Zhang Xiao-Han, Zhang Meng-Tian, Du Hong-Gang, Huang Hai-Hua, Zhang Xue-Feng, Wen Xia, Wang Li-Dong, Deng Wei-Zhen, He Yu-Mei, Bai Jie, Ding Li-Wen, He Chun-Ting
Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education, College of Chemistry and Materials, Jiangxi Normal University, Nanchang, 330022, China.
Analysis, and Test Center, Guangzhou University of Technology, Guangzhou, 510006, China.
Angew Chem Int Ed Engl. 2025 Aug 11;64(33):e202507040. doi: 10.1002/anie.202507040. Epub 2025 Jun 25.
Cathode reconstruction is equally crucial for water electrolysis, yet it has received less attention than anode. Lattice selenium (Se) doping is an effective strategy to improve hydrogen evolution reaction (HER) of metal-based electrocatalysts in cathodes, but many fundamental questions concerning the actual role of Se on the active species as well as catalytic kinetics remain to be clarified, especially in those electrocatalytic self-reconstruction systems. Here, we showcase the accelerated two-stage structural evolution of Se-doped cobalt phosphide (Se-CoP) during alkaline HER by operando X-ray absorption spectroscopy and powder X-ray diffraction, combined with high-resolution transmission electron microscopy (HRTEM) analysis. Further density functional theory (DFT) calculations suggest that the in situ formed dual-component heterostructure of highly crystalline Co(OH) and robust Co nanoclusters, which are decorated with residual Se, is responsible for the high HER performance. The reconstructed Se-CoP on carbon cloth delivers a low overpotential of 79 ± 2 mV at 100 mA · cm and achieves an impressive charge transfer amount of 6.3 × 10 C cm operating at 500 mA cm, surpassing the reported electrocatalysts constructed by non-noble metal phosphides. This work provides brand-new perspectives on the self-reconstruction perturbed by heteroatoms for well-designed composite electrocatalysts.
阴极重构对于水电解同样至关重要，但相较于阳极，它受到的关注较少。晶格硒（Se）掺杂是一种提高阴极中金属基电催化剂析氢反应（HER）的有效策略，但许多关于Se在活性物种上的实际作用以及催化动力学的基本问题仍有待阐明，特别是在那些电催化自重构体系中。在此，我们通过原位X射线吸收光谱和粉末X射线衍射，并结合高分辨率透射电子显微镜（HRTEM）分析，展示了碱性HER过程中Se掺杂磷化钴（Se-CoP）加速的两阶段结构演变。进一步的密度泛函理论（DFT）计算表明，原位形成的由高度结晶的Co(OH)和负载有残余Se的坚固Co纳米团簇组成的双组分异质结构，是高HER性能的原因。碳布上重构的Se-CoP在100 mA·cm时具有79±2 mV的低过电位，在500 mA cm下运行时实现了令人印象深刻的6.3×10 C cm的电荷转移量，超过了报道的由非贵金属磷化物构建的电催化剂。这项工作为设计良好的复合电催化剂中受杂原子干扰的自重构提供了全新的视角。
