title: Structure and catalytic activities of ferrous centers confined on the interface between carbon nanotubes and humic acid.
abstract: Preparation of heterogeneous catalysts with active ferrous centers is of great significance for industrial and environmental catalytic processes. Nanostructured carbon materials (NCM), which possess free-flowing π electrons, can coordinate with transition metals, provide a confinement environment for catalysis, and act as potential supports or ligands to construct analogous complexes. However, designing such catalysts using NCM is still seldom studied to date. Herein, we synthesized a sandwich structured ternary complex via the coordination of Fe-loaded humic acid (HA) with C=C bonds in the aromatic rings of carbon nanotubes (CNTs), in which the O/N-Fe-C interface configuration provides the confinement environment for the ferrous sites. The experimental and theoretical results revealed octahedrally/tetrahedrally coordinated geometry at Fe centers, and the strong hybridization between CNT C π* and Fe 3d orbitals induces discretization of the atomic charges on aromatic rings of CNTs, which facilitates O2 adsorption and electron transfer from carbon to O2, which enhances O2 activation. The O2 activation by the novel HA/Fe-CNT complex can be applied in the oxidative degradation of phenol red (PR) and bisphenol A (BPA) in aqueous media.
authors.affiliation: CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, CAS Key Laboratory of Nuclear Radiation and Nuclear Energy Technology, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China. dwang@ihep.ac.cn fengwy@ihep.ac.cn.
authors.forename: Bing
authors.initials: B
authors.lastname: Wang
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Zhou
authors.forename: Dongqi
authors.initials: D
authors.lastname: Wang
authors.forename: Jun-Jie
authors.initials: JJ
authors.lastname: Yin
authors.forename: Hanqing
authors.initials: H
authors.lastname: Chen
authors.forename: Xingfa
authors.initials: X
authors.lastname: Gao
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.forename: Kurash
authors.initials: K
authors.lastname: Ibrahim
authors.forename: Zhifang
authors.initials: Z
authors.lastname: Chai
authors.forename: Weiyue
authors.initials: W
authors.lastname: Feng
authors.forename: Yuliang
authors.initials: Y
authors.lastname: Zhao
mesh_terms: D000327:Adsorption; D001559:Benzhydryl Compounds / Q000737:chemistry; D002244:Carbon / Q000737:chemistry; D002384:Catalysis; D004578:Electron Spin Resonance Spectroscopy; D004583:Electrons; D006812:Humic Substances; D006861:Hydrogen Peroxide / Q000737:chemistry; D007477:Ions; D007501:Iron / Q000737:chemistry; D008024:Ligands; D008670:Metals / Q000737:chemistry; D037742:Nanotubes, Carbon / Q000737:chemistry*; D016011:Normal Distribution; D010100:Oxygen / Q000737:chemistry; D010636:Phenols / Q000737:chemistry; D010637:Phenolsulfonphthalein / Q000737:chemistry; D014867:Water / Q000737:chemistry; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D002244:Carbon; D006812:Humic Substances; D006861:Hydrogen Peroxide; D007477:Ions; D007501:Iron; D008024:Ligands; D008670:Metals; D037742:Nanotubes, Carbon; D010100:Oxygen; D010636:Phenols; D010637:Phenolsulfonphthalein; D014867:Water; C006780:bisphenol A; D000098826:Bisphenol A Compounds