Wu Qilong, Zou Haiyuan, Mao Xin, He Jinghan, Shi Yanmei, Chen Shuangming, Yan Xuecheng, Wu Liyun, Lang Chengguang, Zhang Bin, Song Li, Wang Xin, Du Aijun, Li Qin, Jia Yi, Chen Jun, Yao Xiangdong
State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun, 130012, PR China.
Intelligent Polymer Research Institute, Australian Institute for Innovative Materials, Innovation Campus, University of Wollongong, Squires Way, North Wollongong, NSW, 2500, Australia.
Nat Commun. 2023 Oct 7;14(1):6275. doi: 10.1038/s41467-023-41947-7.
Active sites identification in metal-free carbon materials is crucial for developing practical electrocatalysts, but resolving precise configuration of active site remains a challenge because of the elusive dynamic structural evolution process during reactions. Here, we reveal the dynamic active site identification process of oxygen modified defective graphene. First, the defect density and types of oxygen groups were precisely manipulated on graphene, combined with electrocatalytic performance evaluation, revealing a previously overlooked positive correlation relationship between the defect density and the 2 e oxygen reduction performance. An electrocatalytic-driven oxygen groups redistribution phenomenon was observed, which narrows the scope of potential configurations of the active site. The dynamic evolution processes are monitored via multiple in-situ technologies and theoretical spectra simulations, resolving the configuration of major active sites (carbonyl on pentagon defect) and key intermediates (*OOH), in-depth understanding the catalytic mechanism and providing a research paradigm for metal-free carbon materials.
在无金属碳材料中识别活性位点对于开发实用的电催化剂至关重要，但由于反应过程中难以捉摸的动态结构演变过程，解析活性位点的精确构型仍然是一个挑战。在此，我们揭示了氧修饰缺陷石墨烯的动态活性位点识别过程。首先，在石墨烯上精确调控缺陷密度和氧基团类型，并结合电催化性能评估，揭示了缺陷密度与2e氧还原性能之间先前被忽视的正相关关系。观察到电催化驱动的氧基团重新分布现象，这缩小了活性位点潜在构型的范围。通过多种原位技术和理论光谱模拟监测动态演变过程，解析了主要活性位点（五角形缺陷上的羰基）和关键中间体（*OOH）的构型，深入理解了催化机理，并为无金属碳材料提供了一种研究范式。
