Manipulating the Adjacent Microenvironment of Atomically Dispersed FeN 4 Sites via Cross-Link-Induced 3D Carbon Nest for Efficient Oxygen Reduction

作者：Tonghui Zhao, Guangjin Wang, Dongdong Xiao, Min Young Song, Yanmin Hu, Tingting Chao, Yapeng Li, Yapeng Li, Zedong Zhang, Yun Lu, Mingxing Gong, Tao Shen, Deli Wang, Huile Jin, Dingsheng Wang, Wei Chen, Yadong Li, Yadong Li · 发表于：ACS Catalysis · 年份：2025 · DOI：10.1021/acscatal.4c06546 · 被引用次数：10 · 研究领域：Electrocatalysts for Energy Conversion、Advanced Photocatalysis Techniques、Fuel Cells and Related Materials

Electronic perturbation induced by the microenvironment regulation adjacent to the FeN 4 sites anchored on metal–N–C materials will accelerate its oxygen reduction reaction (ORR) kinetics. Herein, we report a fine-tuning in the charge configuration of FeN 4 sites through a defect-rich N/S-doped carbon nest derived from the chemically cross-linked pyrrole/thiophene copolymer (CCPPT) with a sp 3 -hybridized cross-linker. Compared with the pyrrole/thiophene copolymer (PPT) without the cross-linker, CCPPT with a knitted three-dimensional (3D) network delivers higher defect density and ∼2-fold sulfur retention after pyrolysis. The structural characterizations combined with theoretical calculations suggest that adjacent vacancy defects ( C vd ) and FeN 4 /S 2 moiety together induce the charge redistribution of the FeN 4 sites on the resultant CC-Fe 1 /NSC from CCPPT, reducing the adsorption strength of the oxygen-containing intermediates and the energy barrier of ORR. As expected, CC-Fe 1 /NSC shows an impressive half-wave potential of ∼0.91 V vs reversible hydrogen electrode (RHE), surpassing both the PPT-derived Fe 1 /NSC (0.88 V) and the commercial Pt/C (0.86 V). This work provides a distinctive path to manipulate the adjacent microenvironment of the single-atom catalysts toward ORR or even beyond.