摘要
Designing active,robust and cost-effective catalysts for the nitrogen reduction reaction(NRR) is of paramount significance for sustainable electrochemical NH3 synthesis.Transition-metal diborides(TMB_2)have been recently theoretically predicted to be a new class of potential NRR catalysts,but direct experimental evidence is still lacking.Herein,we present the first experimental demonstration that amorphous FeB_2 porous nanosheets(a-FeB_2 PNSs) could be a highly efficient NRR catalyst,which exhibited an NH3 yield of 39.8 μg h^(-1) mg^(-1)(-0.3 V) and a Faradaic efficiency of 16.7%(-0.2 V),significantly outperforming their crystalline counterpart and most of existing NRR catalysts.First-principle calculations unveiled that the amorphization could induce the upraised d-band center of a-FeB_2 to boost d-2π~* coupling between the active Fe site and ~*N_2 H intermediate,resulting in enhanced ~*N_2 H stabilization and reduced reaction barrier.Out study may facilitate the development and understanding of earth-abundant TMB_2-based catalysts for electrocatalytic N_2 fixation.
基金
supported by the National Natural Science Foundation of China (51761024)
the CAS ‘‘Light of West China” Program, ‘‘Feitian Scholar” Program of Gansu Province
the Foundation of A Hundred Youth Talents Training Program of Lanzhou Jiaotong University。
