Bimetallic cobalt-nickel selenide@polypyrrole core-shell nanotubes 011 nickel foam as high-performance electrode material for supercapacitors

Abstract

In this paper, bimetallic Co-Ni selenide@polypyrrole core-shell nanotubes on nickel foam (CoNi0.4Se@PPy/NF) were synthesized according to a two-step hydrothermal reaction and an electrodeposition process. It was developed to be an electrode material for supercapacitors. This economical CoNi0.4Se @PPy/NF electrode was highly conductive, and its specific areal capacitance at 5 mA cm-2 was as high as 13.27 F cm-2. In addition, it showed good cycling stability. After 1000 cycles at 30 mA cm-2, CoNi0.4Se@PPy/NF retained 92.63% of its capacitance. It was suggested that its superior electrochemical properties were due to its great specific capacitance as well as to the electrical conductivities obtained from the synergy between selenide and polypyrrole and the unique structure of the core-shell and nanotubes. The above results showed that the CoNi0.4Se@PPy core-shell nanotube composite material was a promising electrode material for supercapacitors.