High-Entropy Single-Atom Catalyst as Coreactant Accelerator for Reactive Oxygen Species-Mediated Electrochemiluminescence

作者：Fuad Abduro Bushira, Shengwu Wen, Zhuangqiang Gao, Jing Xu, Haifeng Dong · 发表于：Analytical Chemistry · 年份：2025 · DOI：10.1021/acs.analchem.5c01342 · 被引用次数：21 · 研究领域：Advanced biosensing and bioanalysis techniques、Electrochemical Analysis and Applications、Advanced Nanomaterials in Catalysis

Single-atom catalysts (SACs) have garnered significant attention as coreactant accelerators in luminol-dissolved O 2 electrochemiluminescence (ECL) systems, but designing and fabricating highly efficient SACs remain a critical challenge. In this study, we present the first attempt to develop a high-entropy single-atom catalyst (HE-SAC) by rationally and atomically modulating multiple isolated heteroatom active sites (Fe, Co, Cu, Ni, and Mn) in M–N 4 coordination moieties within pyridinic and pyrrolic nitrogen-rich graphitic frameworks. This HE-SAC features a square-planar geometric structure with low symmetry and a highly localized electron distribution, leading to enhanced catalytic activity for reactive oxygen species (ROS) generation and, consequently, improved luminol ECL performance. Synchrotron radiation analysis and density functional theory (DFT) calculations indicate that Mn–N 4 and Co–N 4 function as electron delocalizers to modulate the catalytic activity of Fe sites during O 2 activation, while Ni–N 4 and Cu–N 4 promote weak binding with intermediates. The unique electronic structure and synergistic interaction among the HE-SAC metal active sites enhance the catalytic activity, boosting ROS production. The interactions between active sites and the graphenic support leverage high entropy to further boost the HE-SAC durability and catalytic efficiency. Furthermore, the incorporation of luminol-modified AgNPs with HE-SAC significantly enhances the ECL signal, resulti...