Photocatalytic generation of H ₂O ₂ over a Z-scheme Fe ₂O ₃@C@1T/2H-MoS ₂ heterostructured catalyst for high-performance Fenton reaction

Abstract

A Z-scheme Fe ₂O ₃@C@1T/2H-MoS ₂ heterostructured catalyst is constructed using carbon and 1T-MoS ₂ as bridging layers, realizing high-performance H ₂O ₂ generation and a self-sufficient heterogeneous photo-Fenton reaction.

Abstract

The wide application of the Fenton reaction has been severely restricted by the requirement of continuous feeding of H ₂O ₂, the iron-slurry production, and the slow recycle rate of Fe ³⁺/Fe ²⁺. This work reports transforming type-II Fe ₂O ₃@2H-MoS ₂ heterostructures to a Z-scheme Fe ₂O ₃@C@1T/2H-MoS ₂ catalyst capable of photocatalytic in situ generation of H ₂O ₂ as an oxidant for the subsequent Fenton reaction. With MoS ₂ as a co-catalyst to improve the reduction from Fe ³⁺ to Fe ²⁺, the cascade process demonstrates high performance in oxidative degradation of organics ( e.g., 100 mg L ⁻¹ tetracycline within 100 min). The in situ generated H ₂O ₂, with a yield as high as 1575 μmol g ⁻¹ h ⁻¹ in air-saturated methanol solution (75 vol%), accounts for 43.5% of the total degradation efficiency. The current system represents an effective solution to the challenges in the traditional Fenton reaction, holding great potential for organic pollutant degradation in wastewater.