The influence of crystal structures on the performance of CoMoO 4 battery-type supercapacitor electrodes.

CoMoO 4 is a promising battery-type supercapacitor electrode material that can offer relatively high storage capacity and cycle stability. In this work, we investigate the role of the crystalline phase of CoMoO 4 in determining these performance parameters. The hydrate phase of CoMoO 4 was synthesized on a nickel foam substrate via hydrothermal reaction with subsequent annealing under an inert atmosphere leading to the formation of the β-phase CoMoO 4 . Similar nanoplate morphologies were observed in all of the samples. The hydrate-phase CoMoO 4 demonstrates larger specific capacity than the annealed β-phase CoMoO 4 . Besides, the samples synthesized at lower temperatures have better rate capability than the sample annealed at higher temperatures. However, the hydrate phase had worse long-term stability compared to the β-phase samples.