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The reduction of alkynyl‐silver and phosphine‐silver precursors with a weak reducing reagent Ph2SiH2 led to the formation of a novel silver nanocluster [Ag93(PPh3)6(C≡CR)50]3+ (R=4‐CH3OC6H4), which is the largest structurally characterized cluster of clusters. This disc‐shaped cluster has a Ag69 kernel consisting of a bicapped hexagonal prismatic Ag15 unit wrapped by six Ino decahedra through edge‐sharing. This is the first time that Ino decahedra are used as a building block to assemble a cluster of clusters. Moreover, the central silver atom has a coordination number of 14, which is the highest in metal nanoclusters. This work provides a diverse metal packing pattern in metal nanoclusters, which is helpful for understanding metal cluster assembling mechanisms. [ABSTRACT FROM AUTHOR]

Atomically precise gold nanoclusters provide great opportunities to explore the relationship between the structure and properties of nanogold catalysts. A nanocluster consists of a metal core and a surface ligand shell, and both the core and shell have significant effects on the catalytic properties. Thanks to their precise structures, the active metal site of the clusters can be readily identified and the effects of ligands on catalysis can be disclosed. In this Minireview, we summarize recent advances in catalytic research of gold nanoclusters, emphasizing four strategies for constructing open metal sites, including by post‐treatment, the bulky ligands strategy, the surface geometric mismatch method, and heteroatom doping procedures. We also discuss the effects of ligands on the catalytic activity, selectivity, and stability of gold cluster catalysts. Finally, we present future challenges relating to gold cluster catalysis. [ABSTRACT FROM AUTHOR]

Anions have been used to regulate the structures and luminescence of heterometallic clusters. Introducing ClO4− into orange‐emissive, butterfly‐like [(C)(Au‐PPhpy2)6Ag4](BF4)6 (1, PPhpy2=bis(2‐pyridyl)phenylphosphine) leads to the formation of red‐emissive [(C)(Au‐PPhpy2)6Ag5(ClO4)3](ClO4)4 (2) with a novel trigonal bipyramidal structure; employing PhCO2− gives yellow‐emissive, hexagram‐like [(C)(Au‐PPhpy2)6Ag6(PhCO2)3](BF4)5 (3). Notably, 1 exhibits weak luminescence in CH2Cl2/CH3OH=1 : 1 (v : v) with a quantum yield (QY) of 0.05, whereas it was dramatically increased to 0.49 and 0.83 for 2 and 3, respectively. Theoretical calculation confirms that the involvement of anions in the electronic structures is responsible for the shifts of emission. The high QYs of 2 and 3 are attributed to the protection provided by ligands and anions. This work demonstrates that anions may serve as an extra designable factor beyond just counterions for functional metal clusters. [ABSTRACT FROM AUTHOR]

Acetelyenediide (C22−) species have been encapsulated in bimetallic and trimetallic clusters: [(AuL)6Ag7(C≡C)3](BF4)7 (2) and [(AuL)6AgCu6(C≡C)3](BF4)7 (3), L=phenylbis(2‐pyridyl)phosphine (PPhpy2). Single‐crystal X‐ray diffraction analysis revealed that they are isostructural and six silver atoms in 2 are replaced with copper in 3. Both clusters have a trefoil skeleton, which can be viewed as three trigonal bipyramidal (LAu‐C≡C‐AuL)M2Ag (M=Ag/Cu) motifs sharing a common silver atom. TDDFT calculations showed Cu‐doping significantly increases the energy level of (C2‐Cu)‐involved occupied orbital, thus inducing interesting transition coupling of dual‐emission at low temperature. This work not only provides a strategy for constructing heterometallic clusters, but also shows the prospect for pursuing novel thermochromic luminescent materials by incorporating multi‐congeneric metal components. [ABSTRACT FROM AUTHOR]

[Display omitted] • First Example of a molecular cage being used in the overall water splitting. • Remote metal binding site of the cage determines the reconstruction degree. • Two-electrode system has an overpotential of 320 mV and up to 100 h duration. Developing porous materials with superior performance and exceptional durability for efficient overall water-splitting, poses a highly demanding and exceedingly challenging task. In particular, elucidating the correlation between the structure of catalysts and their catalytic activities is of paramount importance. Herein, we present two porous coordination cages (PCCs) featuring redox-active metal clusters and adjustable secondary metal ion binding sites. PCCs undergo self-reconstruction during redox electrochemistry and yield a highly active CoOOH@PCC species. More significantly, the introduction of secondary metals greatly facilitates the reconstruction of PCCs, especially for ones with remote metal sites (sulfate moieties). The Fe3+-doped PCC a exhibits higher degree of reconstruction, and the reconstructed CoOOH@a achieved the optimal catalytic performance towards the OER; Remarkably, the OER performance of CoOOH@a was boosted to a low overpotential of 225 mV at 10 mA cm−2 following reconstruction. In addition, Pt4+ promotes the excellent performance of PCC a in HER. These findings provide fundamental insights into the "structure–property-relationship" of OER/HER catalysts, highlighting PCC as a promising candidate in flexible electrocatalysts. [ABSTRACT FROM AUTHOR]