Polymetallic layered double hydroxides are promising cost-effective catalysts for the oxygen evolution reaction (OER) due to their versatile anionic and cationic tunability. Nevertheless, several challenges persist, notably, issues related to low electrical conductivity, poor catalytic activity, and stability, especially at high current density. Herein, we report the design of Ce- and La-doped CoNiFe-layered double hydroxide (CeLaCoNiFe-LDH) nanosheets through a facile and scalable in situ self-assembly strategy that displays enhanced OER activity. Experimental and theoretical investigations provide insights into the impact of Ce-and La-doping by comparing CeCoNiFe-LDH, LaCoNiFe-LDH, and pristine CoNiFe-LDH, all synthesized using the same methodology. These results reveal that doping Ce³⁺ and La³⁺ into CoNiFe-LDH substantially improves its electronic structure, resulting in enhanced conductivity, more oxygen vacancies (Vo), electron interaction, and active site formation. Consequently, significantly reduced overpotentials of 175, 314, and 424 mV at 10, 100, and 500 mA cm⁻², respectively, and a highly stable current density of 120 h in 1 M KOH were achieved. Notably, these performance metrics surpass those of unmodified LDHs and are competitive with many lanthanide-doped transition metal-based LDH electrocatalysts, as well as noble metal catalysts like ruthenium catalysts. This work represents a pioneering effort in doping Ce³⁺ and La³⁺ ions into a functional CoNiFe-based electrocatalyst, offering inspiring OER performance and scalability potential.

多金属层状双氢氧化物由于其多功能的阴离子和阳离子可调性而成为析氧反应（OER）中极具成本效益的催化剂。然而，仍然存在一些挑战，特别是与低电导率、催化活性差和稳定性相关的问题，特别是在高电流密度下。在此，我们报告了通过简单且可扩展的原位自组装策略设计了 Ce 和 La 掺杂的 CoNiFe 层状双氢氧化物 (CeLaCoNiFe-LDH) 纳米片，该策略显示出增强的 OER 活性。实验和理论研究通过比较使用相同方法合成的 CeCoNiFe-LDH、LaCoNiFe-LDH 和原始 CoNiFe-LDH，深入了解 Ce 和 La 掺杂的影响。这些结果表明，在 CoNiFe-LDH 中掺杂 Ce ³⁺ 和 La ³⁺ 显着改善了其电子结构，从而提高了电导率、更多的氧空位 (Vo)、电子相互作用和活性位点形成。因此，在 10、100 和 500 mA cm ⁻² 下，过电位分别显着降低为 175、314 和 424 mV，并在 1 M KOH 中实现了 120 小时的高度稳定的电流密度。值得注意的是，这些性能指标超过了未修饰的 LDH，并且与许多稀土掺杂过渡金属基 LDH 电催化剂以及钌催化剂等贵金属催化剂具有竞争力。这项工作代表了将 Ce ³⁺ 和 La ³⁺ 离子掺杂到功能性 CoNiFe 基电催化剂中的开创性努力，提供了鼓舞人心的 OER 性能和可扩展潜力。