Chemical etching manipulated local electronic structure upheaval of graphdiyne for efficient hydrogen evolution. (17th January 2022)

• Record Type: Journal Article
• Authors: Ma, Kaikai; Zhao, Yunqi; Liao, Qingliang; Xiong, Zhaozhao; Li, Xinting; Du, Wenlong; Sun, Yu; Zhang, Zheng; Kang, Zhuo; Zhang, Yue
• Is Part Of: 2D materials. Volume 9:Number 2(2022)
• Publication Date: 2022-01-17
• Subjects: graphdiyne -- electrocatalysts -- hydrogen evolution reaction -- chemical etching -- electronic structure upheaval; Graphene -- Periodicals; Materials science -- Periodicals; Nanostructured materials -- Periodicals; 620.115
• DOI: 10.1088/2053-1583/ac46f9
• Languages: English
• ISSNs: 2053-1583

Abstract

Abstract: Graphdiyne (GDY), featured with unique sp 2, sp-hybridized form and inherent inhomogeneous electron distribution, retains great expectation to be developed into highly efficient electrocatalysts for hydrogen evolution reaction (HER). However, the state-of-the-art GDY-based electrocatalysts still suffer from weak catalytic activity and sluggish reaction kinetics originating from the severe scarcity of in-plane active sites and insufficient electrical conductivity. Targeted at this bottleneck issue, electronic structure regulation, recognized as an extremely precise technical route, is promising to improve HER performances of carbon-based electrocatalysts. Herein, a facile controllable chemical etching strategy is well leveraged to introduce sp 2 -hybridized carbon–oxygen bonds (Csp 2 –O) into GDY for precise manipulation both of its electronic and spatial structures. Experimental results and theoretical calculations coherently manifest that Csp 2 –O introduction into GDY can not only induce its electronic structure upheaval to strengthen surface electron transport capability, but also trigger intensive carbon–oxygen p–p orbital hybridization to enhance the catalytic activity of acetylenic bond sites. As a result, the optimal GDY sample after etching delivers excellent HER performance with an overpotential of only 101 mV at a current density of 10 mA cm −2 and a low Tafel slope of 54 mV dec −1, which surpasses most of reported metal-free based electrocatalysts. This work provides a universal route for precise modulation of inherent electronic structure in GDY, and can be further extended to boost the overall performances of other carbon-based catalysts.