title: Enhanced Fenton Catalytic Efficiency of γ-Cu-Al₂O₃ by σ-Cu²⁺-Ligand Complexes from Aromatic Pollutant Degradation.
abstract: Mesoporous Cu-doped γ-Al2O3 (γ-Cu-Al2O3) was prepared via an evaporation-induced self-assembly process, in which Cu(+/2+) was co-incorporated into mesoporous γ-Al2O3 by chemical bonding of Al-O-Cu. The catalyst was found to be highly effective and stable for the degradation and mineralization of aromatic pollutants, as demonstrated with bisphenol A, 2,4-dichlorophenoxyacetic acid, ibuprofen, diphenhydramine, and phenytoin in the presence of H2O2 under neutral pH conditions. In addition, the high utilization efficiency of H2O2 was maintained at approximately 90% prior to the disappearance of the initial aromatic pollutants. On the basis of all of the characterization results, the pollutant degradation processes predominantly occurred on the surface of the catalyst due to the formation of σ-Cu-ligand complexes between the phenolic OH group and the surface Cu. In the reaction system, in addition to the unselective oxidation by (•)OH, H2O2 directly attacked the σ-Cu(2+)-complexes aromatic ring with the phenolic OH group, which resulted in the formation of (•)OH and HO-adduct radicals that were oxidized to hydroxylation products by reduction of Cu(2+) in the σ-Cu(2+)-complexes to Cu(+). The process prevented Cu(2+) from oxidizing H2O2 to form HO2(•)/O2(•-) or O2, and enhanced the Cu(+)/Cu(2+) cycle, the formation of (•)OH, and the utilization efficiency of H2O2. Therefore, an extraordinarily high degradation and mineralization of the aromatic pollutants was observed.
authors.affiliation: †Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.|‡University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Lai
authors.initials: L
authors.lastname: Lyu
authors.affiliation: †Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Lili
authors.initials: L
authors.lastname: Zhang
authors.affiliation: †Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Qiyuan
authors.initials: Q
authors.lastname: Wang
authors.affiliation: †Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Yulun
authors.initials: Y
authors.lastname: Nie
authors.affiliation: †Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.|‡University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Chun
authors.initials: C
authors.lastname: Hu
mesh_terms: D015084:2,4-Dichlorophenoxyacetic Acid / Q000737:chemistry; D000537:Aluminum Oxide / Q000737:chemistry*; D001559:Benzhydryl Compounds / Q000737:chemistry; D002384:Catalysis; D004785:Environmental Pollutants / Q000737:chemistry*; D006841:Hydrocarbons, Aromatic / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007501:Iron; D008024:Ligands; D010084:Oxidation-Reduction; D010636:Phenols / Q000737:chemistry; D000098826:Bisphenol A Compounds
chemical_list: D015084:2,4-Dichlorophenoxyacetic Acid; D000537:Aluminum Oxide; D001559:Benzhydryl Compounds; D004785:Environmental Pollutants; D006841:Hydrocarbons, Aromatic; D006861:Hydrogen Peroxide; D007501:Iron; D008024:Ligands; D010636:Phenols; C045076:Fenton's reagent; C006780:bisphenol A; D000098826:Bisphenol A Compounds