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Luban locks with mortise and tenon structure have structural diversity and architectural stability, and it is extremely challenging to synthesize Luban lock‐like structures at the molecular level. In this work, we report the cocrystallization of two structurally related atom‐precise fcc silver nanoclusters Ag110(SPhF)48(PPh3)12 (Ag110) and Ag14(μ6‐S)(SPhF)12(PPh3)8 (Ag14). It is worth noting that the Ag110 cluster is the first compound to simulate the complex Luban lock structure at the molecular level. Meanwhile, Ag110 is the largest known fcc‐based silver nanocluster, so far, there is no precedent for fcc silver nanocluster with more than 100 silver atoms. DFT calculations show that Ag110 is a 58‐electron superatom with an electronically closed shell1S21P61D102S21F142P61G18. Ag110⋅Ag14 can rapidly catalyze the reduction of 4‐nitrophenol within 4 minutes. In addition, Ag110 presents clear structural evidence to reveal the critical size and mechanism of the transformation of metal core from fcc stacking to quasi‐spherical superatom. This research work provides an important structural model for studying the nucleation mechanism and structural assembly of silver nanoclusters. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Ultrasmall atomically precise thiolate‐protected gold nanoclusters with surface open sites are crucial for practical applications in catalysis. However, there is a lack of systematic studies that unify the kernels‐isomerization, modification of peripheral ligands and electronic effects into one system, as well as their correlation to catalytic performances. In this work, three structurally related Au25nanoclusters with reported star Au25 kernels, Au25‐i‐FTP, Au25‐bi‐FTP, and Au25‐bi‐CHT have been synthesized through two different methods: one‐pot direct reduction and two‐step reduction by using AsPh3 as converter. Their structures and catalytic performance have been comparatively investigated. Au25‐i‐FTP has a classic Au13 core capped by six dimeric RS‐Au‐SR‐Au‐SRs, while Au25‐bi‐FTP and Au25‐bi‐CHT feature typical rod‐shaped biicosahedral geometric kernel. All of the three Au25 clusters were effective catalysts for oxidation of organosilanes, different from conclusions obtained in literature. Especially, the nanorod‐type Au25‐bi‐CHT clusters protected by flexible thiol ligands showed very good catalytic performance in this reaction, the conversion and selectivity were close to 100% within 5 min. The ligand rigidity and electron effects work together to modulate the catalytic properties. The findings inspire us to rethink kernel and ligand effects on catalytic property, and the principle demonstrated here will possibly be widely‐used in high active atom‐precise catalysts modification. [ABSTRACT FROM AUTHOR]

A facile and hard template-assisted spatial confinement strategy was presented to prepare Co SSCs@NG-800-50 catalyst with ultra-high loading of 10.26 wt%, which displays excellent transfer hydrogenation of nitrobenzene with >99% conversion and 96.3% aniline selectivity as well as other nitroaromatics in the presence of HCOOH. [Display omitted] • Co single-site catalysts are fabricated via one-step pyrolysis of DCDA and CoPc mixture. • Co SSCs content reaches 10.26 wt%, which is close to the parent CoPc molecule (10.31 wt%). • SACTEM and XAFS analysis revealed that the Co species are present as CoN 3 structure. • CoN 3 site exhibited superior performance for transfer hydrogenation of nitroaromatics. • DFT calculations disclosed the reaction mechanism of the tandem catalysis. Atomically dispersed non-noble metal single-site catalysts (SSCs) provide a promising approach to meet the catalytic requirements that traditional nanoparticles cannot accomplish. However, they often suffer from formidable challenges of cumbersome route, unmanageable loading, inevitable burial of active site and insufficient stability. Herein, we present a facile and hard template-assisted spatial confinement strategy to prepare Co SSCs embedded in N-doped graphene-like carbon (NG) with ultra-high loading of 10.26 wt%, which is close to the parent CoPc (10.31 wt%). Furthermore, the microstructure, surface area and Co loading in the titled catalysts can be easily manipulated via altering the synthesis parameters. The optimized Co SSCs@NG-800-50 catalyst shows excellent transfer hydrogenation of nitrobenzene with > 99% conversion and 96.3% aniline selectivity as well as good universality for various nitroaromatics in the presence of HCOOH. DFT calculations in combination with elaborate experiments unveil that the active H is firstly generated by the dissociation of C-H bond rather than the recognized O-H bond in HCOOH, then it is used for the hydrogenation of nitroaromatics on CoN 3 site in Co SSCs@NG-800-50 catalyst, revealing the reaction mechanism of the tandem catalysis. This report paves a novel route to design and construct efficient and high-loading non-noble metal SSCs. [ABSTRACT FROM AUTHOR]