It is still a huge challenge to develop highly efficient and low-cost non-precious metal-based electrocatalysts for overall water splitting in alkaline electrolytes. Herein, Cr and Fe co-doped CoP porous mesh nanosheets (Mesh-CrFe-CoP NSs) were synthesized through hydrolysis reaction, ion exchange etching and subsequent low-temperature phosphating process. The Mesh-CrFe-CoP NSs provides overpotentials at a current density of 10 mA cm⁻² under alkaline electrolyte of 103.7 mV and 256.4 mV for HER and OER, respectively. Furthermore, when using Mesh-CrFe-CoP NSs as anode and cathode, the water splitting system could afford a current density of 10 mA cm^–2 at 1.55 V, which is better than an electrolytic cell composed of 20% Pt/C and RuO₂. The excellent electrocatalytic performance of Mesh-CrFe-CoP NSs is attributed to the co-doping and porous nanostructure. Specifically, the Cr and Fe co-doped porous CoP nanosheets electrocatalyst not only provided abundant exposure active sites, accelerated the entry of liquid and the diffusion of gas, but also regulated the electronic environment of active sites, and thus enhanced the electrochemical performance. This work proposes a strategy for the rational design of highly efficient and stable non-precious metal co-doped phosphide electrocatalysts in the of electrochemical water splitting.

开发高效、低成本的非贵金属基电催化剂用于碱性电解质中的整体水分解仍然是一个巨大的挑战。在此，通过水解反应、离子交换蚀刻和随后的低温磷化工艺合成了Cr和Fe共掺杂的CoP多孔网状纳米片（Mesh-CrFe-CoP NSs）。Mesh-CrFe-CoP NSs 在 10 mA cm ^-2的电流密度下，在碱性电解质 103.7 mV 和 256.4 mV 下为 HER 和 OER提供过电位。此外，当使用 Mesh-CrFe-CoP NSs 作为阳极和阴极时，水分解系统可以在 1.55 V下提供 10 mA cm ^–2的电流密度，这优于由 20% Pt/C 和 RuO 组成的电解池₂. Mesh-CrFe-CoP NSs 优异的电催化性能归功于共掺杂和多孔纳米结构。具体而言，Cr和Fe共掺杂的多孔CoP纳米片电催化剂不仅提供了丰富的暴露活性位点，加速了液体的进入和气体的扩散，而且调节了活性位点的电子环境，从而提高了电化学性能。这项工作提出了一种在电化学水分解中合理设计高效稳定的非贵金属共掺杂磷化物电催化剂的策略。