New and Improved Electroceramics
Lead Research Organisation:
University of Sheffield
Department Name: Materials Science and Engineering
Abstract
This Large Grant proposal combines the expertise of Sheffield and Leeds to establish a major electroceramics research hub. Electroceramics are advanced materials whose properties and applications depend on close control of crystal structure, chemical composition, ceramic microstructure, dopants and dopant (or defect) distribution. In most cases, properties depend on a complex interplay of structural, processing and compositional variables. They find applications in various physical forms, eg as ceramic discs, thick and thin films and multi-layer devices consisting of alternating layers (up to several hundred) of ceramic and metal electrodes. The particular property of interest may be a bulk property of the crystals, for example, high levels of ionic conductivity, mixed electronic-ionic conduction, ferro-, pyro- piezo-electricity or ferrimagnetism. Alternatively, it may relate specifically to the grain boundaries (or surface layers) in polycrystalline materials and to small differences in composition and therefore electrical behaviour between the bulk and grain boundary (or surface) regions. Such heterogeneous, or functionally-graded ceramics find many applications eg non-ohmic devices in current limiters such as varistors and thermistors. This proposal focuses on new and improved electroceramics for potential near- and long-term applications. The work will be carried out by a multidisciplinary team with complementary skills in materials discovery, modelling, processing and advanced characterisation. Such a multifaceted approach to electroceramics research and development does not exist in the UK within a single institution and the establishment of a 'hub' between the two universities will allow us to compete with the best in the world. Three work packages are proposed.I. New and improved bulk materials: structure-property relations, including: (a) novel perovskite-type materials with targeted functionality: ferroelectricity, reversible electro-strain, piezoelectricity, magneto-electric coupling and mixed conductivity; (b) development of new low temperature co-fired ceramics based on Sillenites; (c) oxygen nonstoichiometry and core-shell phenomena in doped BaTiO3; (d) development of improved lithium battery cathodes based on layered rock salt structures. II. Materials processing and development in thin and thick film form, including:(a) BiFeO3-PbTiO3 and BiMeO3 thin films for ferroelastic/ferroelectric switching for actuator and memory applications; (b) thin film feasibility studies on Solid Oxide Fuel Cell structures; (c) thick and thin films based on the novel ferroelectric system Ba2RETi2Nb3O15 to assess their potential device applications; (d) development of a masked Electrophoretic Deposition technique to deposit planar magnetoelectric composites based on Pb(Zr,Ti)O3-Pb(Ni,Nb)O3 (soft piezoelectric) and (La,Ca)MnO3 (magnetostrictor). III. Modelling of bulk materials and interfacial phenomena: (a) Development of Finite Element modelling of current pathways in (i) heterogeneous ceramics, (ii) local probe measurements within grains and across individual grain boundaries and (iii) multilayer devices; the results will be used to simulate Impedance Spectroscopy data and allow comparison with, and interpretation of, experimental data; (b) Modelling of functional oxides: point defects, electronic band structure calculations and mass diffusion in ceramics; this will underpin the experimental programmes on the development of new materials and the role of dopants in existing materials. Work packages I and II will be supported by a wide range of characterisation techniques available at Leeds and Sheffield for studying bulk and interfacial phenomena. New characterisation techniques will be applied: aberration-corrected TEM allows true atomic scale spectroscopy of interfaces and defects; Kelvin Probe Microscopy gives direct imaging of the work function variation in grain and across grain boundary regions.
Publications
Harrington R
(2012)
Diffraction data of Zn 3 Cu 4 Sb 2 O 12
in Powder Diffraction
Harrington R
(2008)
Phase equilibria, crystal chemistry and polymorphism of Zn7Sb2O12 doped with Cr and Ni
in Materials Research Bulletin
Heath J
(2015)
Simulation of Impedance Spectra for Core-Shell Grain Structures Using Finite Element Modeling
in Journal of the American Ceramic Society
Hernando M
(2013)
Direct Atomic Observation in Powdered 4H-Ba 0.8 Sr 0.2 Mn 0.4 Fe 0.6 O 2.7
in Chemistry of Materials
Hu Y
(2012)
Relaxor-like Dielectric Behavior in Stoichiometric Sillenite Bi 12 SiO 20
in Chemistry of Materials
Idris M
(2012)
The Effect on Cathode Performance of Oxygen Non-Stoichiometry and Interlayer Mixing in Layered Rock Salt LiNi 0.8 Mn 0.1 Co 0.1 O 2-d
in Journal of The Electrochemical Society
Jo W
(2011)
On the phase identity and its thermal evolution of lead free (Bi1/2Na1/2)TiO3-6 mol% BaTiO3
in Journal of Applied Physics
Kalantari K
(2012)
Structural phase transitions in Ti-doped Bi1- x Nd x FeO3 ceramics
in Journal of Applied Physics
Kalantari K
(2011)
Ti-Doping to Reduce Conductivity in Bi 0.85 Nd 0.15 FeO 3 Ceramics
in Advanced Functional Materials
Khaw C
(2012)
Phase equilibria and electrical properties of pyrochlore and zirconolite phases in the Bi2O3-ZnO-Ta2O5 system
in Journal of the European Ceramic Society
Krayzman V
(2013)
Ca K -edge X-ray absorption fine structure in BaTiO3-CaTiO3 solid solutions
in Journal of Applied Physics
Krohns S
(2011)
The route to resource-efficient novel materials.
in Nature materials
Leist T
(2009)
Shift in Morphotropic Phase Boundary in La-Doped BiFeO 3 -PbTiO 3 Piezoceramics
in Japanese Journal of Applied Physics
Len Interrante (Author)
(2009)
What is "Materials Chemistry"?
Levin I
(2009)
Structural changes underlying the diffuse dielectric response in AgNbO 3
in Physical Review B
Levin I
(2010)
Displacive Ordering Transitions in Perovskite-Like AgNb 1/2 Ta 1/2 O 3
in Chemistry of Materials
Li M
(2010)
Influence of Nonstoichiometry on Extrinsic Electrical Conduction and Microwave Dielectric Loss of BaCo 1/3 Nb 2/3 O 3 Ceramics
in Journal of the American Ceramic Society
Li M
(2011)
A link between p -type electrical conduction and microwave dielectric loss in highly ordered Ba(Co 1/3 Nb 2/3 )O 3 ceramics
in Journal of Materials Research
Li M
(2014)
A family of oxide ion conductors based on the ferroelectric perovskite Na0.5Bi0.5TiO3.
in Nature materials
Li M
(2013)
Transformation from insulating p-type to semiconducting n-type conduction in CaCu3Ti4O12-related Na(Cu5/2Ti1/2)Ti4O12 ceramics
in Journal of Applied Physics
Li M
(2012)
The extrinsic origins of high permittivity and its temperature and frequency dependence in Y0.5Ca0.5MnO3 and La1.5Sr0.5NiO4 ceramics
in Journal of Applied Physics
Li M
(2009)
Relaxor ferroelectric-like high effective permittivity in leaky dielectrics/oxide semiconductors induced by electrode effects: A case study of CuO ceramics
in Journal of Applied Physics
Li M
(2011)
Extrinsic origins of the apparent relaxorlike behavior in CaCu3Ti4O12 ceramics at high temperatures: A cautionary tale
in Journal of Applied Physics
Liu Y
(2009)
Ho-doped BaTiO3: Polymorphism, phase equilibria and dielectric properties of BaTi1-xHoxO3-x/2: 0=x=0.17
in Journal of the European Ceramic Society
Liu Y
(2009)
Synthesis, structure and properties of the hexagonal perovskite, h-BaTi1-xHoxO3-x/2
in Journal of Materials Chemistry
Liu Y
(2012)
Semiconductor-Insulator Transition in Undoped Rutile, TiO 2 , Ceramics
in Journal of the American Ceramic Society
Liu Y
(2013)
Semiconductivity in Acceptor-Doped BaTi 1- x Ho x O 3- x /2-d/2
in Journal of the American Ceramic Society
MacLaren I
(2015)
On the origin of differential phase contrast at a locally charged and globally charge-compensated domain boundary in a polar-ordered material.
in Ultramicroscopy
MacLaren I
(2013)
Local stabilisation of polar order at charged antiphase boundaries in antiferroelectric (Bi0.85Nd0.15)(Ti0.1Fe0.9)O3
in APL MATERIALS
Manan A
(2012)
The effect of processing conditions on the phase, microstructure and dielectric properties of SrCa4Nb4TiO17 and Ca5Nb4TiO17 microwave ceramics
in Materials Science-Poland
Masó N
(2012)
Electrical Properties of Ca-Doped BiFeO 3 Ceramics: From p -Type Semiconduction to Oxide-Ion Conduction
in Chemistry of Materials
Masó N
(2010)
A new family of ferroelectric materials: Me2Nb4O11 (Me = Na and Ag)
in Journal of Materials Chemistry
Masó N
(2010)
Field enhanced bulk conductivity of acceptor-doped BaTi1-xCaxO3-x ceramics
in Applied Physics Letters
Masó N
(2011)
Frequency-dependent electrical properties of ferroelectric BaTi2O5 single crystal
in Journal of Applied Physics
Masó N
(2011)
Polymorphism, structural characterisation and electrical properties of Na2Nb4O11
in Journal of Materials Chemistry
McCabe E
(2010)
New high permittivity tetragonal tungsten bronze dielectrics Ba2LaMNb4O15: M=Mn, Fe
in Journal of Solid State Chemistry
Miao S
(2009)
Polar order and diffuse scatter in Ba(Ti1-xZrx)O3 ceramics
in Journal of Applied Physics
Miranda L
(2010)
Polytypism in the BaMn 0.85 Ti 0.15 O 3-d System (0.07=d=0.34). Structural, Magnetic, and Electrical Characterization of the 9R-Polymorph
in Chemistry of Materials
Miranda L
(2009)
Composition-Structure-Property Relationships of 6H- and 12R-Type Hexagonal Ba(Mn,Ti)O 3-d Perovskites
in Chemistry of Materials
Miranda L
(2011)
Structure-Composition-Property Relationships of 6H-BaTi 1- y Co y O 3-d (0.1 = y = 0.4)
in Chemistry of Materials
Miranda L
(2012)
Structure-property relations in anion deficient 5H- and 3C-polytype Ba(Ti,Co)O3-d perovskites
in Journal of Materials Chemistry
Miranda L
(2009)
Mn-Rich BaMn 1- x Fe x O 3-d Perovskites Revisited: Structural, Magnetic, and Electrical Properties of Two New 6H' Polytypes
in Chemistry of Materials
Osman R
(2011)
Electrical characterization and equivalent circuit analysis of (Bi1.5Zn0.5)(Nb0.5Ti1.5)O7 Pyrochlore, a relaxor ceramic
in Journal of Applied Physics
Osman R
(2011)
Bismuth Zinc Niobate Pyrochlore, a Relaxor-Like Non-Ferroelectric
in Journal of the American Ceramic Society
Palizdar M
(2012)
Crystallographic and magnetic identification of secondary phase in orientated Bi5Fe0.5Co0.5Ti3O15 ceramics
in Journal of Applied Physics
Pasero D
(2008)
Oxygen Nonstoichiometry and Phase Transitions in LiMn[sub 1.5]Ni[sub 0.5]O[sub 4-d]
in Journal of The Electrochemical Society
Perejón A
(2013)
Electrical Properties of Stoichiometric BiFeO 3 Prepared by Mechanosynthesis with Either Conventional or Spark Plasma Sintering
in Journal of the American Ceramic Society
Pokorný J
(2011)
Use of Raman spectroscopy to determine the site occupancy of dopants in BaTiO3
in Journal of Applied Physics
Prades M
(2010)
Field enhanced bulk conductivity of BaTiO3 : Mg ceramics
in Journal of Materials Chemistry
| Description | Ian Reaney (IR): The part of the grant for which IR was directly responsible concerned materials processing. The major breakthrough in this area was the establishment of multilayering technology at Sheffield via Denis Cummings (PDRA). This facility generated several articles in referreed journals but importantly has become the backbone of the group in terms of prototype device capability and feeds into many projects including the recently awarded grant 'Substitution and Sustainability in Functional Materials' Anthony West (AW): The main discovery is the effect of bias voltage on the electrical properties of bulk ceramic materials that have been doped by an acceptor mechanism. Six publications have followed on alkaline earth titanates with the perovskite structure and one on doped bismuth ferrite which shows a remarkable insulator-metal transition at room temperature. This work is likely to expand to consider situations under which oxygen in oxides can be redox active John Harding (JH) was responsible for the modelling part of the grant. Working in collaboration with Derek Sinclair (DS) the modelling showed that the widely accepted mechanism to produce semiconducting grains (direct donor-doping) in PTCR BaTiO3-based thermistors is incorrect and demonstrated an alternative based on Ti vacancies. We have made a major code development to analyse impedance spectra. A fast, efficient finite element code now enables direct analysis (i.e. no equivalent circuits) of impedance spectra for three dimensional heterogeneous ceramics with realistic micro-structures of ceramics and incorporating contacts, grain boundaries, and grain cores. Derek Sinclair (DS) developed structure-composition-property relationships in several important perovskite-type oxides. Particular emphasis was given to the electrical properties that ranged from dielectrics to semiconductors to ionic conductors. Systems studied included A-site ordered perovskites such as CaCu3Ti4O12, B-site deficient hexagonal perovskites such as Ba3LaNb3012 and A-site disordered cubic type (Na,Bi)TiO3 (NBT). A major discovery in this work was high levels of oxide-ion conductivity in NBT and this has led to the development of a new family of oxide ion conductors with potential as electrolytes for intermediate temperature solid oxide fuel cells. |
| Exploitation Route | AW: The discovery of voltage-dependent conductivity of electrical properties should impact on a number of areas, including dielectric breakdown of insulating ceramics, mechanisms of memristive switching and the onset of flash sintering, all of which are pursued by numerous research groups elsewhere.IR: The tapecasting/screen printing methodologies introduced by this grant have been shown to be very useful for projects ranging from the development of thermoelectric generators to carbon capture and utilisation; these are either planned or in progress. JH: The finite element code will be of wide utility for impedance spectra analysis and can be extended to consider thermistors and piezoelectric systems. DS: The discovery of oxide-ion conductivity in NBT was unexpected and raises the potential for other new families of Bi-based perovskites oxide as a new class of solid electrolytes. These materials may have applications in Solid Oxide Fuel Cells. |
| Sectors | Aerospace Defence and Marine Education Electronics Energy |
| Description | IR: The major findings in establishing a tape casting/screen printing capability have been used to generate significant amounts of further funding and have become intrinsic to Sheffield's research portfolio, generating >£3M in related projects AW: Recognition of the voltage-dependence of p-type semiconductivity in some ceramic oxides and attribution of its origin to redox-active oxygen has changed my perspective of p-type semiconduction. Grant applications have been submitted as a direct consequence with results awaited on SOCRATES (epsrc: degradation of fuel cells call), DOLORES (EU Marie-Curie fellowship application) and NORA (EU Advanced fellowship application). DS- The initial NBT results on oxide-ion conduction have generated a follow up EPSRC grant award (due to start Dec 2014) to optimise the electrical properties in this system and to explore the possibility of using NBT as a bilayer electrolyte component for intermediate temperature solid oxide fuel cells. |
| First Year Of Impact | 2012 |
| Sector | Aerospace, Defence and Marine,Education,Electronics,Energy |
| Impact Types | Economic |
| Description | EPSRC RESPONSIVE MODE GRANT |
| Amount | £467,000 (GBP) |
| Funding ID | EP/L027348/1 |
| Organisation | Engineering and Physical Sciences Research Council (EPSRC) |
| Sector | Public |
| Country | United Kingdom |
| Start | 11/2014 |
| End | 10/2017 |
| Description | Global Challenges PhD studentship |
| Amount | £60,000 (GBP) |
| Organisation | Engineering and Physical Sciences Research Council (EPSRC) |
| Sector | Public |
| Country | United Kingdom |
| Start | 09/2013 |
| End | 09/2017 |
| Description | Marie-Sklodowska-Curie Individual Fellowships |
| Amount | £138,981 (GBP) |
| Organisation | European Commission |
| Sector | Public |
| Country | European Union (EU) |
| Start | 09/2016 |
| End | 09/2018 |
| Description | Materials for Demanding Environments |
| Amount | £139,200 (GBP) |
| Funding ID | 67856-475270 |
| Organisation | Innovate UK |
| Sector | Public |
| Country | United Kingdom |
| Start | 04/2016 |
| End | 04/2017 |
| Description | Royal Academy of Engineering Distinguished Visitor |
| Amount | £6,000 (GBP) |
| Organisation | Royal Academy of Engineering |
| Sector | Charity/Non Profit |
| Country | United Kingdom |
| Start | 03/2017 |
| End | 11/2017 |
| Description | Centre for Dielectrics and Piezoelectrics (CDP |
| Organisation | Center for Dielectrics & Piezoelectrics |
| Country | United States |
| Sector | Learned Society |
| PI Contribution | Centre for Dielectrics and Piezoelectrics (CDP). Sheffield has now been voted in as an Affiliate Partner in the NSF funded CDP alongside North Carolina State University (NCSU) and Pennsylvania State University (PSU. The CDP has ~25 members which include Samsung, Apple, Murata and 3M. The joint grant with PSU was instrumental in cement our relationship with the centre based on a number of high profile publications with the CDP co-director Susan Mckinstry (international CoI on grant) |
| Collaborator Contribution | Susan McKinstry and Ian M. Reaney are now co-directors of the CDP. The publications helped demontrate to the Industrial Members the strength of the partnership between the CDP and Sheffield |
| Impact | Multidisciplinary. Ceramic Engineering, Life Cycle Assessment, Materials Modelling. Has led to joint projects, research, secondments and industrial funding |
| Start Year | 2017 |
| Title | Fibre-reinforced polymer matrix |
| Description | A self-healing composite material comprises a fibre-reinforced polymer matrix containing a thermosetting polymer and a thermoplastic polymer that together form a solid solution. The reinforcing fibres may be carbon fibres forming one or more layers. Preferably, the thermosetting polymer is an epoxy resin and the thermoplastic polymer is polybisphenol-A-co-epichlorohydrin. A method for forming the composite is also disclosed, whereby a solution of a prepreg of the thermosetting and thermoplastic polymers may be used to impregnate a layer of reinforcing fibres before curing the thermosetting polymer. In another aspect, the composite comprises a fibre-reinforced polymer matrix containing a thermosetting polymer and a thermoplastic polymer with a damage detection system. The detection system may detect changes in acoustic wave propagation or resistance. Any damage may be repaired by a method in which the affected area is heated to the fusion temperature of the thermoplastic polymer, for example, by passing a current through the fibres. |
| IP Reference | GB2421953 |
| Protection | Patent granted |
| Year Protection Granted | 2006 |
| Licensed | No |
| Impact | Not known as the pi responsible retired 5 years ago |
| Title | High Temperature Piezoelectric Ceramics |
| Description | A patent has been filed by Professor Bell, Leeds University, in multiple territories covering new piezoelectric compositions with properties comparable to the market leader, PZT, but with a much wider operating temperature window. |
| IP Reference | EP11738766.6 |
| Protection | Patent application published |
| Year Protection Granted | 2014 |
| Licensed | No |
| Impact | This is an ongoing research area at Leeds to find alternative, lead-free piezoelectric materials |
| Title | Polymer electrolyte |
| Description | A polymer based electrolyte complex is configured to provide ion transport, the complex comprising: a plurality of ion conducting polymers, each polymer of the plurality of polymers comprising an amphiphilic repeating unit. The polymers are arranged as a lattice of ionophobic repeating unit regions and ionophilic repeating unit channels. The channels are configured to provide ion transport. A first ionic bridge polymer is positioned substantially between the lattice. The ionic bridge polymer is configured to allow ion transport between the ionophilic repeating unit channels of the lattice. The complex further comprising and is characterised by: a second ionic bridge polymer positioned substantially between the lattice. The second ionic bridge polymer is configured to allow ion transport between the ionophilic repeating unit channels of the lattice. |
| IP Reference | GB2401608 |
| Protection | Patent application published |
| Year Protection Granted | 2004 |
| Licensed | No |
| Impact | This has lead other research groups, worldwide, to consider such materials |
| Company Name | Ionix |
| Description | Ionix develops piezoelectric materials (materials that generate electricity when pressure is exerted on them) that it claims can operate in high temperature, high work environments. |
| Year Established | 2011 |
| Impact | It is now an established organisation providing commercial high temperature electroceramics |
| Website | http://www.ionixadvancedtechnologies.co.uk |
| Company Name | Ionix |
| Description | Ionix develops piezoelectric materials (materials that generate electricity when pressure is exerted on them) that it claims can operate in high temperature, high work environments. |
| Year Established | 2011 |
| Impact | Too soon to describe |
| Website | http://www.ionixadvancedtechnologies.co.uk |