Synthesis of Zn doped CrV spinel oxide nanostructures for flexible supercapacitor and hydrogen evolution reaction

Nanostructures containing mixed transition metal oxides with various architectures have been used as promising materials in supercapacitors due to their excellent capacitive contributions. The present work reports on the spinel zinc chromium vanadate ZnCrVO4 (ZCV) nanostructures fabricated via the facile hydrothermal method, for the first time. The pseudocapacitive nature and promising electrocatalytic hydrogen evolution of the prepared ZCV in activated carbon electrodes were confirmed by electrochemical tests. The maximum specific capacitance (Cs) of 448 F g−1 at 1 mA was determined for the ZCV nanostructures s which is far better than pure chromium vanadate (CrV). ZCV containing supercapacitor exhibited the specific energy of 54.5 Wh kg−1 at a power of 1350 W kg−1 and the remarkable coulombic efficiency of the device was recorded at around 99% at 10.000 cycles. In addition, excellent electrochemical hydrogen evolution reaction (HER) kinetics for ZCV were revealed by the Tafel slope (118 mV dec−1) which is quite comparable to the slope of the Pt–C electrode (54 mV dec−1) under the same operating conditions.