Investigation on mos2 g C3N4 nanocomposites photocatalytic industrial dye degradation and cu2o crystal facets antibacterial activities

Abstract

Two-Dimensional (2D) semiconductors are emerging materials for environmental pollutant degradation due to their unique physical and chemical properties including high specific surface area, tunable bandgap energy, high electron mobility, and quantum confinement effect. The 2D semiconductors have a wide range of absorbance bands (from UV to visible region), narrow bandgap energy, and high luminescence properties. The metal-free graphitic carbon nitride (g-C3N4) is a potential candidate in photocatalytic applications because of its suitable bandgap energy of 2.7 eV, high surface area, and chemical stability. The 2D/2D g-C3N4-based semiconductor heterojunction is the most viable method to meet all the essential requirements including high visible light absorption, high reduction and high oxidation potential, and reduced recombination process for industrial textile dye degradation under natural sunlight. The g-C3N4 nanosheets and 2D/2D MoS2 (5%, and 10%)/g-C3N4 nanocomposites with lateral sizes of 20 and 150 nm are synthesized through a two-step self-assembly method. The structural and morphological properties of the MoS2/g-C3N4 heterojunction were evaluated by XRD and HRTEM analysis. The small quantity of MoS2 improves the visible light absorption of g-C3N4 and develops strong interface contact to form 2D/2D MoS2/g-C3N4 nanocomposites. The effect of 2D/2D MoS2/g-C3N4 results in a red-shifted absorption peak from 460 to 510 nm and a decrease in the bandgap energy from 2.7 to 2.5 eV. Also, its photoluminescence emission intensity is quenched (30%) compared to g-C3N4, confirming the efficient separation of the photogenerated electron-holes pair. Remarkably, the complete (100%) methylene blue (MB) degradation is achieved by 5%MoS2/g-C3N4 nanocomposites within 60 min under natural sunlight. newline