“…Electrochemical water splitting presents a sustainable and environmentally benign pathway for the generation of molecular hydrogen, a clean energy carrier, via leveraging on Earth-abundant water and renewable power as feedstocks. Undoubtedly, the derivation of practical and efficient water electrolyzer technology, capable of large-scale hydrogen production, is expected to hold prospective contributions to the hydrogen economy as well as to global energy security. − Nevertheless, this approach fundamentally hinges on the development of high-performance electrocatalysts for driving the cathodic hydrogen evolution reaction (HER). , Thus far, platinum (Pt) marks the gold standard element for HER, on account of its fast reaction kinetics and near-optimal binding strength with hydrogen. − Unfortunately, the high cost associated with the precious metal, activity deterioration owing to Ostwald ripening and coalescence behaviors of Pt nanoparticles (NPs), susceptibility to leaching in corrosive electrolytes and suboptimum water dissociation kinetics in alkaline and neutral electrolytes, raises immediate and ineluctable concerns on the viability of Pt-based electrocatalysts. − On this note, electrocatalysts, as alternatives to Pt, endowed with excellent catalytic activity, durability and functionality for HER across a wide pH range are of paramount importance, yet extremely challenging. − …”