (LCs) to propagate order over large length scales. Thus LC-NANOP has been concerned with the synthesis, characterisation and properties of super- and supra-molecular systems which are formed by deploying a nano-particle as a central scaffold and surrounding it with a coat of liquid crystal. The incorporation of nano-particles into LC systems is a particularly hot topic in the field at the moment, and therefore the work of LC-NANOP is highly relevant. The Highlights of LC-NANOP are as follows: • Self-organising metal nano-particles - The synthesis and structural characterization of a variety of metal (Au, Co, Pt) and metal oxide NPs coated with LCs was achieved. In particular, the ability of gold NPs grafted with soft, adaptive organic layer made of thiol molecules to form spontaneously long range positionally ordered structures was demonstrated. Depending on the molecular structure of thiols: lamellar, columnar or cubic phases were observed. These structures, seemingly non-compatible with the spherical shape of NPs were obtained thanks to the self-segregation of mesogenic and simple n-alkyl ligands at the nanoparticle surfaces. • Self-organising metamaterials - LC coated gold NPs were found to self-organise and to exhibit surface plasmon effects that were wavelength dependent with respect to the nature of the LC coating. • Ferromagnetic self-organising nanoparticles - Mesomorphic dendronized nanoparticles exhibiting room temperature ferromagnetism and Mn clusters have been created and their properties investigated. In addition, magnetic (Co) and non-magnetic (Pt) nanoparticles were functionalized by variety of mesogenic molecules. • Chiral Nano-particles - Chiral nano-particles based on sugar scaffolds with LC coatings were prepared and the transmission of the chirality from the interior to the exterior of the particles was investigated. These nano-particles were found to induce iridescence in nematic LCs. • Dendritic liquid crystals of bent-core mesogens - The first examples of complex mesogenic structures formed by bent-core mesogens attached to dendrimeric dendritic scaffolds were created. These were predicted to exhibit unusual ferroelectric behaviour. • Microphase segregated nano-particles - The first examples of Janus dendritic LCs were created where one face of the supermolecules were composed of disc-like LCs, whereas the other face was composed of rod-like liquid crystals. These systems microphase segregated. • Functional supermolecules - Supermolecular systems were created based on a central scaffold with mesogenic groups attached to the scaffold to provide self-organisation, and in addition a functional unit was also incorporated into the structure. The mesogenic groups included cyanobiphenyls, whereas the functional groups included fullerenes, fluorenes, perylenes, porphyrins etc (ie fluorescent and semi-conducting units). • Polarised Light Emission from OLEDs - The benefit of ordering monodisperse liquid crystal oligomers for linearly polarised emission of light from OLEDs was demonstrated. • Tunable light sources - Tunable light sources have been developed, which have been fabricated by embedding semiconductor microresonators that contain luminescent quantum dots in LCs. In these systems, controlled shifts of the resonance frequency of whispering gallery modes have been demonstrated. • Liquid Crystalline Photovoltaics - A cross network collaboration yielded liquid-crystalline dendrimers that were suitable in improving the morphology of semiconducting composites for organic photovoltaics and semi-conductors (Jpn. J. Appl. Phys. 49, 01AF01, 2010). • Replacement for Transparent ITO Electrodes - An Inter-CRP-collaboration with the SUPRAMATES CRP (Prof. Müllen, Mainz, Germany), succeeded in developing novel transparent graphene electrodes for LC addressing. These could be used to replace indium-tin-oxide, ITO. • Photorefractive effects in complex systems - Investigations of the photorefractive effect in polymer-dispersed liquid crystal (PDLC) indicate that the efficiency of the photorefractive effect (optical gain) can be enhanced by doping of the polymer matrix. Although small molecules were used as dopants, similar effects can be expected to appear by doping with nanoparticles. • Microscopic imaging of liquid crystalline order - A preparation technique was developed that allows microscopic imaging of LC director fields in complex geometries, and in particular in the vicinity of micro- and nanoparticles by means of Fluorescence Confocal Polarising Microscopy. Non-standard case of electroconvection: LC systems with unique electrooptic properties were developed. In particular, a system showing modified anchoring and thus a complete reversal of the electrooptic switching from bright (field-off)/dark (field-on) to dark(field-off)/bright (field-on). CRP research gave evidence that this behavior is due to non-standard electroconvection. Details of the collaborations:: Skills set: Collaborative research necessitates that the partners possess complementary skills sets. LC-NANOP is fortunate to possess experts that are focused on the synthesis of compounds (York, Warsaw, Strasbourg, Zaragoza, Neuchâtel), the characterization of materials (Paderborn, Warsaw, Strasbourg, Zaragoza), the evaluation of physical properties of materials (Paderborn, Warsaw, Strasbourg, Zaragoza), and the simulation (York) of soft-matter systems. Tools set: Collaborative research also requires both complementary tools and specific tools for the selected research. Synthetic capabilities and scale up were provided by York, Warsaw, Strasbourg, Zaragoza, Neuchâtel, characterization techniques involved AFM, polarized near-field optical microscopy, fluorescence confocal polarized microscopy, etc by Paderborn, structural studies involving powder XRD, SAXS, X-ray reflectometry by Warsaw, Strasbourg and Zaragoza, and device engineering of materials was provided by Paderborn. Underpinning the experimental work was modeling and simulation at York. Exchanges: Exchanges were made between the various groups within the CRP, between CRPs, through international visitors from outside of the SONS 2 programme, and through involving research students funded by national programmes. These are exemplied by the following: (i) research in the CRP - Chiral and electroluminescent LCs as well as nanoparticles that were developed in York (IP1) and additives for photovoltaic composites synthesized in Neuchatel (AP3) were studied in Paderborn (IP3). The results were jointly published in scientific journals, oral conference contributions and posters; (ii) a joint publication from the CRP - J Wolska et al, Mesomorphism of branched dimers, Macromolecules, 42, 6375, 2009; (iii) interactions between CRPs - a four week visit by M. Wojcik (Warsaw) to Halle of the SCALES CRP; (iv) international interactions - a visit of two months took place between York and McGill, Canada which involved a visit by a PhD student, J. Millett, and (v) the inclusion of students from national programmes is demonstrated by EPSRC PhD student M. Draper whose delivered a thesis entitled: Golden Liquid Crystal Nanoparticles, research that was supported by Strasbourg. Multidisciplinary: Overall: Progress in the fields of nano-composites and molecular electronics would not have been possible without multidisciplinary collaborations between organic chemists (synthesis), physical chemists (material characterization) and physicists (physical studies of novel effects). • Experimental Science: The CRP was fortunate to have some of the best synthesisers of soft-, self-organising materials and structural and physical property investigators drawn from the EU science base. Multidisciplinary science therefore was a must for the CRP to succeed. Thus, the interactions between the individual projects which were specialised in different fields of synthetic chemistry, analytical and physical chemistry, physics and chemical engineering provided an excellent platform for the development of multidisciplinary research. The methodologies ranged from synthesis to sophisticated analytical tools, to application-oriented characterization of the electric, magnetic, optoelectronic and photonic properties, and the simulations of the mesophases obtained. The results were found to be of interest to other research areas such as organic-based photovoltaics. The direct feedback between the synthesis, the characteristics of the materials applications, their performance and their simulation ensured that all branches of the project benefited from multidisciplinarity. • Theoretical and simulation science: Theoretical and simulation data about structures and dynamics at the molecular level were used to feed the synthesis/characterization activities. The modelling ensured that appropriate synthetic modifications were made as suggested through the simulation results, and at the same time the interpretation of the available structural parameters were taken into consideration for further models. European Added Value: • International: The field of nano-composites is facing strong, world-wide competition, the results of which will have a considerable influence on the economic wealth of the respective countries involved. Through the achievements obtained and those to be expected by the SONS program, European scientists are enabled to share their interdisciplinary experience which is a necessary condition for scientific progress and visibility in this field of increasing importance. • National Programmes and Timeliness: For a number of EU States, there are many concerns about the very nature of nanotechnology, ie what is it?, and the timeliness of its development. In some States nanotechnology is being driven forward with a disregard for the fundamental understanding of the basic concepts associated nano-science. In some EU States national nano-science programmes are lagging behind those being developed by other States or countries worldwide. The added value in the case of LC-NANOP has been to provide a focus for EU scientists to sample many different supermolecular and supramolecular concepts/designs in a collaborative way. This has resulted in this CRP being very fluid and capable of investigating many novel and innovative ideas where those ideas can be evaluated and the results disseminated via the partners for critique and further development. • Scope and Expertise: In terms of expertise and scope, an essential condition for the development of the collaborative interdisciplinary work of this CRP is through such a European-wide collaboration. Thus, it is very important to recognise that the expertise available throughout Europe is an irreplaceable element to the success of this CRP and allows us to be competitive with the USA and the Far East. • Scientific Exchange: Thanks to ESF coordinated funding, the CRP has significantly enhanced the mutual scientific exchange within Europe. The final reports and Mid-term review were sent to EPSRC on 26th October 2010. It should be noted that 35 Papers, 6 Theses, 2 Chapters in Books, and 10 Invited/Plenary Lectures were generated by LC-NANOP. |
| Start Year | 2006 |
| Description | University of Paderborn |
| Organisation | University of Paderborn |
| Country | Germany |
| Sector | Academic/University |
| PI Contribution | Project Leader: Professor John Goodby, Department of Chemistry, University of York, United Kingdom The Group had extensive experience in all aspects of the synthesis of liquid crystals, from low molar mass to polymeric liquid crystals, from organic to inorganic liquid crystals, and in the up-scaling of synthetic processes. The group also had extensive experience in the characterization of liquid crystals and polymers, including microscopy (POM), thermal analysis (DSC), electrical field studies, refractometry, mechanical analysis (DMA) and X-ray diffraction. The Team's contribution to LC-NANOP was in the areas of synthesis, characterization, theory and computer simulations. After synthesis and initial characterization the best lead materials were made available to the teams at Paderborn, Warsaw and Strasbourg. |
| Collaborator Contribution | Principal Investigator: Professor Heinz Kitzerow, Faculty of Science, University of Paderborn, Paderborn, Germany The Liquid Crystal Group in Paderborn was involved with the physical chemistry of LCs, and was specialised in investigating the structure and the electrooptic, optoelectronic and photonic properties of complex systems, including micro- and nano-structures such as LC/polymer composites, organic light emitting devices and photonic crystals. |
| Impact | Details of Innovations of LC-NANOP: LC-NANOP has been involved with developing a new approach to the self-organisation and self-assembly of organic, inorganic and metal nano-particles (NPs) using the unique self-organisation properties of liquid crystals (LCs) to propagate order over large length scales. Thus LC-NANOP has been concerned with the synthesis, characterisation and properties of super- and supra-molecular systems which are formed by deploying a nano-particle as a central scaffold and surrounding it with a coat of liquid crystal. The incorporation of nano-particles into LC systems is a particularly hot topic in the field at the moment, and therefore the work of LC-NANOP is highly relevant. The Highlights of LC-NANOP are as follows: • Self-organising metal nano-particles - The synthesis and structural characterization of a variety of metal (Au, Co, Pt) and metal oxide NPs coated with LCs was achieved. In particular, the ability of gold NPs grafted with soft, adaptive organic layer made of thiol molecules to form spontaneously long range positionally ordered structures was demonstrated. Depending on the molecular structure of thiols: lamellar, columnar or cubic phases were observed. These structures, seemingly non-compatible with the spherical shape of NPs were obtained thanks to the self-segregation of mesogenic and simple n-alkyl ligands at the nanoparticle surfaces. • Self-organising metamaterials - LC coated gold NPs were found to self-organise and to exhibit surface plasmon effects that were wavelength dependent with respect to the nature of the LC coating. • Ferromagnetic self-organising nanoparticles - Mesomorphic dendronized nanoparticles exhibiting room temperature ferromagnetism and Mn clusters have been created and their properties investigated. In addition, magnetic (Co) and non-magnetic (Pt) nanoparticles were functionalized by variety of mesogenic molecules. • Chiral Nano-particles - Chiral nano-particles based on sugar scaffolds with LC coatings were prepared and the transmission of the chirality from the interior to the exterior of the particles was investigated. These nano-particles were found to induce iridescence in nematic LCs. • Dendritic liquid crystals of bent-core mesogens - The first examples of complex mesogenic structures formed by bent-core mesogens attached to dendrimeric dendritic scaffolds were created. These were predicted to exhibit unusual ferroelectric behaviour. • Microphase segregated nano-particles - The first examples of Janus dendritic LCs were created where one face of the supermolecules were composed of disc-like LCs, whereas the other face was composed of rod-like liquid crystals. These systems microphase segregated. • Functional supermolecules - Supermolecular systems were created based on a central scaffold with mesogenic groups attached to the scaffold to provide self-organisation, and in addition a functional unit was also incorporated into the structure. The mesogenic groups included cyanobiphenyls, whereas the functional groups included fullerenes, fluorenes, perylenes, porphyrins etc (ie fluorescent and semi-conducting units). • Polarised Light Emission from OLEDs - The benefit of ordering monodisperse liquid crystal oligomers for linearly polarised emission of light from OLEDs was demonstrated. • Tunable light sources - Tunable light sources have been developed, which have been fabricated by embedding semiconductor microresonators that contain luminescent quantum dots in LCs. In these systems, controlled shifts of the resonance frequency of whispering gallery modes have been demonstrated. • Liquid Crystalline Photovoltaics - A cross network collaboration yielded liquid-crystalline dendrimers that were suitable in improving the morphology of semiconducting composites for organic photovoltaics and semi-conductors (Jpn. J. Appl. Phys. 49, 01AF01, 2010). • Replacement for Transparent ITO Electrodes - An Inter-CRP-collaboration with the SUPRAMATES CRP (Prof. Müllen, Mainz, Germany), succeeded in developing novel transparent graphene electrodes for LC addressing. These could be used to replace indium-tin-oxide, ITO. • Photorefractive effects in complex systems - Investigations of the photorefractive effect in polymer-dispersed liquid crystal (PDLC) indicate that the efficiency of the photorefractive effect (optical gain) can be enhanced by doping of the polymer matrix. Although small molecules were used as dopants, similar effects can be expected to appear by doping with nanoparticles. • Microscopic imaging of liquid crystalline order - A preparation technique was developed that allows microscopic imaging of LC director fields in complex geometries, and in particular in the vicinity of micro- and nanoparticles by means of Fluorescence Confocal Polarising Microscopy. Non-standard case of electroconvection: LC systems with unique electrooptic properties were developed. In particular, a system showing modified anchoring and thus a complete reversal of the electrooptic switching from bright (field-off)/dark (field-on) to dark(field-off)/bright (field-on). CRP research gave evidence that this behavior is due to non-standard electroconvection. Details of the collaborations:: Skills set: Collaborative research necessitates that the partners possess complementary skills sets. LC-NANOP is fortunate to possess experts that are focused on the synthesis of compounds (York, Warsaw, Strasbourg, Zaragoza, Neuchâtel), the characterization of materials (Paderborn, Warsaw, Strasbourg, Zaragoza), the evaluation of physical properties of materials (Paderborn, Warsaw, Strasbourg, Zaragoza), and the simulation (York) of soft-matter systems. Tools set: Collaborative research also requires both complementary tools and specific tools for the selected research. Synthetic capabilities and scale up were provided by York, Warsaw, Strasbourg, Zaragoza, Neuchâtel, characterization techniques involved AFM, polarized near-field optical microscopy, fluorescence confocal polarized microscopy, etc by Paderborn, structural studies involving powder XRD, SAXS, X-ray reflectometry by Warsaw, Strasbourg and Zaragoza, and device engineering of materials was provided by Paderborn. Underpinning the experimental work was modeling and simulation at York. Exchanges: Exchanges were made between the various groups within the CRP, between CRPs, through international visitors from outside of the SONS 2 programme, and through involving research students funded by national programmes. These are exemplied by the following: (i) research in the CRP - Chiral and electroluminescent LCs as well as nanoparticles that were developed in York (IP1) and additives for photovoltaic composites synthesized in Neuchatel (AP3) were studied in Paderborn (IP3). The results were jointly published in scientific journals, oral conference contributions and posters; (ii) a joint publication from the CRP - J Wolska et al, Mesomorphism of branched dimers, Macromolecules, 42, 6375, 2009; (iii) interactions between CRPs - a four week visit by M. Wojcik (Warsaw) to Halle of the SCALES CRP; (iv) international interactions - a visit of two months took place between York and McGill, Canada which involved a visit by a PhD student, J. Millett, and (v) the inclusion of students from national programmes is demonstrated by EPSRC PhD student M. Draper whose delivered a thesis entitled: Golden Liquid Crystal Nanoparticles, research that was supported by Strasbourg. Multidisciplinary: Overall: Progress in the fields of nano-composites and molecular electronics would not have been possible without multidisciplinary collaborations between organic chemists (synthesis), physical chemists (material characterization) and physicists (physical studies of novel effects). • Experimental Science: The CRP was fortunate to have some of the best synthesisers of soft-, self-organising materials and structural and physical property investigators drawn from the EU science base. Multidisciplinary science therefore was a must for the CRP to succeed. Thus, the interactions between the individual projects which were specialised in different fields of synthetic chemistry, analytical and physical chemistry, physics and chemical engineering provided an excellent platform for the development of multidisciplinary research. The methodologies ranged from synthesis to sophisticated analytical tools, to application-oriented characterization of the electric, magnetic, optoelectronic and photonic properties, and the simulations of the mesophases obtained. The results were found to be of interest to other research areas such as organic-based photovoltaics. The direct feedback between the synthesis, the characteristics of the materials applications, their performance and their simulation ensured that all branches of the project benefited from multidisciplinarity. • Theoretical and simulation science: Theoretical and simulation data about structures and dynamics at the molecular level were used to feed the synthesis/characterization activities. The modelling ensured that appropriate synthetic modifications were made as suggested through the simulation results, and at the same time the interpretation of the available structural parameters were taken into consideration for further models. European Added Value: • International: The field of nano-composites is facing strong, world-wide competition, the results of which will have a considerable influence on the economic wealth of the respective countries involved. Through the achievements obtained and those to be expected by the SONS program, European scientists are enabled to share their interdisciplinary experience which is a necessary condition for scientific progress and visibility in this field of increasing importance. • National Programmes and Timeliness: For a number of EU States, there are many concerns about the very nature of nanotechnology, ie what is it?, and the timeliness of its development. In some States nanotechnology is being driven forward with a disregard for the fundamental understanding of the basic concepts associated nano-science. In some EU States national nano-science programmes are lagging behind those being developed by other States or countries worldwide. The added value in the case of LC-NANOP has been to provide a focus for EU scientists to sample many different supermolecular and supramolecular concepts/designs in a collaborative way. This has resulted in this CRP being very fluid and capable of investigating many novel and innovative ideas where those ideas can be evaluated and the results disseminated via the partners for critique and further development. • Scope and Expertise: In terms of expertise and scope, an essential condition for the development of the collaborative interdisciplinary work of this CRP is through such a European-wide collaboration. Thus, it is very important to recognise that the expertise available throughout Europe is an irreplaceable element to the success of this CRP and allows us to be competitive with the USA and the Far East. • Scientific Exchange: Thanks to ESF coordinated funding, the CRP has significantly enhanced the mutual scientific exchange within Europe. The final reports and Mid-term review were sent to EPSRC on 26th October 2010. It should be noted that 35 Papers, 6 Theses, 2 Chapters in Books, and 10 Invited/Plenary Lectures were generated by LC-NANOP. |
| Start Year | 2007 |
| Description | University of Warsaw |
| Organisation | University of Warsaw |
| Country | Poland |
| Sector | Academic/University |
| PI Contribution | Project Leader: Professor John Goodby, Department of Chemistry, University of York, United Kingdom The Group had extensive experience in all aspects of the synthesis of liquid crystals, from low molar mass to polymeric liquid crystals, from organic to inorganic liquid crystals, and in the up-scaling of synthetic processes. The group also had extensive experience in the characterization of liquid crystals and polymers, including microscopy (POM), thermal analysis (DSC), electrical field studies, refractometry, mechanical analysis (DMA) and X-ray diffraction. The Team's contribution to LC-NANOP was in the areas of synthesis, characterization, theory and computer simulations. After synthesis and initial characterization the best lead materials were made available to the teams at Paderborn, Warsaw and Strasbourg. |
| Collaborator Contribution | Principal Investigators: Professor Ewa Gorecka, Faculty of Science, University of Warsaw, Warsaw, Poland The Group's research was focused on electrical and optical properties of LCs. The group the characterization of crystal structures and molecular dynamics using electron spin resonance methods (ESR). Sophisticated set-ups for measuring birefringence, optical rotatory power, conoscopy, electro-optic response had been built. A picoseconds laser for studies of nonlinear optical (NLO) properties was also available. |
| Impact | Details of Innovations of LC-NANOP: LC-NANOP has been involved with developing a new approach to the self-organisation and self-assembly of organic, inorganic and metal nano-particles (NPs) using the unique self-organisation properties of liquid crystals (LCs) to propagate order over large length scales. Thus LC-NANOP has been concerned with the synthesis, characterisation and properties of super- and supra-molecular systems which are formed by deploying a nano-particle as a central scaffold and surrounding it with a coat of liquid crystal. The incorporation of nano-particles into LC systems is a particularly hot topic in the field at the moment, and therefore the work of LC-NANOP is highly relevant. The Highlights of LC-NANOP are as follows: • Self-organising metal nano-particles - The synthesis and structural characterization of a variety of metal (Au, Co, Pt) and metal oxide NPs coated with LCs was achieved. In particular, the ability of gold NPs grafted with soft, adaptive organic layer made of thiol molecules to form spontaneously long range positionally ordered structures was demonstrated. Depending on the molecular structure of thiols: lamellar, columnar or cubic phases were observed. These structures, seemingly non-compatible with the spherical shape of NPs were obtained thanks to the self-segregation of mesogenic and simple n-alkyl ligands at the nanoparticle surfaces. • Self-organising metamaterials - LC coated gold NPs were found to self-organise and to exhibit surface plasmon effects that were wavelength dependent with respect to the nature of the LC coating. • Ferromagnetic self-organising nanoparticles - Mesomorphic dendronized nanoparticles exhibiting room temperature ferromagnetism and Mn clusters have been created and their properties investigated. In addition, magnetic (Co) and non-magnetic (Pt) nanoparticles were functionalized by variety of mesogenic molecules. • Chiral Nano-particles - Chiral nano-particles based on sugar scaffolds with LC coatings were prepared and the transmission of the chirality from the interior to the exterior of the particles was investigated. These nano-particles were found to induce iridescence in nematic LCs. • Dendritic liquid crystals of bent-core mesogens - The first examples of complex mesogenic structures formed by bent-core mesogens attached to dendrimeric dendritic scaffolds were created. These were predicted to exhibit unusual ferroelectric behaviour. • Microphase segregated nano-particles - The first examples of Janus dendritic LCs were created where one face of the supermolecules were composed of disc-like LCs, whereas the other face was composed of rod-like liquid crystals. These systems microphase segregated. • Functional supermolecules - Supermolecular systems were created based on a central scaffold with mesogenic groups attached to the scaffold to provide self-organisation, and in addition a functional unit was also incorporated into the structure. The mesogenic groups included cyanobiphenyls, whereas the functional groups included fullerenes, fluorenes, perylenes, porphyrins etc (ie fluorescent and semi-conducting units). • Polarised Light Emission from OLEDs - The benefit of ordering monodisperse liquid crystal oligomers for linearly polarised emission of light from OLEDs was demonstrated. • Tunable light sources - Tunable light sources have been developed, which have been fabricated by embedding semiconductor microresonators that contain luminescent quantum dots in LCs. In these systems, controlled shifts of the resonance frequency of whispering gallery modes have been demonstrated. • Liquid Crystalline Photovoltaics - A cross network collaboration yielded liquid-crystalline dendrimers that were suitable in improving the morphology of semiconducting composites for organic photovoltaics and semi-conductors (Jpn. J. Appl. Phys. 49, 01AF01, 2010). • Replacement for Transparent ITO Electrodes - An Inter-CRP-collaboration with the SUPRAMATES CRP (Prof. Müllen, Mainz, Germany), succeeded in developing novel transparent graphene electrodes for LC addressing. These could be used to replace indium-tin-oxide, ITO. • Photorefractive effects in complex systems - Investigations of the photorefractive effect in polymer-dispersed liquid crystal (PDLC) indicate that the efficiency of the photorefractive effect (optical gain) can be enhanced by doping of the polymer matrix. Although small molecules were used as dopants, similar effects can be expected to appear by doping with nanoparticles. • Microscopic imaging of liquid crystalline order - A preparation technique was developed that allows microscopic imaging of LC director fields in complex geometries, and in particular in the vicinity of micro- and nanoparticles by means of Fluorescence Confocal Polarising Microscopy. Non-standard case of electroconvection: LC systems with unique electrooptic properties were developed. In particular, a system showing modified anchoring and thus a complete reversal of the electrooptic switching from bright (field-off)/dark (field-on) to dark(field-off)/bright (field-on). CRP research gave evidence that this behavior is due to non-standard electroconvection. Details of the collaborations:: Skills set: Collaborative research necessitates that the partners possess complementary skills sets. LC-NANOP is fortunate to possess experts that are focused on the synthesis of compounds (York, Warsaw, Strasbourg, Zaragoza, Neuchâtel), the characterization of materials (Paderborn, Warsaw, Strasbourg, Zaragoza), the evaluation of physical properties of materials (Paderborn, Warsaw, Strasbourg, Zaragoza), and the simulation (York) of soft-matter systems. Tools set: Collaborative research also requires both complementary tools and specific tools for the selected research. Synthetic capabilities and scale up were provided by York, Warsaw, Strasbourg, Zaragoza, Neuchâtel, characterization techniques involved AFM, polarized near-field optical microscopy, fluorescence confocal polarized microscopy, etc by Paderborn, structural studies involving powder XRD, SAXS, X-ray reflectometry by Warsaw, Strasbourg and Zaragoza, and device engineering of materials was provided by Paderborn. Underpinning the experimental work was modeling and simulation at York. Exchanges: Exchanges were made between the various groups within the CRP, between CRPs, through international visitors from outside of the SONS 2 programme, and through involving research students funded by national programmes. These are exemplied by the following: (i) research in the CRP - Chiral and electroluminescent LCs as well as nanoparticles that were developed in York (IP1) and additives for photovoltaic composites synthesized in Neuchatel (AP3) were studied in Paderborn (IP3). The results were jointly published in scientific journals, oral conference contributions and posters; (ii) a joint publication from the CRP - J Wolska et al, Mesomorphism of branched dimers, Macromolecules, 42, 6375, 2009; (iii) interactions between CRPs - a four week visit by M. Wojcik (Warsaw) to Halle of the SCALES CRP; (iv) international interactions - a visit of two months took place between York and McGill, Canada which involved a visit by a PhD student, J. Millett, and (v) the inclusion of students from national programmes is demonstrated by EPSRC PhD student M. Draper whose delivered a thesis entitled: Golden Liquid Crystal Nanoparticles, research that was supported by Strasbourg. Multidisciplinary: Overall: Progress in the fields of nano-composites and molecular electronics would not have been possible without multidisciplinary collaborations between organic chemists (synthesis), physical chemists (material characterization) and physicists (physical studies of novel effects). • Experimental Science: The CRP was fortunate to have some of the best synthesisers of soft-, self-organising materials and structural and physical property investigators drawn from the EU science base. Multidisciplinary science therefore was a must for the CRP to succeed. Thus, the interactions between the individual projects which were specialised in different fields of synthetic chemistry, analytical and physical chemistry, physics and chemical engineering provided an excellent platform for the development of multidisciplinary research. The methodologies ranged from synthesis to sophisticated analytical tools, to application-oriented characterization of the electric, magnetic, optoelectronic and photonic properties, and the simulations of the mesophases obtained. The results were found to be of interest to other research areas such as organic-based photovoltaics. The direct feedback between the synthesis, the characteristics of the materials applications, their performance and their simulation ensured that all branches of the project benefited from multidisciplinarity. • Theoretical and simulation science: Theoretical and simulation data about structures and dynamics at the molecular level were used to feed the synthesis/characterization activities. The modelling ensured that appropriate synthetic modifications were made as suggested through the simulation results, and at the same time the interpretation of the available structural parameters were taken into consideration for further models. European Added Value: • International: The field of nano-composites is facing strong, world-wide competition, the results of which will have a considerable influence on the economic wealth of the respective countries involved. Through the achievements obtained and those to be expected by the SONS program, European scientists are enabled to share their interdisciplinary experience which is a necessary condition for scientific progress and visibility in this field of increasing importance. • National Programmes and Timeliness: For a number of EU States, there are many concerns about the very nature of nanotechnology, ie what is it?, and the timeliness of its development. In some States nanotechnology is being driven forward with a disregard for the fundamental understanding of the basic concepts associated nano-science. In some EU States national nano-science programmes are lagging behind those being developed by other States or countries worldwide. The added value in the case of LC-NANOP has been to provide a focus for EU scientists to sample many different supermolecular and supramolecular concepts/designs in a collaborative way. This has resulted in this CRP being very fluid and capable of investigating many novel and innovative ideas where those ideas can be evaluated and the results disseminated via the partners for critique and further development. • Scope and Expertise: In terms of expertise and scope, an essential condition for the development of the collaborative interdisciplinary work of this CRP is through such a European-wide collaboration. Thus, it is very important to recognise that the expertise available throughout Europe is an irreplaceable element to the success of this CRP and allows us to be competitive with the USA and the Far East. • Scientific Exchange: Thanks to ESF coordinated funding, the CRP has significantly enhanced the mutual scientific exchange within Europe. The final reports and Mid-term review were sent to EPSRC on 26th October 2010. It should be noted that 35 Papers, 6 Theses, 2 Chapters in Books, and 10 Invited/Plenary Lectures were generated by LC-NANOP. |
| Start Year | 2007 |
| Description | University of Zaragoza |
| Organisation | University of Zaragoza |
| Country | Spain |
| Sector | Academic/University |
| PI Contribution | Project Leader: Professor John Goodby, Department of Chemistry, University of York, United Kingdom The Group had extensive experience in all aspects of the synthesis of liquid crystals, from low molar mass to polymeric liquid crystals, from organic to inorganic liquid crystals, and in the up-scaling of synthetic processes. The group also had extensive experience in the characterization of liquid crystals and polymers, including microscopy (POM), thermal analysis (DSC), electrical field studies, refractometry, mechanical analysis (DMA) and X-ray diffraction. The Team's contribution to LC-NANOP was in the areas of synthesis, characterization, theory and computer simulations. After synthesis and initial characterization the best lead materials were made available to the teams at Paderborn, Warsaw and Strasbourg. |
| Collaborator Contribution | Associated Partner: Professor José Serrano, Facultad de Ciencias, Universidad de Zaragoza, CSIC, Zaragoza, Spain The Zaragoza Group had extensive experience in all aspects of the synthesis of low and high molar mass liquid crystals, both organic and metal-organic, and also in the characterization of these materials by several techniques, such as optical microscopy, thermal analysis, electric and magnetic field studies, circular dichroism, nuclear magnetic resonance and X-ray diffraction. The Group utilised all of these techniques in the LC-NANOP project, and contributed to the project primarily through materials developments with Paderborn, Warsaw and Strasbourg. |
| Impact | Details of Innovations of LC-NANOP: LC-NANOP has been involved with developing a new approach to the self-organisation and self-assembly of organic, inorganic and metal nano-particles (NPs) using the unique self-organisation properties of liquid crystals (LCs) to propagate order over large length scales. Thus LC-NANOP has been concerned with the synthesis, characterisation and properties of super- and supra-molecular systems which are formed by deploying a nano-particle as a central scaffold and surrounding it with a coat of liquid crystal. The incorporation of nano-particles into LC systems is a particularly hot topic in the field at the moment, and therefore the work of LC-NANOP is highly relevant. The Highlights of LC-NANOP are as follows: • Self-organising metal nano-particles - The synthesis and structural characterization of a variety of metal (Au, Co, Pt) and metal oxide NPs coated with LCs was achieved. In particular, the ability of gold NPs grafted with soft, adaptive organic layer made of thiol molecules to form spontaneously long range positionally ordered structures was demonstrated. Depending on the molecular structure of thiols: lamellar, columnar or cubic phases were observed. These structures, seemingly non-compatible with the spherical shape of NPs were obtained thanks to the self-segregation of mesogenic and simple n-alkyl ligands at the nanoparticle surfaces. • Self-organising metamaterials - LC coated gold NPs were found to self-organise and to exhibit surface plasmon effects that were wavelength dependent with respect to the nature of the LC coating. • Ferromagnetic self-organising nanoparticles - Mesomorphic dendronized nanoparticles exhibiting room temperature ferromagnetism and Mn clusters have been created and their properties investigated. In addition, magnetic (Co) and non-magnetic (Pt) nanoparticles were functionalized by variety of mesogenic molecules. • Chiral Nano-particles - Chiral nano-particles based on sugar scaffolds with LC coatings were prepared and the transmission of the chirality from the interior to the exterior of the particles was investigated. These nano-particles were found to induce iridescence in nematic LCs. • Dendritic liquid crystals of bent-core mesogens - The first examples of complex mesogenic structures formed by bent-core mesogens attached to dendrimeric dendritic scaffolds were created. These were predicted to exhibit unusual ferroelectric behaviour. • Microphase segregated nano-particles - The first examples of Janus dendritic LCs were created where one face of the supermolecules were composed of disc-like LCs, whereas the other face was composed of rod-like liquid crystals. These systems microphase segregated. • Functional supermolecules - Supermolecular systems were created based on a central scaffold with mesogenic groups attached to the scaffold to provide self-organisation, and in addition a functional unit was also incorporated into the structure. The mesogenic groups included cyanobiphenyls, whereas the functional groups included fullerenes, fluorenes, perylenes, porphyrins etc (ie fluorescent and semi-conducting units). • Polarised Light Emission from OLEDs - The benefit of ordering monodisperse liquid crystal oligomers for linearly polarised emission of light from OLEDs was demonstrated. • Tunable light sources - Tunable light sources have been developed, which have been fabricated by embedding semiconductor microresonators that contain luminescent quantum dots in LCs. In these systems, controlled shifts of the resonance frequency of whispering gallery modes have been demonstrated. • Liquid Crystalline Photovoltaics - A cross network collaboration yielded liquid-crystalline dendrimers that were suitable in improving the morphology of semiconducting composites for organic photovoltaics and semi-conductors (Jpn. J. Appl. Phys. 49, 01AF01, 2010). • Replacement for Transparent ITO Electrodes - An Inter-CRP-collaboration with the SUPRAMATES CRP (Prof. Müllen, Mainz, Germany), succeeded in developing novel transparent graphene electrodes for LC addressing. These could be used to replace indium-tin-oxide, ITO. • Photorefractive effects in complex systems - Investigations of the photorefractive effect in polymer-dispersed liquid crystal (PDLC) indicate that the efficiency of the photorefractive effect (optical gain) can be enhanced by doping of the polymer matrix. Although small molecules were used as dopants, similar effects can be expected to appear by doping with nanoparticles. • Microscopic imaging of liquid crystalline order - A preparation technique was developed that allows microscopic imaging of LC director fields in complex geometries, and in particular in the vicinity of micro- and nanoparticles by means of Fluorescence Confocal Polarising Microscopy. Non-standard case of electroconvection: LC systems with unique electrooptic properties were developed. In particular, a system showing modified anchoring and thus a complete reversal of the electrooptic switching from bright (field-off)/dark (field-on) to dark(field-off)/bright (field-on). CRP research gave evidence that this behavior is due to non-standard electroconvection. Details of the collaborations:: Skills set: Collaborative research necessitates that the partners possess complementary skills sets. LC-NANOP is fortunate to possess experts that are focused on the synthesis of compounds (York, Warsaw, Strasbourg, Zaragoza, Neuchâtel), the characterization of materials (Paderborn, Warsaw, Strasbourg, Zaragoza), the evaluation of physical properties of materials (Paderborn, Warsaw, Strasbourg, Zaragoza), and the simulation (York) of soft-matter systems. Tools set: Collaborative research also requires both complementary tools and specific tools for the selected research. Synthetic capabilities and scale up were provided by York, Warsaw, Strasbourg, Zaragoza, Neuchâtel, characterization techniques involved AFM, polarized near-field optical microscopy, fluorescence confocal polarized microscopy, etc by Paderborn, structural studies involving powder XRD, SAXS, X-ray reflectometry by Warsaw, Strasbourg and Zaragoza, and device engineering of materials was provided by Paderborn. Underpinning the experimental work was modeling and simulation at York. Exchanges: Exchanges were made between the various groups within the CRP, between CRPs, through international visitors from outside of the SONS 2 programme, and through involving research students funded by national programmes. These are exemplied by the following: (i) research in the CRP - Chiral and electroluminescent LCs as well as nanoparticles that were developed in York (IP1) and additives for photovoltaic composites synthesized in Neuchatel (AP3) were studied in Paderborn (IP3). The results were jointly published in scientific journals, oral conference contributions and posters; (ii) a joint publication from the CRP - J Wolska et al, Mesomorphism of branched dimers, Macromolecules, 42, 6375, 2009; (iii) interactions between CRPs - a four week visit by M. Wojcik (Warsaw) to Halle of the SCALES CRP; (iv) international interactions - a visit of two months took place between York and McGill, Canada which involved a visit by a PhD student, J. Millett, and (v) the inclusion of students from national programmes is demonstrated by EPSRC PhD student M. Draper whose delivered a thesis entitled: Golden Liquid Crystal Nanoparticles, research that was supported by Strasbourg. Multidisciplinary: Overall: Progress in the fields of nano-composites and molecular electronics would not have been possible without multidisciplinary collaborations between organic chemists (synthesis), physical chemists (material characterization) and physicists (physical studies of novel effects). • Experimental Science: The CRP was fortunate to have some of the best synthesisers of soft-, self-organising materials and structural and physical property investigators drawn from the EU science base. Multidisciplinary science therefore was a must for the CRP to succeed. Thus, the interactions between the individual projects which were specialised in different fields of synthetic chemistry, analytical and physical chemistry, physics and chemical engineering provided an excellent platform for the development of multidisciplinary research. The methodologies ranged from synthesis to sophisticated analytical tools, to application-oriented characterization of the electric, magnetic, optoelectronic and photonic properties, and the simulations of the mesophases obtained. The results were found to be of interest to other research areas such as organic-based photovoltaics. The direct feedback between the synthesis, the characteristics of the materials applications, their performance and their simulation ensured that all branches of the project benefited from multidisciplinarity. • Theoretical and simulation science: Theoretical and simulation data about structures and dynamics at the molecular level were used to feed the synthesis/characterization activities. The modelling ensured that appropriate synthetic modifications were made as suggested through the simulation results, and at the same time the interpretation of the available structural parameters were taken into consideration for further models. European Added Value: • International: The field of nano-composites is facing strong, world-wide competition, the results of which will have a considerable influence on the economic wealth of the respective countries involved. Through the achievements obtained and those to be expected by the SONS program, European scientists are enabled to share their interdisciplinary experience which is a necessary condition for scientific progress and visibility in this field of increasing importance. • National Programmes and Timeliness: For a number of EU States, there are many concerns about the very nature of nanotechnology, ie what is it?, and the timeliness of its development. In some States nanotechnology is being driven forward with a disregard for the fundamental understanding of the basic concepts associated nano-science. In some EU States national nano-science programmes are lagging behind those being developed by other States or countries worldwide. The added value in the case of LC-NANOP has been to provide a focus for EU scientists to sample many different supermolecular and supramolecular concepts/designs in a collaborative way. This has resulted in this CRP being very fluid and capable of investigating many novel and innovative ideas where those ideas can be evaluated and the results disseminated via the partners for critique and further development. • Scope and Expertise: In terms of expertise and scope, an essential condition for the development of the collaborative interdisciplinary work of this CRP is through such a European-wide collaboration. Thus, it is very important to recognise that the expertise available throughout Europe is an irreplaceable element to the success of this CRP and allows us to be competitive with the USA and the Far East. • Scientific Exchange: Thanks to ESF coordinated funding, the CRP has significantly enhanced the mutual scientific exchange within Europe. The final reports and Mid-term review were sent to EPSRC on 26th October 2010. It should be noted that 35 Papers, 6 Theses, 2 Chapters in Books, and 10 Invited/Plenary Lectures were generated by LC-NANOP. |
| Start Year | 2007 |