Abstract:

Nb-containing capacitor material on foamed nickel substrate was prepared by the hydrothermal reaction with ammonium niobium oxalate and glucose as the starting meterials. The prepared samples was characterized by infrared spectroscopy(FTIR), scanning electron microscopy(SEM), X-ray diffraction(XRD) and electrochemical testing. By comparation of surface topography of products under different conditions, the optimal conditions of hydrothermal reaction for preparing Nb-capacitor material are established as:the molar ratio of glucose and ammonium oxalate is 7:1, and reaction temperature and time are 200 ℃ and 18 h, respectively. The Nb-containing oxide loaded on the foamed nickel is 0.3707 g/cm². The maximum capacity of Nb-containing capacitor material reaches 189.47 F/g at the current density of 0.5 A/g. After 1000 cycles, the discharge capacitance of holding rate remains at 95%. This indicates that it is a promising candidate as the super capacitor materials.

Key words: nickel foam, niobium-capacitance material, current density, capacitance