Identifying the Real Chemistry of the Synthesis and Reversible Transformation of AuCd Bimetallic Clusters

Huixin Xiang; Hao Yan; Jiaohu Liu; Ranran Cheng; Cong-Qiao Xu; Jun Li; Chuanhao Yao

doi:10.1021/jacs.2c05053

Identifying the Real Chemistry of the Synthesis and Reversible Transformation of AuCd Bimetallic Clusters

J Am Chem Soc. 2022 Aug 10;144(31):14248-14257. doi: 10.1021/jacs.2c05053. Epub 2022 Jun 23.

Authors

Huixin Xiang¹, Hao Yan¹, Jiaohu Liu¹, Ranran Cheng¹, Cong-Qiao Xu², Jun Li^{2

3}, Chuanhao Yao¹

Affiliations

¹ Frontiers Science Center for Flexible Electronics, Institute of Flexible Electronics (IFE) and Ningbo Institute of NPU, Northwestern Polytechnical University, 127 West Youyi Road, Xi'an 710072, China.
² Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China.
³ Department of Chemistry, Tsinghua University, Beijing 100084, China.

PMID: 35737965
DOI: 10.1021/jacs.2c05053

Abstract

The capability of precisely constructing bimetallic clusters with atomic accuracy provides exciting opportunities for establishing their structure-property correlations. However, the chemistry (the charge state of precursors, the property of ligands, the amount of dopant, and so forth) dictating the fabrication of clusters with atomic-level control has been a long-standing challenge. Herein, based on the well-defined Au₂₅(SR)₁₈ cluster (SR = thiolates), we have systematically investigated the factors of steric hindrance and electronic effect of ligands, the charge state of Au₂₅(SR)₁₈, and the amount of dopant that may determine the structure of AuCd clusters. It is revealed that [Au₁₉Cd₃(SR)₁₈]^- can be obtained when a ligand of smaller steric hindrance is used, while Au₂₄Cd(SR)₁₈ is attained when a larger steric hindrance ligand is used. In addition, negatively charged [Au₂₅(SR)₁₈]^- is apt to form [Au₁₉Cd₃(SR)₁₈]^- during Cd doping, while Au₂₄Cd(SR)₁₈ is produced when neutral Au₂₅(SR)₁₈ is used as a precursor. Intriguingly, the reversible transformation between [Au₁₉Cd₃(SR)₁₈]^- and Au₂₄Cd(SR)₁₈ is feasible by subtly manipulating ligands with different steric hindrances. Most importantly, by introducing the excess amount of dopant, a novel bimetallic cluster, Au₄Cd₄(SR)₁₂ is successfully fabricated and its total structure is fully determined. The electronic structures and the chirality of Au₄Cd₄(SR)₁₂ have been elucidated by density functional theory (DFT) calculations. Au₄Cd₄(SR)₁₂ reported herein represents the smallest AuCd bimetallic cluster with chirality.