Constructing direct Z-scheme heterojunctions of defective MoS2-v on carbon nitride nanotubes for high-performance hydrogen peroxide production and iron-free photo-Fenton-like reactions over a wide pH range

In this work, we first applied molybdenum disulfide with S vacancy (MoS2-v) /carbon nitride nanotube (TCN) composite (MoS2-v/TCN) to drive the iron-free photo-Fenton-like reaction. The well-designed band structure enables MoS2-v/TCN to construct direct Z-scheme heterostructures, realizing the rapid separation of photoinduced-e(-) and h(+), and effectively improving the photocatalytic efficiency of MoS2-v/TCN. DFT calculation showed that Z-scheme heterojunction greatly reduced the energy barrier for generating *OOH and *HO2-, affording MoS2/TCN high performance and stability toward H2O2 generation (pure water: 254.8-269.9 mu mol center dot g(-1)center dot h(-1), 10 % isopropanol: 1879 mu mol center dot g(-1)center dot h(-1)) over a wide pH range (3-9). The photoinduced-e(-) and Mo4+ on the surface of MoS2-v/TCN rapidly converted H2O2 in situ to strong oxidizing center dot OH, realizing the efficient degradation of organic pollutants and rapid inactivation of bacteria. This work provides a new approach to solving the technical bottlenecks in traditional Fenton oxidation via synthesizing multifunctional heterojunction for in situ H2O2 generation and activation.