Ni(OH)2/CoS heterostructure grown on carbon cloth for robust supercapacitor and methanol electrocatalytic oxidation

• Published in: Electrochimica acta 2023-03, Vol.443, p.141980, Article 141980
• Main Authors: Wang, Guosheng, Xu, Zhihua, Li, Zhikun, Ding, Yingjie, Ge, Ruixiang, Xiang, Ming, Wang, Geming, Yan, Zhaoxiong
• Format: Article
• Language: English
• Subjects: Electrode material; Heterostructure; Hierarchical structure; Hybrid supercapacitor; Methanol electro-oxidation
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2023.141980

•Ni(OH)2/CoS hybrid is successfully immobilized on carbon cloth (Ni(OH)2/CoS /CC).•CoS mediation greatly boosts the electrochemical performance of Ni(OH)2/CC.•Ni(OH)2/CoS/CC has a ultra-high specific capacity and excellent capacity retention.•Ni(OH)2/CoS/CC//AC device possesses a marvelous energy density.•Ni(OH)2/CoS/CC has an enhanced catalytic activity toward methanol electro-oxidation. Heterojunction construction is a promising strategy to enhance the charge transfer efficiency, which subsequently optimizes the utilization of the electrode material. Herein, the constructed Ni(OH)2 nanosheets on ZIF-67-derived CoS core deposited on carbon cloth (Ni(OH)2/CoS/CC) possesses a superior performance (561.6 mA h g–1 at 1 A g–1) to Ni(OH)2/CC electrode (199.4 mA h g–1). Hybrid supercapacitor (HSC) with a Ni(OH)2/CoS/CC cathode and an active carbon (AC) anode (Ni(OH)2/CoS/CC//AC) provides a remarkable energy density of 90.8 W h kg–1 at 800 W kg–1 and keeps 59.7 W h kg–1 even at 25,600 W kg–1, higher than most of the reported Ni(OH)2-related device, and possesses a marvelous capacity retention of 92.2% over 10,000 charge-discharge cycles. Concurrently, Ni(OH)2/CoS/CC as an efficient electrocatalyst displays an excellent electro-catalytic activity towards methanol oxidation. The outstanding electrochemical performance of Ni(OH)2/CoS/CC is chiefly due to the mediation of the Co2+/Co3+ redox cycle for the rapid conversion of Ni2+ into Ni3+, which greatly boosts the charge-transfer efficiency in the supercapacitors and methanol electro-oxidation. This work provides a rational way to obtain high-power electrode material for supercapacitors (SCs) and electrocatalytic methanol oxidation in direct methanol fuel cells (DMFCs). [Display omitted]