Intermetallic Molybdenum Carbide for Pseudocapacitive Electrode Material.

Nanocrystalline intermetallic Mo2C has been synthesized via carbonizing of molybdenum oxides and studied as a capacitive material for electrochemical energy storage. A specific capacitance of 218 F g_-1 is found in aqueous 1 mol dm-3 H2SO4 at 20°C using a specific current density of 1 A g_-1, with 5.3% loss of capacitance being experienced after 10000 cycles of charging-discharging. 88.5% of the initial value remains at a specific current density of 10 A g_-1. Electrochemical capacitance of Mo2C may be attributed to its electrical conductivity and nanostructure that can promote the electrochemical performance observably and ensure a long cycle life and electrical charge transfer. The assembled asymmetrical Mo2C//AC electrochemical capacitor shows an energy and power density of 23.5 W h kg_-1 and 9028.8 W kg_-1, facilitating duty applications. [ABSTRACT FROM AUTHOR]