文献类型：期刊文献

英文题名：Nitrogen-Stabilized Low-Valent Ni Motifs for Efficient CO2 Electrocatalysis

作者：Wen, Chun Fang[1];Mao, Fangxin[1];Liu, Yuanwei[1];Zhang, Xin Yu[1];Fu, Huai Qin[1];Zheng, Li Rong[2];Liu, Peng Fei[1];Yang, Hua Gui[1]

机构：[1]East China Univ Sci & Technol, Sch Mat Sci & Engn, Shanghai Engn Res Ctr Hierarch Nanomat, Key Lab Ultrafine Mat,Minist Educ, 130 Meilong Rd, Shanghai 200237, Peoples R China;[2]Chinese Acad Sci, Inst High Energy Phys, Beijing Synchrotron Radiat Facil, Beijing 100049, Peoples R China

年份：2020

卷号：10

期号：2

起止页码：1086

外文期刊名：ACS CATALYSIS

收录：;EI(收录号：20200208019682);WOS:【SCI-EXPANDED(收录号:WOS:000508466700013)】；

基金：This work was financially supported by the National Natural Science Funds for Distinguished Young Scholar (51725201), International (Regional) Cooperation and Exchange Projects of the National Natural Science Foundation of China (51920105003), Innovation Program of Shanghai Municipal Education Commission (E00014), National Natural Science Foundation of China (21573068 and 51902105), Shanghai Engineering Research Center of Hierarchical Nanomaterials (18DZ2252400), Shanghai Sailing Program (19YF1411600), and China Postdoctoral Science Foundation Funded Project (2018M641938).

语种：英文

外文关键词：CO2 reduction reaction; nitrogen-modified Ni catalyst; operando XAFS; single-atom catalysis; electrocatalysis

摘要：Single-atom catalysts have found considerable applications in the field of electrochemical CO2 reduction reaction (CO2RR) due to their unique coordination environments. However, during the preparation of single-atom catalysts, some metal nanoparticles (NPs) are inevitably generated, which suffer from low selectivity in CO2RR. In this regard, complex postprocessing solution treatments are usually conducted to remove metal NPs using acid. Herein, we fabricated Ni(NC)-based catalysts composed of single Ni atoms and Ni NPs, both of which feature local Ni-N coordination via a simple Ni-metal organic framework (MOF)-assisted strategy. Based on X-ray photoelectron spectroscopy (XPS) and X-ray absorption fine structure (XAFS) spectroscopy measurements, nitrogen species in N-doped carbon have been demonstrated to be coordinated with surface nickel species to form Ni-N motifs, which makes Ni at a low-valent state for efficient CO2RR. Consequently, the catalyst exhibited high performances toward CO2RR with CO Faradic efficiencies (FECO) maintained over 90% from -0.65 to -0.90 V vs reversible hydrogen electrode (RHE). More importantly, the FECO of 99% could be obtained at a considerable current density (j) of -160 mA cm(-2) in a flow cell configuration. These findings suggest that regulating the surface environment of Ni species can activate the original inert reaction sites into active reaction sites, providing a promising avenue to design high-performance electrocatalysts for CO2RR.