RESEARCH INTERESTS:
1. Facet engineered nanocrystals
In general, well-defined single crystal surfaces are model systems which known to exhibit surface- sensitive catalytic, electrocatalytic and photocatalytic properties and efforts are therefore made to translate the findings to bulk nanomaterials of practical importance. SHAPECAT is aiming at design and synthesis aspects of nanocrystals of different shapes of various metals (Pd, Pt, Ag, Au, Cu) and semiconductors (TiO 2 , BiVO 4 ) of high selectivity in size, shape and composition. Further, the reagents used for the synthesis of size- and shape-controlled nanoparticles adsorb strongly on the surface and they adversely impact the surface properties. In this regard, surfactant removal from the shape-controlled nanoparticles is inevitable to study catalytic and electrocatalytic reactions. SHAPECAT is addressing on how to clean the nanoparticle surfaces by employing various methods such as solution phase methods, physical methods etc. In addition, SHAPECAT is interested in exploring the facet-engineered and well- integrated hybrid nanocrystals (Semiconductor (oxide based)/Metal) for catalytic and photocatalytic applications.
2. Design of thin film based reactors (possibly scalable) for solar fuels and chemicals synthesis
For instance, H2 production from the particulate form of photocatalyst is hindered by several limitations; (a) decrease the efficiency to half when increase the loading to double due to inadequate material exposure to light, (b) prevalent light scattering rather than light absorption and therefore decrease in charge generation, (c) material disintegration due to mechanical forces which are persistent from the stirring, and (d) heavy material and infrastructure requirements which further increase the cost of hydrogen production. These issues can be successfully circumvented by taking the powder form of catalyst into thin film over a ordinary substrate. This approach is the inspiration from a leaf where all the components interconnected towards never ending photosynthesis process. In contrast to solar cell where electrons are needed to travel several microns distance to reach the contact, thin film photocatalysis provide the charge carriers locally and instantaneously utilize the charge carriers and complete the reaction that led to efficient hydrogen production. Not only aiming at the design of novel materials, SHAPECAT will be exploring on the design possibilities of reactor with features of efficient and cost viable manner for synthesis of valuable chemicals (methanol, ammonia, ethanol) and fuels (H2) using inexhaustible resources (Water, CO2, N2, CH4 and sunlight).
Ms. Asha Devi K. S.