原位构建具有铋合金纳米片的三维导电核壳纳米网络和电子结构用于高效电催化CO_(2)还原  

In situ engineering 3D conductive core-shell nano-networks and electronic structure of bismuth alloy nanosheets for efficient electrocatalytic CO_(2)reduction

作　　者：胡延杰 王心英 张嘉城 张家明 张杨涛 梁嘉文 李运勇 Yanjie Hu;Xinying Wang;Jiacheng Zhang;Jiaming Zhang;Yangtao Zhang;Jiawen Liang;Yunyong Li(School of Materials and Energy,Guangdong University of Technology,Guangzhou 510006,China)

机构地区：[1]School of Materials and Energy,Guangdong University of Technology,Guangzhou 510006,China

出　　处：《Science China Materials》2023年第6期2266-2273,共8页中国科学（材料科学（英文版）

基　　金：supported by the National Natural Science Foundation of China(51972066);the Natural Science Foundation of Guangdong Province of China(2021A1515011718);Guangdong Province Universities and Colleges Pearl River Scholar Funded Scheme(2017)。

摘　　要：由于CO_(2)传质的限制,在H型电池中,具有高法拉第效率(>90%)和大电流密度(>150 mA cm^(-2))的电催化CO_(2)还原(CO_(2)RR)制备HCOOH燃料的过程非常具有挑战性.在本文中,我们报道了一种在泡沫Cu上原位构建具有三维(3D)多孔网络核壳纳米线结构的优异CO_(2)RR电催化剂.核壳结构由Cu纳米线核和Sb-Bi合金壳组成(Cu@Sb_(x)Bi_(y)NWs/Cu).制备的Cu@Sb_(x)Bi_(y)NWs/Cu具有171.3mA cm^(-2)的高电流密度以及92%的HCOOH法拉第效率,就电流密度而言优于几乎所有报道的铋基催化剂.理论研究表明,Sb的引入使Bi的电子态提高到接近费米能级,与纯Bi表面相比,^(*)OCHO中间体更易吸附在Sb-Bi界面上,从而加速CO_(2)还原.此外,Sb_(0.1)Bi_(1)与纯Bi相比具有更强的键能,这有利于催化剂在反应过程中的稳定性.Sb_(0.1)Bi_(1)合金和3D导电核壳纳米网络的形成更有利于快速电子转移,并在反应过程中暴露出更多的活性位点,从而获得更好的催化活性.这项工作为设计用于能量转换的高活性铋基催化剂提供了理论依据.The electrocatalytic carbon dioxide reduction reaction(CO_(2)RR)to obtain valuable formic acid(HCOOH)with high Faradaic efficiency(90%)and large current density(150 mA cm^(-2))in H-type cells is extremely challenging due to the carbon dioxide(CO_(2))mass transfer limitation.This study reports an excellent electrocatalyst for the CO_(2RR)based on the in-situ construction of three-dimensional(3D)porous networked core-shell nanowire structures on copper(Cu)foam.The core-shell structure comprises a Cu nanowire(NW)core and an antimony-bismuth(Sb-Bi)alloy shell(Cu@Sb_xBi_(y)NWs/Cu).The as-prepared Cu@Sb_xBi_(y)NWs/Cu exhibits a high current density of 171.3 mA cm^(-2)along with 92%Faradaic efficiency of HCOOH(FEHCOOH),which is superior to most reported studies in terms of high current density.Theoretical research has shown that introducing Sb upshifts the electron states of Bi close to the Fermi level,allowing more advantageous adsorption of the~*OCHO intermediate onto SbBi interfaces than Bi surfaces,thereby accelerating the CO_(2)RR.Furthermore,Sb_(0.1)Bi_(1)has stronger bond energy than pure Bi,favoring the stability of the catalyst during the reaction.Additionally,the formation of the Sb_(0.1)Bi_(1)alloy and 3D conductive core-shell nano-networks is more conducive to fast electron transfer and exposure of more active sites in the reaction process,obtaining better catalytic activity.This study provides valuable insights into the design of highly active Bibased catalysts for energy conversion.

关 键 词：电催化 电子转移 费米能级 电子态 大电流密度 核壳 能量转换 纳米网络 

分 类 号：TQ426[化学工程] TB383.1[一般工业技术—材料科学与工程] X701[环境科学与工程—环境工程]