Alumina-Titania Nanolaminate Condensers for Hot Programmable Catalysis

Nanolaminates composed of thin alternating layers of Al2O3 and TiO2 (ATO) were engineered by using atomic layer deposition as the dielectric material for a Pt-on-carbon catalytic condenser. Investigation assessed synthesis parameters including the deposition temperature, Al2O3 and TiO2 layer thicknesses, total number of layers, and a capping Al2O3 layer on the maximum charge accumulation in the Pt catalyst. The highest capacitance ATO configuration demonstrated a specific capacitance of similar to 1200 nF/cm(2) with working voltages of +/- 5 V, enabling the storage of 4 x 10(13) electrons or holes per cm(2) at room temperature. The ATO devices exhibited enhanced capacitance at elevated temperatures of up to 400 degrees C, suggesting the suitability of these materials for high-temperature applications. Adsorption of carbon monoxide on the Pt/C-ATO device characterized by grazing incidence infrared spectroscopy showed changes in the surface binding energy of 13.1 +/- 0.8 kJ/mol for an applied external voltage bias of +/- 1 V.