Synergistic Effect of Metal Doping and Tethered Ligand Promoted High-Selectivity Conversion of CO_(2)to C_(2)Oxygenates at Ultra-Low Potential  

作　　者：Xiaowan Bai Li Shi Qiang Li Chongyi Ling Yixin Ouyang Shiyan Wang Jinlan Wang 

机构地区：[1]School of Physics,Southeast University,Nanjing 211189,China

出　　处：《Energy & Environmental Materials》2022年第3期892-898,共7页能源与环境材料（英文）

基　　金：supported by the National Natural Science Foundation of China(Grant No.22033002,21525311,21773027);the Scientific Research Foundation of Graduate School of Southeast University(YBPY1920);the China Postdoctoral Science Foundation(Grant No.2020M681450);the China Scholarship Council(CSC,201906090150)。

摘　　要：Effectively controlling the selectivity of C_(2) oxygenates is desirable for electrocatalytic CO_(2) reduction.Copper catalyst has been considered as the most potential for reducing CO_(2) to C_(2) products,but it still suffers from low C_(2) selectivity,high overpotential,and competitive hydrogen evolution reaction(HER).Here,we propose a design strategy to introduce a second metal that weakly binds to H and a functional ligand that provides hydrogen bonds and protons to achieve high selectivity of C_(2)oxygenates and effective suppression of HER on the Cu(100)surface simultaneously.Seven metals and eleven ligands are screened using first-principles calculations,which shows that Sn is the most efficient for inhibiting HER and cysteamine(CYS)ligand is the most significant in reducing the limiting potential of^(*)CO hydrogenation to^(*)CHO.In the post C-C coupling steps,a so-called“pulling effect”that transfers H in the CYS ligand as a viable proton donor to the C_(2)intermediate to form an H bond,can further stabilize the OH group and facilitate the selection of C_(2)products toward oxygenates.Therefore,this heterogeneous electrocatalyst can effectively reduce CO_(2)to ethanol and ethylene glycol with an ultra-low limiting potential of-0.43 V.This study provides a new strategy for effectively improving the selectivity of C_(2)oxygenates and inhibiting HER to achieve advanced electrocatalytic CO_(2)reduction.

关 键 词：metal doping hydrogen-bonding ligand density functional theory electrochemical CO_(2)reduction C_(2)oxygenates selectivity 

分 类 号：TQ207[化学工程—有机化工] O643.36[理学—物理化学] X701[理学—化学]