MoS2/α-FeOOH heterojunction composites with enhanced photo-Fenton performance
Yiqian Gao, Donghui Wang, Zehui Yu, Feng Chen
Abstract
As-synthesized MoS 2 / α -FeOOH heterojunction exhibits efficient reactivities for Fenton and photo-Fenton degradation of acid orange 7 (AO7) and sulfamethoxazole. Work functions investigated by DFT method suggest a spontaneous electron transfer from MoS 2 to α -FeOOH by constructing a type II heterojunction. The electron transfer across the heterojunction was further confirmed by XPS observation. The carrier transfer can be maintained and intensified by surface redox reaction of H 2 O 2 with the accumulated carriers, which amplifies the role of heterojunction. The reaction rate constant for photo-Fenton degradation of AO7 with MoS 2 / α -FeOOH-10 is 6.6 times higher than that of α -FeOOH. Notably, although α -FeOOH cannot absorb the 660 nm irradiation, a much-enhanced photo-Fenton degradation of AO7 with MoS 2 / α -FeOOH-10 under 660 nm irradiation further verifies the occurrence of electron transfer from MoS 2 to α -FeOOH. This work provides an in-depth observation on the role of type II heterojunction in promoting the photo-Fenton reactivity for organic degradation.