Asymmetric Exchange Interaction Induces Highly Efficient Alkaline Hydrogen Evolution in RhFe Bimetallene. Issue 42 (18th September 2022)

• Record Type: Journal Article
• Authors: Yan, Kun; Wei, Tingting; Ren, Hengdong; Wu, Jianghua; Pan, Xiaoqing; Xu, Xiaobing; Liu, Lizhe; Wu, Xinglong
• Is Part Of: Small. Volume 18:Issue 42(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-09-18
• Subjects: asymmetric exchange interaction -- d band center -- electron hopping -- hydrogen adsorption energy -- hydrogen evolution reaction -- RhFe bimetallene; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.202204456
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract: An RhFe bimetallene with Fe atoms doped into Rh host for efficient hydrogen evolution reaction (HER), is constructed. When two doped Fe atoms occupy neighboring asymmetric spatial positions, their asymmetric exchange interaction drives electron hopping between the dxy orbital of a Fe atom and the dz 2 orbital of its neighboring Fe atom to push the d band center closer to the Fermi level as a result of electronic state reconstruction. The designed bimetallene with thickness of 0.77 nm (5 atomic layers), possesses excellent HER performance. The low overpotentials of 24.4 and 34.6 mV are achieved at the 10 and 100 mA cm −2 current densities in 1 m KOH solution, respectively. An ultra‐low Tafel slope of 8.9 mV dec −1 shows that this kind of RhFe bimetallene is of an ultrafast kinetic process. This work provides a strategy for designing HER catalysts with double metal composites. Abstract : In RhFe bimetallene, asymmetric exchange interaction drives electron hopping from the dxy orbital of an Fe atom to the dz 2 orbital of its neighboring Fe atom, and then pushes the d band center of the surface Fe atom closer to the Fermi level and achieves an extremely small hydrogen adsorption energy of 0.038 eV for excellent hydrogen evolution reaction performance.