Pt/Metal Oxide Micro-Nanostructures for Chemical-Electrical Signal Transduction

Investigation of heterogeneous catalysis using bifunctional systems of nanodispersed Pt on porous oxide structures is important for a broad range of applications including photocatalysis, fuel cells, solid state chemical sensors, and others. Active transducers exhibit great potential through their ability to convert surface-released chemical energy into electrical signal. We report on a class of nanocomposite mesoporous systems that generate this electrical signal when subjected to catalytic oxyhydrogen reactions of their surface; these systems include, but are not limited to, mesoporous TiO₂ decorated with electrically continuous arrays (meshes) of Pt nanoparticles. It has been proposed that the proton spillover hypothesis of the electromotive force in the mesoporous chemical-electrical transducer nanostructure leads to a multi-modal nature of the “chemicurrent” - non-thermal electrical signals related to hot electron and e-h pair generation.  Structural and surface morphology play a pivotal role in the generation, transport, and recombination of electrical charge in these bifunctional catalytic systems. In this presentation, we discuss plasma electrolytic oxidation procedures that allow for the further optimization of mesoporous nanocomposite structures by controlling parameters such as pore density within the samples.