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Selective oxidative etching is one of the most effective ways to prepare hollow nanostructures and nanocrystals with specific exposed facets. The mechanism of selective etching in noble metal nanostructures mainly relies on the different reactivity of metal components and the distinct surface energy of multimetallic nanostructures. Recently, phase engineering of nanomaterials (PEN) offers new opportunities for the preparation of unique heterostructures, including heterophase nanostructures. However, the synthesis of hollow multimetallic nanostructures based on crystal‐phase‐selective etching has been rarely studied. Here, a crystal‐phase‐selective etching method is reported to selectively etch the unconventional 4H and 2H phases in the heterophase Au nanostructures. Due to the coating of Pt‐based alloy and the crystal‐phase‐selective etching of 4H‐Au in 4H/face‐centered cubic (fcc) Au nanowires, the well‐defined ladder‐like Au@PtAg nanoframes are prepared. In addition, the 2H‐Au in the fcc‐2H‐fcc Au nanorods and 2H/fcc Au nanosheets can also be selectively etched using the same method. As a proof‐of‐concept application, the ladder‐like Au@PtAg nanoframes are used for the electrocatalytic hydrogen evolution reaction (HER) in acidic media, showing excellent performance that is comparable to the commercial Pt/C catalyst. [ABSTRACT FROM AUTHOR]

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]

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]

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]

Although gapped grain boundaries have often been observed in bulk and nanosized materials, and their crucial roles in some physical and chemical processes have been confirmed, their acquisition at ultrasmall nanoscale presents a significant challenge. To date, they had not been reported in metal nanoparticles smaller than 2 nm owing to the difficulty in characterization and the high instability of grain boundary (GB) atoms. Herein, we have successfully developed a synthesis method for producing a novel chiral nanocluster Au78(TBBT)40 (TBBT=4‐tert‐butylphenylthiolate) with a 26‐atom gapped and rotated GB. This nanocluster was precisely characterized using single‐crystal X‐ray crystallography and mass spectrometry. Additionally, an offset atomic defect linked to the peripheral Au(TBBT)2 staple was found in the structure. Comparing it to similarly face‐centered cubic‐structured Au36(TBBT)24, Au44(TBBT)28, Au52(TBBT)32, Au92(TBBT)44, and ~5 nm nanocrystals, the bridging Au78(TBBT)40 nanocluster exhibited higher catalytic activity in the electroreduction of CO2 to CO. This enhanced activity was explained through density functional theory calculations and X‐ray photoelectron spectroscopy analysis, which highlight the impact of GBs and point defects on the surface properties of metal nanoclusters in balancing intermediate adsorption and product desorption. [ABSTRACT FROM AUTHOR]

Although gapped grain boundaries have often been observed in bulk and nanosized materials, theyhave not been reported in metal nanoparticles smaller than 2 nm owing to the difficulty in characterization and the high instability of grain boundary ( GB) atoms. In their Research Article ( e202410109), Zhikun Wu, Jun Yang, Lingwen Liao et al. report a novel nanocluster with a 26- atom gapped and rotated GB, and demonstrate the effectiveness of manipulating GBs for enhancing the catalytic activity of nanocatalysts. [Extracted from the article]