Growth of phosphorus-substituted Ni–Co–S and iron oxide nanosheets on N-doped carbon nanofibers for high performance hybrid supercapacitor

Abstract

Abstract Herein, the phosphorus-substituted nickel cobalt sulfides nanosheet arrays growth on nitrogen doped carbonic nanofibers (donated as Ni–Co–S–P) are prepared by an electrodeposition method. The morphologies and chemical composition of Ni–Co–S–P are investigated by SEM, TEM, XPS and EDS. The electrochemical properties of Ni–Co–S–P are tested by CV, GCD and EIS technologies. And the sample Ni–Co–S–P-4 displays the most outstanding electrochemical properties including electrocatalytic activity, rate capability and specific capacitance. In addition, the iron oxide nanosheets growth on N-CNFs (Fe–O/N-CNFs) are prepared by the same electrodepositing route. And they can serve as a negative electrode according to the electrochemical performances analysis. A hybrid supercapacitor based on the obtained electrodes is further assembled by using Fe–O/N-CNFs as negative electrode and Ni–Co–S–P as positive electrode. The as-fabricated hybrid supercapacitor show outstanding energy storage performance, it possesses a high energy density at 55.8 Wh·kg−1 corresponding to a power density at 402.9 W kg−1.