A magnetic γ-Fe₂O₃@PANI@TiO₂ core–shell nanocomposite for arsenic removal via a coupled visible-light-induced photocatalytic oxidation– adsorption process†

Authors

Yuan Wang, Sichuan University
Ping Zhang, Sichuan University
Tian Zhang, University of Nebraska - LincolnFollow
Gang Xiang, Sichuan University
Xinlong Wang, Sichuan University
Simo Pehkonen, University of Eastern Finland
Shaojun Yuan, Sichuan University

Document Type

Article

Date of this Version

3-30-2020

Citation

Nanoscale Adv., 2020, 2, 2018. DOI: 10.1039/d0na00171f

Comments

open acess

Abstract

Arsenic polluted groundwater impairs human health and poses severe threats to drinking water supplies and ecosystems. Hence, an efficient method of simultaneous oxidation of As_(III) to As_(V), and removal of As_(V) from water has triggered increasing attention. In this study, a magnetic γ-Fe₂O₃ core–shell heterojunction nanocomposite was synthesized by means of hydrothermal crystallization of TiO₂ on the surface of the magnetic core–shell loaded with polyaniline (γ-Fe₂O₃@PANI@TiO₂). As an efficient photocatalyst coupled with adsorption, γ-Fe₂O₃@PANI@TiO₂ has a high light utilization and good adsorption capacity. Notably, the nanocomposite has excellent stability at various initial pH values with good reusability. Among the co-existing ions investigated, PO₄^3- has the greatest competitive reaction. The photocatalytic oxidation of As_(III) on γ-Fe₂O₃@PANI@TiO₂ is dominated by the synergy of several active substances, with superoxide free radicals and photogenerated holes being the major players.