MOF-derived V-CoxP@NC nanoarchitectures for highly enhanced electrocatalytic water splitting through electronical tuning

• Published in: Electrochimica acta 2020-10, Vol.357, p.136850, Article 136850
• Main Authors: Guo, Wan Hui, Zhang, Qing, Wang, Xiao Hu, Yang, Yu Xian, Li, Xiao Lin, Li, Ling Jie, Luo, Hong Qun, Li, Nian Bing
• Format: Article
• Language: English
• Subjects: Carbon; Doping; Electrocatalysts; Electronic structure; Hydrogen evolution reactions; Metal phosphides; Metal-organic frameworks; Nanoparticles; Oxygen evolution reactions; Vanadium doping; Water splitting; Zeolites
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2020.136850

•The ZIF-67 derived V-CoxP@NC NPs are synthesized for the first time.•Introduced vanadium has great contributed to efficient overall water splitting.•V-CoxP@NC NPs show excellent electrocatalytic HER and OER performance.•The catalyst has a potential of 1.54 V at 10 mA cm-2 for overall water splitting. Achieving overall water splitting in the same electrolyte remains a challenge for a cost-effective and durable bifunctional catalyst. Doping foreign element into intrinsic materials is an effective way to enhance the electrocatalytic activity, thus we design a facile method to synthesize a novel vanadium doped mixture of CoP and Co2P nanoparticles encapsulated in zeolitic imidazolate framework-67 (ZIF-67) derived nitrogen doped carbon (V-CoxP@NC NPs) in this work for the first time. Benefiting from the protection of carbon shell and regulation of electronic structure through doping vanadium and phase-mixing CoP and Co2P, the V-CoxP@NC NPs show excellent electrocatalytic performance in both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in 1.0 M KOH. Using V-CoxP@NC NPs to construct overall water splitting (OWS) device, the electrolyzer achieves the current density of 10 mA cm-2 with a small cell voltage of 1.54 V, exhibiting remarkable activity and continuous work for 20 h without obvious fluctuation. MOF-derived V-CoxP@NC NPs exhibit remarkable electrocatalytic water splitting activity, which is attributed to the regulation of electronic structure through introducing vanadium and phase-mixing CoP and Co2P. [Display omitted]