Tailoring NiPt₁ single-atom alloy nanoclusters by embedded Ni₃ZnC_0.7 to accelerate alkaline hydrogen evolution

Electrocatalytic hydrogen evolution reaction (HER) faces challenges in alkaline due to competitive adsorption of *OH and *H at the same active site, which hinders H₂ generation. Single-atom alloys (SAAs), particularly Ni-based systems like NiPt₁ SAAs, show considerable performance through dual-site mechanisms, where Ni adsorbs *OH while Pt facilitates H₂ desorption. However, *OH blockage on Ni hinders *OH desorption and triggers slow water dissociation kinetics. Herein, supported NiPt₁ alloy nanoclusters embedded with Ni₃ZnC_0.7 (Ni₃ZnC_0.7@NiPt₁) are synthesized through pyrolysis of zeolitic imidazolate framework-8 (ZIF-8)@Ni coordination compound (ZIF-8@NCC) coupled with Pt galvanic replacement reactions. Experiments and calculations reveal that the embedded Ni₃ZnC_0.7 modulates electronic structure of Ni, promoting *OH desorption and enhancing water dissociation. Thus, supported Ni₃ZnC_0.7@NiPt₁ achieves exceptional low overpotential (η₁₀ = 23 mV) and high mass activity (MA₅₀ = 1.67 mA·μg_Pt⁻¹) in alkaline, which remarkably surpass Ni@NiPt₁ (η₁₀ = 127 mV and MA₅₀ = 0.101 mA·μg_Pt⁻¹). The corresponding alkaline anion-exchange membrane water electrolyzer (AEMWE) requires only 1.91 V at 1 A·cm⁻², demonstrating industrial viability. This work provides new insights into addressing *OH blockage on SAAs catalysts in alkaline HER.