Transition metal phosphides are promising alternatives to the precious metal catalysts for various electrocatalysis applications. Controllable and precise surface engineering of electrocatalysts is the key challenge to enhance their performance. Herein, we demonstrate an ion-exchange strategy to produce cobalt phosphide nanowires which have a conductive core and a thickness-controlled surface layer with sulfur dopants, phosphorus vacancies, and amorphous domains. They are applied for hydrogen evolution reaction with high stability, achieving a current density of 100 mA cm^-2 at an overpotential of 114 mV. Based on both comprehensive state-of-the-art experimental characterizations and theoretical investigations, the excellent catalytic performance is attributed to increased active sites, facilitated charge transfer and transport, as well as weakened H adsorption and strengthened H₂O adsorption due to the synergistic effects of S dopants and P vacancies.

过渡金属磷化物是用于各种电催化应用的贵金属催化剂的有前途的替代品。电催化剂的可控且精确的表面工程设计是提高其性能的关键挑战。在这里，我们演示了一种离子交换策略，以生产磷化钴纳米线，该线具有导电芯和带有硫掺杂剂，磷空位和非晶域的厚度受控的表面层。它们用于氢释放反应，具有很高的稳定性，可实现100 mA cm ^-2的电流密度在114毫伏的过电位。基于最先进的综合实验表征和理论研究，优异的催化性能归因于活性位点的增加，电荷转移和运输的促进以及协同作用导致的H吸附减弱和H ₂ O吸附增强S掺杂和P空位的影响。