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For atomically precise metal nanoclusters, distinctive molecular architectures and promising applications are urgently required to be intensively explored. Herein, we have first reported the open shell structure of the [AuAg 26 (S−Adm) 18 S] − nanocluster and its application in the electrochemical reduction of CO 2 . The X-ray crystal structure of the AuAg 26 nanocluster is composed of a AuAg 12 icosahedron kernel and a Ag 14 (SR) 18 S open shell. The shell includes a Ag 6 (SR) 3 S, a Ag 5 (SR) 6 , and three Ag(SR) 3 motifs. It is the first time twisty propeller-like Ag 5 (SR) 6 and trefoil-like Ag 6 (SR) 3 S motifs in metal nanoclusters have been observed. Due to the novel open shell configuration of Ag 14 (SR) 18 S, four triangular facets of the kernel are exposed. The AuAg 26 nanocluster shows excellent catalytic activity in the electrochemical reduction of CO 2 to CO. The Faradaic efficiency of CO is up to 98.4% under −0.97 V. The electrochemical in situ infrared study and DFT calculations demonstrate that the open shell structure of the AuAg 26 nanocluster is beneficial to the forming of intermediate COOH* in the electrochemical reduction of CO 2 to CO.

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We present the cluster-to-cluster transformations among three gold nanoclusters, [Au6(dppp)4]2+ (Au6), [Au8(dppp)4Cl2]2+ (Au8) and [Au11(dppp)5]3+ (Au11). The conversion process follows a rule that states that the transformation of a small cluster to a large cluster is achieved through an oxidation process with an oxidizing agent (H2O2) or with heating, while the conversion of a large cluster to a small one occurs through a reduction process with a reducing agent (NaBH4). All the reactions were monitored using UV-Vis spectroscopy and ESI-MS. This work may provide an alternative approach to the synthesis of novel gold nanoclusters and a further understanding of the structural transformation relationship of gold nanoclusters.

With considerable attention focusing on metal nanoclusters, to explore the relationship of structures and their properties is of prime importance for designing novel functional nanoclusters and promoting their applications. Here we reported two novel alloy nanoclusters, [Pt1Ag24(SR)20]4– and Pt1Ag14(SR)6(PPh3)8 (H-SR: 2-chloro-4-fluorobenzenethiol), determined by X-ray crystallography. Interestingly, the two alloy nanoclusters have the same centered icosahedral Pt1Ag12 kernel, but shell structures are totally different due to the addition of PPh3 in the synthesis. Upon removal of the kernel, the shell of the Pt1Ag24 nanocluster is composed of two unique trefoil-like Ag6(SR)10 motifs, while the Pt1Ag14 nanocluster has six PPh3 and two Ag­(SR)3(PPh3) motifs. Furthermore, fluorescence spectroscopy and ultraviolet–visible absorption spectroscopy (UV–vis) were carried out to investigate the optical properties. The Pt1Ag24 nanocluster has near-infrared photoluminescence at 738 nm, whereas the emission of the Pt1Ag14 nanocluster is at 639 nm, demonstrating a blue shift of 99 nm. The two nanoclusters exhibit distinct optical fingerprints. Furthermore, the predicted partial density of states and UV–vis spectra assignments reveal the relationship of the crystal structures, electronic structures, and optical properties. These findings not only provide a feasible strategy to synthesize functional metal nanoclusters with distinctive structures but also give direct insight into understanding the structure–property correlations at the atomic level.

In this study, we found that phosphine protected [Au(dppp)] and [Au(dppp)Cl] nanoclusters could be reversibly converted under oxidative/reductive conditions. This work not only provides new insights into the relationship between the [Au(dppp)] and [Au(dppp)Cl] nanoclusters, but also offers a novel method for controlling structural evolution of different Au nanoclusters.

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Metal ions have an important impact on the precise control of the synthesis and atomic structural arrangement of noble metal nanoclusters. In this work, the effect of metal ions on the isomer generation of metal nanoclusters is revealed for the first time. Compared with the previous Ag23 nanoclusters with two face‐centered cubic (fcc) unit cells twisting 27°, the Ag23 isomer had a higher symmetry structure with two fcc unit cells almost overlapping. In addition, the UV/Vis absorption spectrum of the isomer showed a slight redshift of approximately 14 nm. The redshift might be because of the modulation of electronic structure, which is derived from fine‐tuned crystal structure. Based on the experimental results, we provide mechanisms to explain the Cu2+ effect on the structural isomer. This work reports a significant finding to tune precisely the crystal structure and understand the mechanism of shape‐controlled synthesis of metal nanoclusters.