Liu Xi, Chen Zhen, Meng Hao, Chen Jiawen, Yang Lin, Jin Mingliang, Wang Xin, Chen Zhongwei
Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou, 510006, China.
Institute of Carbon Neutrality, Zhejiang Wanli University, Ningbo, 315100, China.
Small. 2025 Oct;21(39):e07116. doi: 10.1002/smll.202507116. Epub 2025 Sep 4.
Developing cost-effective, stable hydrogen evolution reaction (HER) electrocatalysts effective across pH-Universal remains challenging. This work reports a one-pot synthesized Pt-Fe-Ni-Mo-Co high-entropy alloy catalyst supported on Ketjen Black (HEA@KB) featuring stacked nanoparticles. By systematically tuning the iron coordination, the optimized HEA@KB demonstrates outstanding HER activity with low overpotentials of 12.44 mV in acidic (0.5 m HSO), 61.35 mV in alkaline (1 m KOH), and 55.71 mV in neutral (1 m PBS) electrolytes at 10 mA cm, significantly outperforming commercial 20 wt.% Pt/C catalysts. Density functional theory (DFT) calculations reveal that Fe incorporation modulates the electronic structure of Pt active sites by downshifting the d-band center, weakening Pt-H bonds, and facilitating hydrogen desorption via the Tafel step. Concurrently, Fe enhances the density of states near the Fermi level and optimizes the local Pt coordination environment, increasing the hydrogen-targeted charge flux (HTCF) that accelerates electron transfer in the Volmer step. Electron microscopy confirms that Fe tuning governs nanoparticle stacking, thereby expanding the electrochemically active surface area. This work elucidates the dual kinetic promotion of Volmer and Tafel steps through electronic and structural synergy, offering a promising avenue for designing efficient, durable, and low-Pt HER electrocatalysts.
开发出在全pH范围内都具有成本效益且稳定的析氢反应（HER）电催化剂仍然具有挑战性。这项工作报道了一种在科琴黑（Ketjen Black，KB）上负载的一锅法合成的Pt-Fe-Ni-Mo-Co高熵合金催化剂（HEA@KB），其具有堆叠的纳米颗粒。通过系统地调节铁的配位，优化后的HEA@KB在10 mA cm时在酸性（0.5 m HSO）、碱性（1 m KOH）和中性（1 m PBS）电解质中分别表现出12.44 mV、61.35 mV和55.71 mV的低过电位，展现出出色的HER活性，显著优于商业20 wt.% Pt/C催化剂。密度泛函理论（DFT）计算表明，铁的掺入通过降低d带中心来调节Pt活性位点的电子结构，削弱Pt-H键，并通过塔菲尔步骤促进氢的脱附。同时，铁提高了费米能级附近的态密度，并优化了局部Pt配位环境，增加了氢靶向电荷通量（HTCF），从而加速了Volmer步骤中的电子转移。电子显微镜证实，铁的调节控制着纳米颗粒的堆叠，从而扩大了电化学活性表面积。这项工作阐明了通过电子和结构协同作用对Volmer和Tafel步骤的双重动力学促进作用，为设计高效、耐用且低铂的HER电催化剂提供了一条有前景的途径。
