One of the challenges to realize large-scale water splitting is the lack of highly active and low-cost electrocatalysts for its two half reactions: hydrogen and oxygen evolution reactions (HER and OER). In this work, a Mo doping approach is adopted to enhance the HER and OER bifunctionality of NiFe-LDH. The catalyst MoNiFeS_x@FeNi₃ obtained after sulfidation exhibits further improved catalytic performance and good stability. In KOH solution (1.0 M), ultralow overpotentials of 67 mV and 142 mV work well to reach current densities of 10 mA cm⁻² for HER and OER, separately. In urea (0.33 M) and KOH (1.0 M) solutions, catalyst urea oxidation reaction can be significantly promoted by MoNiFeS_x@FeNi₃, and can reach a current density of 10 mA cm⁻² under the condition of 1.31 V. Most importantly, our work elaborates a facile strategy to synthesize novel trimetallic transition metal catalyst as a cut-price substitute for precious metals for highly effective overall water splitting.

实现大规模水分解的挑战之一是缺乏用于其两个半反应的高活性和低成本的电催化剂：析氢和析氧反应（HER 和 OER）。在这项工作中，采用 Mo 掺杂方法来增强 NiFe-LDH 的 HER 和 OER 双功能。硫化后得到的催化剂MoNiFeS _x @FeNi ₃表现出进一步提高的催化性能和良好的稳定性。在 KOH 溶液 (1.0 M) 中，67 mV 和 142 mV 的超低过电位可以很好地实现HER 和 OER 分别达到 10 mA cm ^{-2的电流密度。}_{在尿素 (0.33 M) 和 KOH (1.0 M) 溶液中，MoNiFeS x} @FeNi ₃可显着促进催化剂尿素氧化反应，并且在 1.31 V 的条件下可以达到 10 mA cm ^-2的电流密度。最重要的是，我们的工作阐述了一种简便的策略来合成新型三金属过渡金属催化剂作为贵金属的低价替代品，用于高效的整体水分裂。