Photocatalytic H2 production with simultaneous wastewater purification over flower-like 1T/2H-MoS2-decorated CNT/CNU isotype heterojunction photocatalyst

Exploring low-cost and earth-abundant photocatalysts to efficiently release H-2 from wastewater is an appealing solution for global energy and environmental issues. Here, we successfully prepared flower-like 1T/2H-MoS2-decorated g-C3N4 (thiourea)/g-C3N4 (urea) (denoted as CNT/CNU) isotype heterojunction photocatalysts via a facile ultrasonic dispersion method and researched the photocatalytic H-2 generation and pollutant degradation performance in oxalic acid (OA) simulated wastewater. The results displayed that 20% 1T/2H-MoS2@CNT/CNU sample exhibited the highest photoreactivity, and the H-2 release rate was 1563.32 mu molg(-1)h(-1), which was about 96 times higher than the CNT/CNU. Meanwhile, it also showed the highest total organic carbon (TOC) removal rate of 67.5%. The increased photoreactivity of nanocomposites can be ascribed to the double-interface system to effectually improve the separation of photoinduced charges. Additionally, the experimental results further confirmed that the loading of flower-like 1T/2H-MoS2 could provide abundant active sites as well as expand the visible-light absorption range. Significantly, photoelectrochemistry measurements and density functional theory (DFT) calculations also confirmed that 1T/2H-MoS2 cocatalysts accelerated the charge migration. On this basis, the mechanism of 1T/2H-MoS2@CNT/CNU promoting hydrogen production and synergistic OA degradation was proposed. This research presents a prospective idea for the utilization of waste water and the simultaneous production of clean energy.