物理化学学报2023，Vol.39Issue(12)：79-86,8.DOI:10.3866/PKU.WHXB202212064
组合掺杂引入新型、多种镉配位方式增强金纳米团簇的电催化性能
Introducing Novel,Multiple Cd Coordination Modes into Gold Nanoclusters by Combined Doping for Enhancing Electrocatalytic Performance
摘要
Abstract
In recent years,gold nanoclusters have been widely used in catalysis,and alloying has become one of the most important methods for improving the catalytic performance of gold nanoclusters.As for the electrocatalytic reduction of CO2(CO2RR),although many gold nanoclusters show fairly good Faraday efficiencies through Cd-doping,they still exhibit low current density.Furthermore,as an increasing number of Au-Cd alloy nanoclusters are reported,there is a growing interest in understanding the correlation between Cd coordination and catalysis performance.In most cases,Cd atoms are typically doped in the outer staples and connect with Au atoms through S coordinations.Are there any other unreported Cd coordination modes?Can novel or numerous Cd coordination modes be introduced into gold nanoclusters to increase the current density in the CO2RR?This study investigates these questions.Inspired by our previous work on surface sulfur doping,we employed a combined doping(S+Cd doping)strategy,developed a two-step synthesis method,and successfully synthesized a novel Au-Cd nanocluster-Au41Cd6S2(SCH2Ph)33.Precise formula and structure were determined by electrospray ionization mass spectrometry(ESI-MS),thermalgravimetric analysis(TGA),X-ray photoelectron spectroscopy(XPS),and single-crystal X-ray crystallography(SCXC).SCXC shows that the nanocluster contains a biicosahedral Au23 kernel,and all the Cd atoms are doped in the outer staples,providing a variety of coordination environments for Cd atoms.In addition to two common Au3(SR)4 trimers in the outer staples,two unusual Au5Cd2(SR)9S long staples were discovered cross-covering the top of the kernel,and a(S-Au-S)2(CdS-S-CdS)tetramer staple with two Cd atoms directly linked through S was also discovered for the first time.This alloy cluster shows robust stability in both high-temperature and oxidation environments.Compared with the"homo-kernel-hetero-staples"nanocluster Au38(SCH2Ph)24,Au41Cd6S2(SCH2Ph)33 exhibits distinct UV-Vis/NIR absorption and differential pulse voltammetry(DPV)results,indicating that the differences in the outer staples have a significant effect on the optical and electronic properties of gold nanoclusters.When used as an electrocatalyst,the Au41Cd6S2(SCH2Ph)33 exhibits a higher Faradaic efficiency for the CO2RR(99.3％at-0.7 V)and a higher CO partial current density(120 mA·cm-2 at-0.9 V)than Au38(SCH2Ph)24,providing an ideal platform for investigating the roles of different Cd coordination modes in outer staples on CO2RR.DFT calculations interpret the experimental finding that Cd doping improves the catalytic performance and reveal that the Cd-Cd site is the most active site and the Au-Cd site furthest away from the kernel is the best-performing catalytic site given the consideration of both selectivity and activity.This work introduces a novel strategy to enhance the catalytic performance of gold nanoclusters,having important implications for future research on the syntheses and structural properties of metal nanoclusters,and is expected to inspire more work in related areas.关键词
金属纳米团簇/组合掺杂/镉配位方式/构效关系/电催化CO2还原Key words
Metal Nanocluster/Combined doping/Cd-coordination mode/Structure-property correlation/Electrocatalytic reduction of CO2分类
化学引用本文复制引用
刘真,孟祥福,古万苗,查珺,闫楠,尤青,夏楠,王辉,伍志鲲..组合掺杂引入新型、多种镉配位方式增强金纳米团簇的电催化性能[J].物理化学学报,2023,39(12):79-86,8.基金项目
The project was supported by the National Natural Science Foundation of China(21829501,21925303,22171267,22171268,21771186,21222301,21171170,21528303),Anhui Provincial Natural Science Foundation(2008085MB31,2108085MB56),CASHIPS Director's Fund(BJPY2019A02),Collaborative Innovation Program of Hefei Science Center,CAS(2020HSC-CIP005,2022HSC-CIP018).国家自然科学基金(21829501,21925303,22171267,22171268,21771186,21222301,21171170,21528303),安徽省自然科学基金(2008085MB31,2108085MB56),中国科学院合肥研究院院长基金(BJPY2019A02)及中国科学院合肥科学中心协同创新项目(2020HSC-CIP005,2022HSC-CIP018)资助 （21829501,21925303,22171267,22171268,21771186,21222301,21171170,21528303）
