Pulse-reversal deposition of Ni3S2 thin films on carbon fiber cloths for supercapacitors

Abstract

In this present work, nanoporous net-like Ni3S2 thin films were successfully electrodeposited on flexible carbon fiber cloths (CFCs) through a facile one-step pulse-reversal electrodeposition (PR) method. The effects of pulse frequency of the PR deposition mode on the microstructure evolution of the deposits and their corresponding capacitance properties as electroactive electrodes for supercapacitors were investigated systematically. After the optimization of pulse frequency, the optimized flexible Ni3S2 electrode was found to be with the unique well-interconnected net-like nanoporous. The subsequent galvanostatic charge-discharge studies showed that the optimized Ni3S2 electrode delivered a superior specific capacitance of about 600 F/g at a constant current density of 1 A/g with 75% capacitance retention even after at relatively high current density of 8 A/g. Moreover, the optimized Ni3S2 electrode retained the 84.6% of initial discharge capacitance after the cycling test at current density of 2 A/g for 2000 cycles. According to the aforementioned electrochemical performance, the NSPR-2 electrode with nanoporous net-like nanostructure could be a potential binder-free electrode for flexible supercapacitors.