Promotion of alkaline hydrogen production via Ni‐doping of atomically precise Ag nanoclusters

Abstract

Alloy catalysts are widely used in electrocatalytic hydrogen production because of the synergistic effect produced by constituent metals. However, an atomiclevel understanding of the alloy effect remains elusive because of their polydispersity. In this study, we investigated the effects of an atomically precise Ag 25 nanocluster catalyst doped with a single Ni atom in an alkaline electrolyte on the hydrogen evolution reaction (HER). The synthesized NiAg 24 nanoclusters exhibited significantly altered electronic structures and reduction potentials, leading to substantially reduced overpotentials and enhanced HER activity. Tafel analysis revealed that Ni doping drastically improved the sluggish Volmer step. Density functional theory studies further revealed that the hydrogen adsorption energy was substantially reduced upon Ni doping, which accounted for the enhanced HER activity observed for the NiAg 24 nanoclusters.

Hydride‐containing 2‐Electron Pd/Cu Superatoms as Catalysts for Efficient Electrochemical Hydrogen Evolution

“…It is interesting to note that the TOF values obtained for PdHCu 11 are higher than most efficient singleatom catalysts, including Pt single-atom catalysts, under similar conditions (Figure 4e and Table S2). More specifically, compared to other bimetallic nanoclusters reported to be efficient HER electrocatalysts (Table S3), [14,[30][31][32][33][34][35] it is the one with the best activity. Evidently, the Pd atom in PdHCu 11 is fully utilized for H 2 production, presumably owing to its unique open structure.…”

Recent advances in atomically precise metal nanoclusters for electrocatalytic applications

“…Lee and co-workers investigated the doping of a single nickel atom in the core of NCs on the HER by the construction of Ag 25 and NiAg 24 . 25 The study demonstrated that Ag 25 and NiAg 24 exhibited distinct electronic structures as well as redox properties. In alkaline electrolytes, the rate-determining step of the HER is usually the Volmer step, owing to the high energy barrier for dissociating water.…”

Atomically precise Au and Ag nanoclusters doped with a single atom as model alloy catalysts

“…It is, for example, used in the synthesis of AuAg 24 (SR) 18 by mixing Ag 25 (SR) 18 and Au(PPh 3 )Cl (entry 9, Table 1), where Ag 0 is oxidized and then dissolved in solution, while Au + is reduced and deposited on the NC (Scheme 2b). 46,57,62 On the other hand, MAu 24 (SR) 18 (M = Cd or Hg) was synthesized by mixing Au 25 (SR) 18 with M(NO 3 ) 2 (entries 6 and 7, Table 1). 41,53 This process is called anti-galvanic replacement and is specific to small metal NCs, where the most electronegative Au is dissolved as Au + in solution (Scheme 2c).…”

“…This section presents an overview of the syntheses and structures of three types of SAD Au/Ag NCs as well as the corresponding pure Au/Ag NCs treated in this review (Tables 1–3). 39–63 The atomic packing structures and the dopant locations were determined by a combination of methods, including SCXRD, 57,58,61,63–69 nuclear magnetic resonance (NMR) spectroscopy, 40,70 X-ray absorption fine structure (XAFS) spectroscopy. 39,44,45,60,71,72 high-resolution transmission electron microscopy (HRTEM), 59,73,74 and density functional theory (DFT) calculations.…”