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In the present study, we illustrated a facile fabrication of large scale ultra‐thin silver sulfide (Ag2S) nanowires (NWs) and its promising application in hydrogen evolution reaction (HER). Ultra‐thin and highly uniform Ag2S nanostructures were fabricated from single‐source precursor [(PPh3)2AgS2P(OiPr)2], and characterized by utilizing various structural and imaging techniques. Large‐scale monodispersed ultra‐thin single‐crystalline Ag2S nanowires were generated via n‐decylboronic acid induced thermal decomposition of the single precursor in the presence of octadecyl amine and oleyl amine mixture under anaerobic conditions. We explored the catalytic activities of Ag2S nanowires for HER which showed an overpotential of−88 mV at 10 mA/cm2 and the corresponding Tafel slope was found to be 52 mV dec−1.

The dichalcogenide ligated molecules in catalysis to produce molecular hydrogen through electroreduction of water are rarely explored. Here, a series of heterometallic [Ag 4 (S 2 PFc(OR) 4 ] [where Fc = Fe(η 5 -C 5 H 4 )(η 5 -C 5 H 5 ), R = Me, 1; Et, 2; n Pr, 3; iso Amyl, 4] clusters were synthesized and characterized by IR, absorption spectroscopy, NMR ( 1 H, 31 P), and electrospray ionization mass spectrometry. The molecular structures of 1, 2, and 3 clusters were established by single-crystal X-ray crystallographic analysis. The structural elucidation shows that each triangular face of a tetrahedral silver(I) core is capped by a ferrocenyl dithiophosphonate ligand in a trimetallic triconnective (η 3 ; μ 2 , μ 1 ) pattern. A comparative electrocatalytic hydrogen evolution reaction of 1−5 (R = i Pr, 5) was studied in order to demonstrate the potential of these clusters in water splitting activity. The experimental results reveal that catalytic performance decreases with increases in the length of the carbon chain and branching within the alkoxy (-OR) group of these clusters. Catalytic durability was found effective even after 8 h of a chronoamperometric stability test along with 1500 cycles of linear sweep voltammetry performance, and only 15 mV overpotential was increased at 5 mA/cm 2 current density for cluster 1. A catalytic mechanism was proposed by applying density functional theory (DFT) on clusters 1 and 2 as a representative. Here, a μ 1 coordinated S-site between Ag 4 core and ligand was found a reaction center. The experimental results are also in good accordance with the DFT analysis.

The preparation of high-nuclearity silver nanoclusters in quantitative yield remains exclusive and their potential applications in the catalysis of organic reactions are still undeveloped. Here, we have synthesized a quantum dot (QD)-based catalyst, [Ag62S13(SBu t )32]­(PF6)4 (denoted as Ag62S12-S) in excellent yield that enables the direct synthesis of pharmaceutically precious 3,4-dihydroquinolinone in 92% via a decarboxylative radical cascade reaction of cinnamamide with α-oxocarboxylic acid under mild reaction conditions. In comparison, a superatom [Ag62S12(SBu t )32]­(PF6)2 (denoted as Ag62S12) with identical surface anatomy and size, but without a central S2– atom in the core, gives an improved yield (95%) in a short time and exhibits higher reactivity. Multiple characterization techniques (single-crystal X-ray diffraction, nuclear magnetic resonance (1H and 31P), electrospray ionization mass spectrometry, energy dispersive X-ray spectroscopy, Brunauer–Emmett–Teller (BET), Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, and thermogravimetric analysis) confirm the formation of Ag62S12-S. The BET results expose the total active surface area in supporting a single e– transfer reaction mechanism. Density functional theory reveals that leaving the central S atom of Ag62S12-S leads to higher charge transfer from Ag62S12 to the reactant, accelerates the decarboxylation process, and correlates the catalytic properties with the structure of the nanocatalyst.