2D heterointerface-entrapped Pt single-atoms for exceptionally stable hydrogen evolution catalysts

Abstract

Hydrogen, as a zero-emission and renewable energy source, is crucial for overcoming environmental concerns. Electrochemical water splitting catalysts are key for efficient hydrogen production, with platinum-based catalysts being highly effective but hindered by high cost. Non-noble metal materials and single-atom (SA) catalysts have been explored, with 2D materials like $MoS_2$ gaining attention. However, challenges persist in maximizing catalytically active edge sites and utilizing the inert basal plane of MoS2. In this study, we suggest a novel catalyst—a 2D heterostructure of N-doped graphene (NGr) and MoS2, functionalized with Pt SAs ($Pt_1/NGr-MoS_2$). This catalyst simultaneously activates the 2D heterostructure and stabilizes the metastable 1T phase of MoS2 for prolonged operation, exhibiting high hydrogen evolution reaction (HER) performance with a low overpotential of $210 mV$ and remarkable long-term stability over 30,000 cycles. Computational calculations confirm the stable environment for $1T MoS_2$ formation. The $Pt_1/NGr-MoS_2$ catalyst demonstrates outstanding HER performance in acidic conditions, modulating electronic configuration for improved kinetic activity with experimental and calculational results. Moreover, the stabilized Pt SAs effectively suppress the phase transition of $1T MoS_2$, ensuring exceptional stability. This research presents a promising advancement in developing cost-effective and stable catalysts for commercial hydrogen evolution reactions, bridging the gap towards efficient and prolonged operation.