Graphdiyne-anchored ultrafine NiFe hydroxide nanodots electrocatalyst for water oxidation with high mass activity and superior durability. (November 2020)

• Record Type: Journal Article
• Authors: Lv, Yan; Wu, Xueyan; Jia, Wei; Guo, Jixi; Zhang, Hongbo; Liu, Huibiao; Jia, Dianzeng; Tong, Fenglian
• Is Part Of: Carbon. Volume 169(2020)
• Page Start: 45
• Page End: 54
• Publication Date: 2020-11
• Subjects: Graphdiyne -- NiFe-LDH -- Nanodots -- Electrocatalyst -- Water oxidation; Carbon -- Periodicals; Carbone -- Périodiques; Koolstof; Toepassingen; Electronic journals; 546.681
• DOI: 10.1016/j.carbon.2020.07.048
• Languages: English
• ISSNs: 0008-6223

Abstract

Abstract: Structural and interface engineering enable the optimization of electrocatalysts in terms of both activity and durability. Herein, the three-dimensional (3D) architecture graphdiyne nanowall (GDY) serving as scaffolds anchor metal cations to form the NiFe layered double hydroxide (LDH) nanodots/graphdiyne (NiFe ND/GDY) heterojunction electrocatalysts for water oxidation in alkaline solution. After tuning the loading amount of NiFe-LDH carefully, the NiFe ND displays ultrasmall nanometer size of 2.7 nm and intimate interfacial coupling with GDY. Owing to the optimized 0D/3D structure, strong interfacial forces and the unique properties of GDY, the resulting NiFe ND/GDY requires an overpotential of only 252 mV to deliver current density of 10 mA cm −2 and shows favorable kinetics with a small Tafel slope of 39.70 mV dec −1 . Notably, the mass activity of NiFe ND/GDY heterojunction is 70 times higher than that of the commercial RuO2 (631 A g −1 vs. 9 A g −1 to RuO2, at η = 300 mV), and it exhibits a superior long-term stability (only 10% degradation during continuous electrolysis of 100 h). This work indicates that GDY can serve as a promising substrate to anchor the ultrafine nanoparticle catalysts for water oxidation or beyond. Graphical abstract: Graphdiyne anchored NiFe-LDH nanodots (NiFe ND/GDY) electrocatalyst for water oxidation are synthesized. NiFe ND shows ultrafine size of 2.7 nm and intimate interfacial coupling with GDY. GDY substrate enhances the charge/mass transport and high accessible active surface area. The electrocatalyst exhibits a mass activity 70 times higher than RuO2 at η = 300 mV, and superior durability of over 100 h at the current density of 20 mA cm −2 . Image 1