Lee Jaehun, Shin Hyunsub, Jeong Harim, Jang Dowon, Kim Younghwon, Im Younghwan, Kang Misook
Department of Chemistry, College of Natural Sciences, Yeungnam University, Gyeongsan, Gyeongbuk, 38541, Republic of Korea.
Korea Research Institute of Chemical Technology (KRICT), 141 Gajeong-ro, Yuseong-gu, Daejeon, 34114, Republic of Korea.
Small. 2025 Sep;21(35):e2504031. doi: 10.1002/smll.202504031. Epub 2025 Jul 11.
Designing HER catalysts that autonomously adapt to acidic environments remains a critical challenge for scalable hydrogen production. Here, a multifunctional, self-stabilizing electrocatalyst-C@Cd₀.₉Ni₀.₁S-featuring a dynamically responsive Ni-S vacancy interface embedded in a conductive carbon matrix is presented. Ni doping induces local electron accumulation and facilitates sulfur vacancy formation, thereby reprogramming the electronic structure to lower the hydrogen adsorption free energy (ΔG) and promote hydrogen spillover. Sulfur vacancies enhance charge redistribution and proton binding, while carbon encapsulation ensures charge continuity and structural durability under acidic stress. The catalyst achieves a low overpotential of -0.24 V at 100 mA cm for 10 days and maintains stable operation at 500 mA cm without metal leaching. DFT and operando XPS analyses confirm that the Ni-S vacancy interface adaptively modulates electronic structure and interfacial reactivity, enabling intelligent surface response during HER. This work establishes a rational design framework for acid-stable, precious-metal-free HER catalysts with autonomous interface regulation.
设计能够自主适应酸性环境的析氢反应（HER）催化剂，对于可扩展的制氢技术而言仍然是一项重大挑战。在此，我们展示了一种多功能、自稳定的电催化剂——C@Cd₀.₉Ni₀.₁S，其具有嵌入导电碳基体中的动态响应性Ni-S空位界面。镍掺杂导致局部电子积累并促进硫空位的形成，从而重新编程电子结构以降低氢吸附自由能（ΔG）并促进氢溢流。硫空位增强了电荷重新分布和质子结合，而碳封装确保了在酸性应力下的电荷连续性和结构耐久性。该催化剂在100 mA cm²下实现了-0.24 V的低过电位，持续10天，并在500 mA cm²下保持稳定运行且无金属浸出。密度泛函理论（DFT）和原位X射线光电子能谱（XPS）分析证实，Ni-S空位界面可自适应调节电子结构和界面反应性，从而在析氢反应过程中实现智能表面响应。这项工作为具有自主界面调控的耐酸、无贵金属析氢反应催化剂建立了合理的设计框架。
