Enhanced photoelectron transport with favorable interfacial contact in 2D/3D SnIn4S8 nanosheet/Bi2MoO6 microsphere composite triggering efficient H2O2 generation and MO degradation

Abstract

Solar light driven photocatalytic in-situ synthesis of H2O2 and treatment of water pollutants are the sustainable, efficient and carbon-free technologies. However, the development of an effective multifunctional photocatalyst is the major challenge to advance the practical application of this technology. In this paper, a novel 2D/3D SnIn4S8 nanosheet/Bi2MoO6 microsphere (BMOSIS) composite for the photocatalytic H2O2 generation in the air without adding sacrificing agents and the photodegradation of methyl orange (MO) was synthesized via an ultrasonic self-assembly method. The enhanced photocatalytic activities were contributed to the intimate interfacial contacts favor for the efficient charge separation, enhanced visible light capture ability for efficiently improving optical quantum yield, and increased surface area conducive to surface photocatalytic reactions. The optimized sample BMOSIS2 possessed the highest visible-light photocatalytic H2O2 generation yield (66.33 μM) in 150 min, which was 27.07 and 5.69 times higher than those of pure Bi2MoO6 and SnIn4S8. In addition, sample BMOSIS2 also showed the highest degradation rate constant (0.0260 min−1), which was 10.40 and 2.03 times that of the original Bi2MoO6 (0.0025min−1) and SnIn4S8 (0.0128min−1), respectively. The mechanisms for the photocatalytic H2O2 production and photodegradation of MO were also proposed. This work will offer a new strategy for constructing dual-functional photocatalyst for in-situ photocatalytic H2O2 generation and wastewater treatment.