Zhao Dantong, Jiao Dongxu, Yi Lingya, Yu Yang, Zou Jiajia, Cui Xiaoqiang, Hu Weihua
School of Materials and Energy, Chongqing Key Laboratory of Battery Materials and Technology, Southwest University, Chongqing, 400715, P. R. China.
State Key Laboratory of Automotive Simulation and Control, School of Materials Science and Engineering, Key Laboratory of Automobile Materials of MOE, Jilin University, Changchun, 130012, P. R. China.
Small. 2024 Dec;20(50):e2406890. doi: 10.1002/smll.202406890. Epub 2024 Sep 20.
Oxygen-doped carbon materials show great promise to catalyze two-electron oxygen reduction reaction (2e-ORR) for electrochemical synthesis of hydrogen peroxide (HO), but the identification of the active sites is the subject of ongoing debate. In this study, a tandem oxidation strategy is developed to activate carbon black for achieving highly efficient electrochemical synthesis of HO. Acetylene black (AB) is processed with O plasma and subsequent electrochemical oxidation, resulting in a remarkable selectivity of >96% over a wide potential range, and a record-setting high yield of >10 mol g h with good durability in gas diffusion electrode. Comprehensive characterizations and calculations revealed that the presence of abundant C═O groups at the edge sites positively correlated to and accounted for the excellent 2e-ORR performance. Notably, the edge hydroquinone group formed from quinone under operando conditions, which is overlooked in previous research, is identified as the most active catalytic site.
氧掺杂碳材料在催化两电子氧还原反应（2e-ORR）以电化学合成过氧化氢（HO）方面显示出巨大潜力，但活性位点的识别仍是一个存在争议的话题。在本研究中，开发了一种串联氧化策略来活化炭黑，以实现高效的HO电化学合成。乙炔黑（AB）经过氧等离子体处理和随后的电化学氧化，在很宽的电位范围内具有超过96%的显著选择性，在气体扩散电极中具有创纪录的>10 mol g h的高产率和良好的耐久性。综合表征和计算表明，边缘位点处大量C═O基团的存在与优异的2e-ORR性能呈正相关，并解释了该性能。值得注意的是，在操作条件下由醌形成的边缘对苯二酚基团被确定为最活跃的催化位点，而这在先前的研究中被忽视了。
