Incorporating Au11 nanoclusters on MoS2 nanosheet edges for promoting the hydrogen evolution reaction at the interface

Abstract

The electrocatalytic hydrogen evolution reaction (HER) holds grip as a promising strategy to obtain renewable energy resources in the form of clean fuel – hydrogen (H₂). However, understanding the catalytic mechanism at the atomic level for sustainable and efficient production of hydrogen remains an arduous challenge. In this regard, atomically precise nanoclusters (NCs) with their molecule-like properties can be utilized for a better understanding of the mechanism at the catalytic interface, identification of active sites, and much more. Herein, we report a strategy to enhance the HER activity of the well-known electrocatalyst MoS₂ by the incorporation of atomically precise gold nanoclusters, Au₁₁(PPh₃)₇I₃. Interestingly, Au₁₁(PPh₃)₇I₃ NCs were impregnated onto MoS₂ nanosheets without protecting ligands as naked Au₁₁ clusters which have increased atom efficiency. Different loadings of Au₁₁(PPh₃)₇I₃ nanoclusters on MoS₂ nanosheets revealed the superior HER activity of 2% loading of the NCs. Theoretical calculations have shown that the nanocomposite has the optimum hydrogen adsorption energy that is crucial for efficient H₂ production. Combined experimental and theoretical results provide the atomic-level understanding of the utilization of electrochemically dormant ligand-protected NCs to accelerate the HER activity of MoS₂ nanosheets.