Design and Construction of Cu(OH)2/Ni3S2 Composite Electrode on Cu Foam by Two-Step Electrodeposition.

Sa Lv,Peiyu Geng,Huan Wang,Chao Wang,Xuefeng Chu,Jia Yang,Wenshi Shang,Xiaotian Yang,Yaodan Chi

doi:10.3390/mi13020237

Abstract

A Cu(OH)2/Ni3S2 composite has been designed and in situ constructed on Cu foam substrate by facile two-step electrodeposition. Cu(OH)2 is achieved on Cu foam by galvanostatic electrodeposition, and the subsequent coating of Ni3S2 is realized by cyclic voltammetric (CV) electrodeposition. The introduction of Cu(OH)2 provides skeleton support and a large specific surface area for the Ni3S2 electrodeposition. Benefiting from the selection of different components and preparation technology, the Cu(OH)2/Ni3S2 composite exhibits enhanced electrochemical properties with a high specific capacitance of 4.85 F cm−2 at 2 mA cm−2 and long-term cyclic stability at 80.84% (4000 cycles).

Highlights

Two-Step Electrodeposition.Recently, transition metal sulfides—especially nickel sulfide—such as NiS, Ni3 S2, Ni9 S8 have attracted extensive attention as a promising cathode for supercapacitors [1,2,3]
Cu foam (70 PPI, 1.8 mm thick, Kunshan DESSCO Co., Ltd., Kunshan, China) was cut into 1 × 1.5 cm2 slices, and the slices were washed in dilute hydrochloric acid, acetone, ethanol and deionized water to remove the surface oxide layer
The Cu(OH)2 obtained in the previous step served as working electrode, and saturated calomel electrode (SCE) and Pt plate served as reference and counter electrode, respectively

Summary

Introduction

Transition metal sulfides—especially nickel sulfide—such as NiS, Ni3 S2 , Ni9 S8 have attracted extensive attention as a promising cathode for supercapacitors [1,2,3] Compared with their corresponding oxides and hydroxides, transition metal sulfides have better conductivity and electrochemical activity due to the lower electronegativity of sulfur [4,5]. These available nickel-sulfide-based electrode materials still have problems, such as low-rate capability and restricted electrochemical redox reaction kinetics at large current density. The enhanced capacitance is ascribed to backbone support of ZnO array, which provides a large specific surface area for subsequent growth of

Methods

Results

Conclusion