Professor Pratibha Gai
Surface Science, Catalysis, Nanomaterials, Atomic scale Dynamic In-situ Electron Microscopy Developments for visualising gas molecule-catalyst reactions at the atomic level
Our current research programmes are in the following areas:
- Heterogeneous Catalysis
- Development of novel aberration-corrected in-situ electron microscopy to visulaise gas molecule-solid catalyst surface reactions at the atomic level, in real-time.
- Atomic scale aberration-corrected In-situ electron microscopy in the development of NSAID pharmaceuticals
- Bioenergy; development of nanoscale materials for the production of biofuels
- Novel nanocatalysts for Fuel Cells;
- The preparation of novel nanocatalysts and fundamental understanding of atomic processes in Fischer-Tropsch (FT) processes,
- Nanomaterials and Single Atoms
- Applications include, three-dimensional nanostructure and specific areas of noble metal-doped-porous titania systems of interest in hydrogen energy and wastewater treatment, using aberration corrected electron microscopy (AC-EM), electron tomography, modelling and physico-chemical methods
- Development of nickel nanodots on amorphous silica in the permselectivity for hydrogen separation in reforming catalytic reactions for hydrogen production
- Nanostructures and growth mechanisms in nanoscale tetrapods, nanowires and nano-twinned metals which exhibit remarkable strength and structural stability
- Bio-nanotechnology for biomedical applications
Our approaches include the development and application of Angstrom scale (0.1 nm) dynamic aberration-corrected transmission electron microscopy (Fig.1) and related analytical spectroscopy tools at the York JEOL Nanocentre to probe dynamic catalysis at the atomic level, in real-time, under controlled conditions of temperature and environment, related to the real world. This capability allows us to follow dynamic changes in nanocatalysts to elucidate reaction mechanisms, explore transient states under reaction conditions and to control changes in catalyst stability leading to active nanostructures/sites. The data are correlated with activity easurements to understand structure-property relationships. This information is crucial for the development of advanced catalysts and green processes. These methods are also used in the design and synthesis of new nanomaterials, especially nanoparticle composites, their structure and properties.
Professor E D Boyes, Dr K Yoshida, Professor N Tanaka, Professor J R Weertman et al. and with UK Chemical Industry.
Fig. 1: Centre: JEOL 2200 FS TEM/STEM with dual aberration correctors at the York JEOL Nanocentre, University of York.
LHS: Silicon <110> atom columns with 0.136 spacing.
Bottom: Atomic scale image of gold nanocatalyst particle with (111) surface steps. The (111) lattice spacings of 0.23 nm are clearly revealed.
(P L Gai and E D Boyes, Microscopy Research and Technique
, 2009, 73, 153; and Journal of Physics
, (IOP) 2010, 241
Fig.2: Atomic scale active species in tungstated zirconia nanocatalyst for NSAIDS (Catalysis Sc. And Technology (RSC); 2011; DOI: 10.1039/c0cy00063a)