Tian Lei, Tang Zi-Jun, Hao Le-Yang, Dai Ting, Zou Jian-Ping, Liu Zhao-Qing
School of Chemistry and Chemical Engineering/Institute of Clean Energy and Materials/Guangzhou Key Laboratory for Clean Energy and Materials/Huangpu Hydrogen Innovation Center/Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou, 510006, P. R. China.
National-Local Joint Engineering Research Center of Heavy Metals Pollutants Control and Resource Utilization, Nanchang Hangkong University, Nanchang, Jiangxi, 330063, P. R. China.
Angew Chem Int Ed Engl. 2024 Apr 22;63(17):e202401434. doi: 10.1002/anie.202401434. Epub 2024 Mar 14.
Traditional HO cleavage mediated by macroscopic electron transfer (MET) not only has low utilization of HO, but also sacrifices the stability of catalysts. We present a non-redox hydroxyl-enriched spinel (CuFeO) catalyst with dual Lewis acid sites to realize the homolytic cleavage of HO. The results of systematic experiments, in situ characterizations, and theoretical calculations confirm that tetrahedral Cu sites with optimal Lewis acidity and strong electron delocalization can synergistically elongate the O-O bonds (1.47 Å → 1.87 Å) in collaboration with adjacent bridging hydroxyl (another Lewis acid site). As a result, the free energy of HO homolytic cleavage is decreased (1.28 eV → 0.98 eV). HO can be efficiently split into ⋅OH induced by hydroxyl-enriched CuFeO without MET, which greatly improves the catalyst stability and the HO utilization (65.2 %, nearly 2 times than traditional catalysts). The system assembled with hydroxyl-enriched CuFeO and HO affords exceptional performance for organic pollutant elimination. The scale-up experiment using a continuous flow reactor realizes long-term stability (up to 600 mL), confirming the tremendous potential of hydroxyl-enriched CuFeO for practical applications.
由宏观电子转移（MET）介导的传统羟基自由基（HO）裂解不仅HO利用率低，还会牺牲催化剂的稳定性。我们提出了一种具有双路易斯酸位点的非氧化还原富羟基尖晶石（CuFeO）催化剂，以实现HO的均裂。系统实验、原位表征和理论计算结果证实，具有最佳路易斯酸度和强电子离域性的四面体铜位点可以与相邻的桥连羟基（另一个路易斯酸位点）协同作用，使O-O键伸长（1.47 Å → 1.87 Å）。结果，HO均裂的自由能降低（1.28 eV → 0.98 eV）。富羟基的CuFeO在无MET的情况下可将HO高效裂解为·OH，这大大提高了催化剂的稳定性和HO利用率（65.2%，几乎是传统催化剂的2倍）。由富羟基的CuFeO和HO组装而成的体系在消除有机污染物方面表现出卓越性能。使用连续流动反应器进行的放大实验实现了长期稳定性（高达600 mL），证实了富羟基的CuFeO在实际应用中的巨大潜力。
