@article{Li2023, 
author = {Le Li and Na Li and Jia-Wei Xia and Shi-Long Zhou and Xing-Yue Qian and Feng-Xiang Yin and Guo-Hong Dai and Guang-Yu He and Hai-Qun Chen},
title = {A pH-universal ORR catalyst with atomic Fe-heteroatom (N, S) sites for high-performance Zn-air batteries},
year = {2023},
journal = {Nano Research},
volume = {16},
number = {7},
pages = {9416-9425},
keywords = {heteroatom dopant, single-atom electrocatalyst, FeN3S sites, Zn-air battery, density functional theory (DFT) study},
url = {https://www.sciopen.com/article/10.1007/s12274-023-5625-y},
doi = {10.1007/s12274-023-5625-y},
abstract = {Developing innovative, easy-to-manufacture, and non-Pt-group-metal (non-PGM) electrocatalysts is essential for the highly efficient oxygen reduction reaction (ORR). Herein, we report a self-sacrificing post-synthetic strategy to synthesize highly loaded Fe-isolated single atoms anchored on the hierarchical porous N,S co-doped carbon matrix (Fe-SAs/S,N-C/rGO). The optimized Fe-SAs/S,N-C/rGO exhibits excellent ORR activity in the pH-universal range with half-wave potentials of 0.89, 0.80, and 0.60 V in alkaline, acidic, and neutral media, comparable to the commercial Pt/C (0.85, 0.81, and 0.64 V, respectively). The homemade liquid Zn-air battery (ZAB) with Fe-SAs/S,N-C/rGO as the cathode catalyst displays an open-circuit voltage (OCV) of ~ 1.61 V, discharging specific capacity of 817.23 mAh·g−1, and long-term durability of ~ 1865 cycles, outperforming those of the device with commercial Pt/C+RuO2 (1.49 V, 657.32 mAh·g−1, and ~ 120 cycles, respectively). Intriguingly, the corresponding flexible solid-state ZAB delivers satisfactory OCV, peak power density, foldability, and cycling stability at room temperature, as well as adaptability at a low temperature of −10 °C. Besides, density functional theory (DFT) calculation reveals that the atomic FeN3S moieties in Fe-SAs/S,N-C/rGO can cause charge redistribution and lower the binding strength of oxygen-containing intermediates, resulting in accelerated ORR kinetics and optimized catalytic activity. This work provides insights into experimental and theoretical guidance towards non-PGM electrocatalysts for efficient energy conversion.}
}