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Gold nanoclusters exhibiting concomitant photothermy (PT) and photoluminescence (PL) under near‐infrared (NIR) light irradiation are rarely reported, and some fundamental issues remain unresolved for such materials. Herein, we concurrently synthesized two novel rod‐shaped Au nanoclusters, Au52(PET)32 and Au66(PET)38 (PET = 2‐phenylethanethiolate), and precisely revealed that their kernels were 4 × 4 × 6 and 5 × 4 × 6 face‐centered cubic (fcc) structures, respectively, based on the numbers of Au layers in the [100], [010], and [001] directions. Following the structural growth mode from Au52(PET)32 to Au66(PET)38, we predicted six more novel nanoclusters. The concurrent synthesis provides rational comparison of the two nanoclusters on the stability, absorption, emission and photothermy, and reveals the aspect ratio‐related properties. An interesting finding is that the two nanoclusters exhibit concomitant PT and PL under 785 nm light irradiation, and the PT and PL are in balance, which was explained by the qualitative evaluation of the radiative and non‐radiative rates. The ligand effects on PT and PL were also investigated. [ABSTRACT FROM AUTHOR]

Atomically precise ~1‐nm Pt nanoparticles (nanoclusters, NCs) with ambient stability are important in fundamental research and exhibit diverse practical applications (catalysis, biomedicine, etc.). However, synthesizing such materials is challenging. Herein, by employing the mixture ligand protecting strategy, we successfully synthesized the largest organic‐ligand‐protected (~1‐nm) Pt23 NCs precisely characterized with mass spectrometry and single‐crystal X‐ray diffraction analyses. Interestingly, natural population analysis and Bader charge calculation indicate an alternate, varying charge ‐layer distribution in the sandwich‐like Pt23 NC kernel. Pt23 NCs can catalyze the oxygen reduction reaction under acidic conditions without requiring calcination and other treatments, and the resulting specific and mass activities without further treatment are sevenfold and eightfold higher than those observed for commercial Pt/C catalysts, respectively. Density functional theory and d‐band center calculations interpret the high activity. Furthermore, Pt23 NCs exhibit a photothermal conversion efficiency of 68.4 % under 532‐nm laser irradiation and can be used at least for six cycles, thus demonstrating great potential for practical applications. [ABSTRACT FROM AUTHOR]

Constructing ambient‐stable, single‐atom‐layered metal‐based materials with atomic precision and understanding their underlying stability mechanisms are challenging. Here, stable single‐atom‐layered nanoclusters of Pd were synthesized and precisely characterized through electrospray ionization mass spectrometry and single‐crystal X‐ray crystallography. A pseudo‐pentalene‐like Pd8 unit was found in the nanocluster, interacting with two syn PPh units through nonmetal‐to‐metal ‐ring coordination. The unexpected coordination, which is distinctly different from the typical organoring‐to‐metal coordination in half‐sandwich‐type organometallic compounds, contributes to the ambient stability of the as‐obtained single‐atom‐layered nanocluster as revealed through theoretical and experimental analyses. Furthermore, quantum chemical calculations revealed dominant electron transition along the horizontal x‐direction of the Pd8 plane, indicating high photothermal conversion efficiency (PCE) of the nanocluster, which was verified by the experimental PCE of 73.3 %. Therefore, this study unveils the birth of a novel type of compound and the finding of the unusual nonmetal‐to‐metal ‐ring coordination and has important implications for future syntheses, structures, properties, and structure–property correlations of single‐atom‐layered metal‐based materials. [ABSTRACT FROM AUTHOR]

Lattice tuning at the ≈1 nm scale is fascinating and challenging; for instance, lattice compression at such a minuscule scale has not been observed. The lattice compression might also bring about some unusual properties, which waits to be verified. Through ligand induction, we herein achieve the lattice compression in a ≈1 nm gold nanocluster for the first time, as detected by the single‐crystal X‐ray crystallography. In a freshly synthesized Au52(CHT)28 (CHT=S‐c−C6H11) nanocluster, the lattice distance of the (110) facet is found to be compressed from 4.51 to 3.58 Å at the near end. However, the lattice distances of the (111) and (100) facets show no change in different positions. The lattice‐compressed nanocluster exhibits superior electrocatalytic activity for the CO2 reduction reaction (CO2RR) compared to that exhibited by the same‐sized Au52(TBBT)32 (TBBT=4‐tert‐butyl‐benzenethiolate) nanocluster and larger Au nanocrystals without lattice variation, indicating that lattice tuning is an efficient method for tailoring the properties of metal nanoclusters. Further theoretical calculations explain the high CO2RR performance of the lattice‐compressed Au52(CHT)28 and provide a correlation between its structure and catalytic activity. [ABSTRACT FROM AUTHOR]

We present a method for atomically precise nanocluster synthesis. As an illustration, we introduced the reducing‐ligand induction combined method and synthesized a novel nanocluster, which was determined to be Au28(SCH2Ph‐tBu)22 with the same number of gold atoms as existing Au28(SR)20 nanoclusters but different ligands (hetero‐composition‐homo‐size). Compared with the latter, the former has distinct properties and structures. In particular, a novel kernel evolution pattern is reported, i.e. the quasi‐linear growth of Au4‐tetrahedron by sharing one vertex and structural features, including a tritetrahedron kernel with two bridging thiolates and two Au6(SCH2Ph‐tBu)6 hexamer chair‐like rings on the kernel surface were also first reported, which endow Au28(SCH2Ph‐tBu)22 with the best photoluminescence quantum yield among hydrophobic thiolated gold nanoclusters so far, probably due to the enhanced charge transfer from the bi‐ring to the kernel via Au−Au bonds. [ABSTRACT FROM AUTHOR]

Can the chemically synthesized nanoparticles act as nanodevices or nanomachines? Herein, we demonstrated this feasibility. A novel nanocluster (ultrasmall nanoparticle) [Au44Cd20(m‐MBT)40][N(C8H17)4]2 (Au44Cd20 in short, m‐MBTH: m‐methylbenzenethiol) obtained via developing a synthesis method has a cannula‐like structure of the outer shell and an internal sleeve, revealed by single‐crystal X‐ray diffraction. Natural population analysis (NPA) charge calculations, charge carrier transport of Au44Cd20 (during which an intra‐nanocluster anti‐galvanic reaction was observed) after unneutral charging using NaBH4 as well as voltammetry proved the capacitor‐like character of Au44Cd20. The subsidiary capacitor‐like character of the outer shell of Au44Cd20 was further probed via NPA charge calculations and electrocatalytic reduction of CO2 to CO. Thus, this study predicts a new era of engineering metal nanoparticles for realizing atomically precise ultrasmall nanodevices and nanomachines. [ABSTRACT FROM AUTHOR]

This article, published in Angewandte Chemie, discusses the discovery of the largest organic-ligand-protected Pt nanoclusters with atomic precision. The researchers found that these Pt23 nanoclusters exhibited superior catalytic activity for the oxygen reduction reaction under acidic conditions compared to commercial Pt/C catalysts, without the need for additional treatments. Additionally, the nanoclusters demonstrated excellent photothermal conversion efficiency, suggesting potential applications in various fields. The article also briefly mentions other research topics, including the synthesis of sulfur-containing polymers and the development of naphthalene diimide anolytes for neutral flow batteries. [Extracted from the article]

Constructing ambient-stable, single-atom-layered metal-based materials with atomic precision and understanding their underlying stability mechanisms are challenging. Here, stable single-atom-layered nanoclusters of Pd were synthesized and precisely characterized through electrospray ionization mass spectrometry and single-crystal X-ray crystallography. A pseudo-pentalene-like Pd 8 unit was found in the nanocluster, interacting with two syn PPh units through nonmetal-to-metal -ring coordination. The unexpected coordination, which is distinctly different from the typical organoring-to-metal coordination in half-sandwich-type organometallic compounds, contributes to the ambient stability of the as-obtained single-atom-layered nanocluster as revealed through theoretical and experimental analyses. Furthermore, quantum chemical calculations revealed dominant electron transition along the horizontal x-direction of the Pd 8 plane, indicating high photothermal conversion efficiency (PCE) of the nanocluster, which was verified by the experimental PCE of 73.3 %. Therefore, this study unveils the birth of a novel type of compound and the finding of the unusual nonmetal-to-metal -ring coordination and has important implications for future syntheses, structures, properties, and structure-property correlations of single-atom-layered metal-based materials., (© 2023 Wiley-VCH GmbH.)

Metal nanoclusters have recently attracted extensive interest from the scientific community. However, unlike carbon-based materials and metal nanocrystals, they rarely exhibit a sheet kernel structure, probably owing to the instability caused by the high exposure of metal atoms (particularly in the relatively less noble Ag or Cu nanoclusters) in such a structure. Herein, we synthesized a novel AgCu nanocluster with a sandwich-like kernel (diameter≈0.9 nm and length≈0.25 nm) by introducing the furfuryl mercaptan ligand (FUR) and the alloying strategy. Interestingly, the kernel consists of a centered silver atom and two planar Ag 10 pentacle units with completely mirrored symmetry after a rotation of 36 degrees. The two Ag 10 pentacles and some extended structures show an unreported golden ratio geometry, and the two inner five-membered rings and the centered Ag atom form an unanticipated full-metal ferrocene-like structure. The featured kernel structure causes the dominant radial direction transition of excitation electrons, as determined via time-dependent density functional theory calculations, which affords the protruding absorption at 612 nm and contributes to the promising photothermal conversion efficiency of 67.6 % of the as-obtained nanocluster, having important implications for structure-property correlation and the development of nanocluser-based photothermal materials., (© 2023 Wiley-VCH GmbH.)

We present a method for atomically precise nanocluster synthesis. As an illustration, we introduced the reducing-ligand induction combined method and synthesized a novel nanocluster, which was determined to be Au 28 (SCH 2 Ph- t Bu) 22 with the same number of gold atoms as existing Au 28 (SR) 20 nanoclusters but different ligands (hetero-composition-homo-size). Compared with the latter, the former has distinct properties and structures. In particular, a novel kernel evolution pattern is reported, i.e., the quasi-linear growth of Au 4 -tetrahedron by sharing one vertex and structural features, including a tritetrahedron kernel with two bridging thiolates and two Au 6 (SCH 2 Ph- t Bu) 6 hexamer chair-like rings on the kernel surface were also first reported, which endow Au 28 (SCH 2 Ph- t Bu) 22 with the best photoluminescence quantum yield among hydrophobic thiolated gold nanoclusters so far, probably due to the enhanced charge transfer from the bi-ring to the kernel via Au-Au bonds., (© 2021 Wiley-VCH GmbH.)

Removing or adding kernel atoms of metal nanoclusters (NCs) without leaving a trace is a substantial challenge because the kernel atoms are inside and covered by the outer staples. However, such kernel tuning is very important for improving the properties and acquiring an in-depth understanding of the kernel-property correlation. Photoluminescence (PL) is one of the most intriguing characteristics of metal NCs but has not been well understood until now. Inspired by these challenges/questions, we conducted this study and, for the first time, achieved the traceless removal of two kernel atoms in a gold nanocluster by applying a simple thermal treatment and revealed its impact on PL. Further, we demonstrated that the kernel Au-Au bond length can be an indicator for a comparison of the PL or kernel charge state between nanoclusters with similar kernel structures and sizes., (© 2021 Wiley-VCH GmbH.)

Homology is well known in organic chemistry; however, it has not yet been reported in nanochemistry. Herein, we introduce the concept of kernel homology to describe the phenomenon of metal nanoclusters sharing the same "functional group" in kernels with some similar properties. To illustrate this point, we synthesized two novel gold nanoclusters, Au 44 (TBBT) 26 and Au 48 (TBBT) 28 (TBBTH=4-tert-butylbenzenethiol), and solved their total structures by X-ray crystallography, which reveals that they have the same Au 23 bi-icosahedron capped with a similar bottom cap (Au 6 and Au 8 , respectively) in the kernels. The two novel gold nanoclusters, together with the existing Au 38 (PET) 24 nanocluster (PETH=phenylethanethiol), have the same "functional group"-Au 23 -in their kernels and have some similar properties (e.g., electrochemical properties); therefore, they are comparable to the homologues in organic chemistry., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)