Solution Precursor Plasma Spray Deposition of Super-capacitor Electrode Materials

Double layer capacitors owe their large capacitance to high specific surface area carbon-based electrode materials adhered to a current collector via an adhesive. However, recent studies attribute greater electrical energy storage capacity to transition metal oxides/nitrides: a new generation of electrode materials for use in super-capacitors with mixed double-layer and pseudo-capacitive properties. Solution precursor plasma spray deposition is a technique that allows coatings to be fabricated with fine grain sizes, high porosity levels, and high surface area; characteristics ideal for application as super-capacitor electrodes. This investigation established conditions for deposition of porous, high specific surface area α-MoO3. It further identified a two-step temperature-programmed reaction for topotactic phase transformation of the α-MoO3 deposits into high specific surface area molybdenum nitrides of higher conductivity and higher electrochemical stability window. The electrochemical behavior of molybdenum oxide/nitride deposits was also studied in order to assess their potential for use in super-capacitors.MAS