NSF: Direct Imaging of Charge Distribution in Ceramic Materials
Lead Research Organisation:
University of Oxford
Department Name: Materials
Abstract
If one knew the positions of all the electrons in a material, there would be no need to find where the nuclei are . This is a very strong statement, and whilst it may not true in all possible cases, for many materials it is. Whilst there have been developments in our ability to determine the local structure of materials at atomic resolution in projection almost all of these have focused on locating the atom positions. The more difficult problem of determining the positions of the electrons is much less well developed but, if possible would provide a new dimension of information in materials research. If successful, the potential application of this type of data is very wide ranging and includes studies of catalysis; as new dielectric, ferroelectric and in some cases magnetic devices and in oxygen transport membranes and fuel-cells; it is also critical to the understanding at the atomic level of many corrosion problems. These studies will also provide a rich seam of experimental data against which theoretical models can be compared and calibrated at far higher precision than is currently possible. Our proposed research therefore poses a Grand Challenge , namely the experimental determination of local charge distribution in ceramic materials at the nanoscale with particular reference to studies of individual defects. To understand the effects of charge distribution on material properties we intend to develop methods for directly imaging charge . In particular we wish to examine the redistribution of charge at surfaces and defects which are often crucial to materials properties and device performance. To achieve this we will develop experimental methods for imaging charge using both Scanning Tunneling Microscopy (STM) and aberration corrected High Resolution Transmission Electron Microscopy (HRTEM). We will also compare results from these two techniques which provide complementary information. This project will span two internationally leading institutions, one in the UK and one in the USA each of which has access to unique instrumentation and computation for this purpose. Each part of the proposal will deliver new general methodologies and we will utilize these in pioneering experiments involving a range of technologically important materials. Funding for this project will support two post doctoral research fellows working at each of the collaborating institutions together with travel costs to enable members of both research teams to work in the collaborating laboratories.
Publications
Ciston J
(2011)
Optimized conditions for imaging the effects of bonding charge density in electron microscopy.
in Ultramicroscopy
Ciston J
(2009)
Real-space Measurements of Bonding Charge Density in Aberration-corrected High Resolution Electron Microscopy
in Microscopy and Microanalysis
Enterkin JA
(2010)
A homologous series of structures on the surface of SrTiO3(110).
in Nature materials
Kim H
(2015)
Resilient High Catalytic Performance of Platinum Nanocatalysts with Porous Graphene Envelope.
in ACS nano
Liberti E
(2016)
European Microscopy Congress 2016: Proceedings
Marks LD
(2015)
Transition from Order to Configurational Disorder for Surface Reconstructions on SrTiO_{3}(111).
in Physical review letters
Marshall MS
(2011)
Surface and defect structure of oxide nanowires on SrTiO3.
in Physical review letters
Marshall MS
(2009)
Shape transitions of epitaxial islands during strained layer growth: anatase TiO2(001) on SrTiO3(001).
in Physical review letters
Mura M
(2012)
Formation mechanism for a hybrid supramolecular network involving cooperative interactions.
in Physical review letters
Mura M
(2010)
Experimental and theoretical analysis of H-bonded supramolecular assemblies of PTCDA molecules
in Physical Review B
Robertson A
(2014)
Inflating Graphene with Atomic Scale Blisters
in Nano Letters
Robertson AW
(2014)
The role of the bridging atom in stabilizing odd numbered graphene vacancies.
in Nano letters
Robertson AW
(2014)
Stability and dynamics of the tetravacancy in graphene.
in Nano letters
Robertson AW
(2015)
Partial Dislocations in Graphene and Their Atomic Level Migration Dynamics.
in Nano letters
Sun J
(2013)
Controlled growth of Ni nanocrystals on SrTiO(3) and their application in the catalytic synthesis of carbon nanotubes.
in Chemical communications (Cambridge, England)
Wang Z
(2016)
Transition from Reconstruction toward Thin Film on the (110) Surface of Strontium Titanate.
in Nano letters
Warner JH
(2012)
Dislocation-driven deformations in graphene.
in Science (New York, N.Y.)
Wu C
(2014)
The effect of the size of surface Pd island ensembles on electron transfer of adsorbed perchlorate ions on Au(111).
in Chemical communications (Cambridge, England)
Wu C
(2013)
Initial growth stages of titanium and barium oxide films on SrTiO3(001)
in Surface Science
Wu C
(2015)
Stoichiometry engineering of ternary oxide ultrathin films: Ba x Ti 2 O 3 on Au(111)
in Physical Review B
Description | Experimental conditions for measuring bonding charge using TEM have been established and applied to complex oxide structures New image simulation methods have been developed to include for the first time the effects of bonding charge on high resolution TEM image contrast |
Exploitation Route | Characterisation of charge distribution in oxide ceramics including defects and surfaces and in nano materials |
Sectors | Education Electronics Energy Other |