Zinc ion induced three-dimensional Co9S8 nano-neuron network for efficient hydrogen evolution

• Published in: Renewable energy 2020-09, Vol.157, p.415-423
• Main Authors: Dong, Bin, Xie, Jing-Yi, Wang, Nan, Gao, Wen-Kun, Ma, Yu, Chen, Tian-Shu, Yan, Xin-Tong, Li, Qing-Zhong, Zhou, Yu-Lu, Chai, Yong-Ming
• Format: Article
• Language: English
• Subjects: Co9S8; Electrocatalyst; Hydrogen evolution reaction; Nano-neuron network; Zn-doping
• ISSN: 0960-1481; 1879-0682
• DOI: 10.1016/j.renene.2020.05.057

As the cost-effective and nontoxic alternative for hydrogen evolution reaction (HER), Co9S8 has attracted much attention. This paper explores the regulation of Zn doping impacted the unique nanostructure and electrocatalytic performance on Co9S8. Herein, utilizing copper foam (CF) as substrate, a series of different nanostructure of (Zn-)Co9S8@CF has been synthesized by accurately varying the ratio of Zn2+ to Co2+. Compared with aggregated pure Co9S8 and other different ratios contrast samples, Zn–Co9S8@CF-(1-1) with a zinc to cobalt ratio of 1 possesses highly dispersity which can be attributed to the novel nano-neuron network structure. The electrochemical measurements for HER demonstrate that Zn–Co9S8@CF-(1-1) not only reveals superior activity with small overpotentials to achieve a current density of 10 mA cm−2 in acidic (278 mV) and alkaline (273 mV) media, but also exhibits long-time durability in the solution with a wide range of pH. The excellent performance of Zn–Co9S8@CF-(1-1) can be attributed to the unique reticular structure which can facilitate exposure of numerous active sites and favorable long-term stability. The substrate of three-dimensional CF can provide the remarkable conductivity. This work provides a precise and effective approach to regulate three-dimensional nanostructure of Zn-doped electrocatalysts for HER. [Display omitted] •Zn–Co9S8 on copper foam (CF) with a nano-neuron network structure is synthesized.•The ratios of Zn2+ to Co2+ can affect the structure of Zn–Co9S8@CF.•Zn–Co9S8@CF exhibits excellent activity and long-time durability with a wide range of pH.•Zn doping is a promising method for construct the novel structure of electrocatalysts.