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Indexed by:期刊论文

Date of Publication:2018-10-05

Journal:JOURNAL OF HAZARDOUS MATERIALS

Included Journals:PubMed、SCIE

Volume:359

Page Number:186-193

ISSN No.:0304-3894

Key Words:Short chain chlorinated paraffin; Photocatalysis; Dechlorination; Polydopamine; Ag nanoparticles

Abstract:Short chain chlorinated paraffins (SCCPs) have attracted increasing attention recently due to their widespread occurrence and persistence in the environment, long-distance transport, and bioaccumulation and toxicity. For the sake of photocatalytic elimination of SCCPs, a kind of polydopamine (PDA) based photocatalyst, echinus-like Fe2O3@PDA-Ag hybrids have been synthesized via coating Fe2O3 with PDA by self-polymerization of dopamine and further loading silver nanoparticles by in situ reduction onto the surface of PDA shell. The photogenerated charges of Fe2O3@PDA-Ag hybrids exhibit long lifetime from transient photovoltage signal, which is of benefit to participate in various subsequent reaction processes before their recombination. Benefiting from the coating of PDA shell and the deposition of Ag nanoparticles, Fe2O3@PDA-Ag hybrids exhibit enhanced photocatalytic activity for the removel of SCCPs as investigated by the in situ Fourier transform infrared spectroscopy, 2.9 times as high as that of Fe2O3, due to the reactive center dot OH radicals. The density functional theory simulation demonstrates the key mechanism of the formation of conjugate bond in the dechlorination process as well as the final product of HCI. The simulation indicates that there are no regularities for the H-abstraction but the dechlorination usually occurs in the adjacent Cl atoms next to the C with H-abstraction.