Cobalt Nanoclusters-Modulated Platinum–Tin Intermetallic for pH-Universal Hydrogen Evolution Electrocatalysis

Achieving satisfactory electrocatalytic activity and stability of platinum (Pt)-based catalysts for hydrogen evolution reaction (HER) in wide-pH media remains a formidable challenge. In this context, a heterostructure composed of platinum–tin intermetallic nanoparticles and cobalt nanoclusters, evenly confined in a nitrogen-doped carbon mesh (Pt₃Sn/Co@N-CM), is designed that acts as an efficient HER catalyst. Alloying Sn effectively reduces Pt usage and ensures high electrical conductivity during catalysis. Notably, the Co clusters not only accelerate water dissociation in the HER process but also form strong coupling with ordered Pt₃Sn particles, thus optimizing the Gibbs free energy for pH-universal HER intermediates. Consequently, Pt₃Sn/Co@N-CM attains 10 mA cm^–2 current densities at low overpotentials of ∼8, ∼20, and ∼41 mV in acidic, alkaline, and neutral solutions, respectively, outperforming most reported Pt-based counterparts. Additionally, excellent structural and operational stability is achieved, displaying its promising prospects. This study paves a simple avenue for developing high-performance, pH-universal HER electrocatalysts.