The Ni₃Al-based alloy has been considered as a robust catalyst for oxygen evolution reaction (OER) due to its long-term durability and acceptable activity. However, related reports about understanding the catalytic mechanism are rare and desirable. Herein, the effect of γ/γ' phase lattice mismatch on the catalytic performance caused by various cooling rates after solution heat treatment was investigated. With decreasing cooling rate, the morphologies of γ′ precipitates transformed from sphere to cube and the lattice mismatch increased from -0.172% to -0.409%. The increased lattice mismatch facilitated the formation of the active β-NiOOH phase and enhanced the intrinsic catalytic activity, resulting in the optimized OER overpotential of 240 mV at a current density of 10 mA cm⁻² with a Tafel slope of 66.1 mV dec⁻¹ and a stability of 200 h in 1 M KOH. This work reveals the lattice mismatch effect on OER and provides a potential candidate for OER.

由于其长期耐用性和可接受的活性，Ni ₃ Al 基合金被认为是析氧反应 (OER) 的强大催化剂。然而，关于理解催化机制的相关报道是罕见且可取的。在此，研究了固溶热处理后不同冷却速率引起的γ/γ'相晶格失配对催化性能的影响。随着冷却速度的降低，γ'相的形貌由球体转变为立方体，晶格失配从-0.172%增加到-0.409%。增加的晶格失配促进了活性β -NiOOH 相的形成并增强了内在催化活性，从而在 10 mA cm 的电流密度下优化了 240 mV 的 OER 过电位^-2的 Tafel 斜率为 66.1 mV dec ^-1，在 1 M KOH 中的稳定性为 200 小时。这项工作揭示了对 OER 的晶格失配效应，并为 OER 提供了一个潜在的候选者。