Hollow Microsphere TiO2/ZnO p–n Heterojuction with High Photocatalytic Performance for 2,4-Dinitropheno Mineralization

Abstract

A unique hollow microsphere TiO2/ZnO p–n heterojuction was successfully fabricated via a one-step hydrothermal method for degradation of 2,4-Dinitrophenol. The enhancement of mineralization of 2,4-dinitrophenol (2,4-DNP) via photocatalytic degradation of TiO2/ZnO p–n heterojuction was investigated. The 2,4-DNP was degraded completely by TiO2/ZnO, and 78% of the total organic carbon (TOC) was removed which is greatly superior to that on the controlled TiO2, ZnO with 53%, 45%, respectively. A schematic diagram of photocatalytic oxidation mechanism of 2,4-DNP was also presented by [Formula: see text]OH radical detection. The oxidation of 2,4-DNP and the intermediate productions was based on the hydroxyl (OH) with a high oxidation potential of 2.8[Formula: see text]V. Moreover, the excellent stability and reliability of the TiO2/ZnO composite hollow microsphere photocatalyst demonstrated its promising application for removal of organic pollutant from water.