Fabrication of ultrathin CoMoO4 nanosheets modified with chitosan and their improved performance in energy storage device

Ultrathin nanosheet-assembled cobalt molybdate (CoMoO 4 ) with a mesoporous morphology was synthesized by a urea-assisted solution combustion route at a temperature of 400 °C. The as-prepared CoMoO 4 was modified using chitosan cross-linked with glutaraldehyde (glu) and employed as a cathode material in an aqueous hybrid capacitor. The physical and electrochemical behaviour of CoMoO 4 modified with chitosan and the as-prepared (chitosan free) CoMoO 4 has been compared and discussed. The modified CoMoO 4 exhibited excellent electrochemical performance with a specific capacitance of 135 F g −1 at 0.6 A g −1 and an energy density of 31 W h kg −1 . It also exhibited good cycling stability with high coulombic efficiency over 2000 cycles retaining a specific capacitance of 81 F g −1 at 3 A g −1 , comparatively much better than that of nanostructured chitosan free CoMoO 4 which yielded 17 F g −1 . The results indicated that chitosan gel strongly adheres to the molybdate moiety of CoMoO 4 and increases the capacitance four-fold compared to a chitosan free material. The modified CoMoO 4 electrode shows potential for high performance, and is an environmentally friendly and low-cost energy storage device. Ultrathin nanosheet-assembled cobalt molybdate (CoMoO 4 ) with a mesoporous morphology was synthesized by a urea-assisted solution combustion route at a temperature of 400 °C.