g-C3N4/TiO2/CuO S-scheme heterostructure photocatalysts for enhancing organic pollutant degradation

Abstract The photocatalytic degradation of organic impurities is a promising eco-friendly system for wastewater treatment. Herein, the CuO coupled g-C3N4/TiO2 ternary heterostructure nanocomposites (NCs) were effectively synthesized by facile hydrothermal strategy. The powder XRD, FT-IR, HR-TEM, FE-SEM with EDX, high-resolution XPS, UV–Vis DRS, BET and PL spectra analyses confirm the effective construction of g-C3N4/TiO2/CuO heterostructure composite photocatalysts (PCs). The g-C3N4/TiO2/CuO composite PCs displays photocatalytic enhanced performance for rhodamine B (RhB) dye decomposition than to pristine g-C3N4 PCs under simulated sunlight exposure. At optimum photocatalytic test conditions, the RhB dye was degraded (∼90.3%) within 120 min of light irradiation. No noticeable loss of photo-activity appeared after the five-succeeding recycle test. Moreover, the proposed S-scheme charge transfer mechanism based on scavenger's tests, the photocatalytic enhanced performance of optimum g-C3N4/TiO2/CuO composite PCs is ascribed to the synergistic close interfacial contact, wide visible-light fascination, improved charge separation rate and actively inhibited the recombination rates of efficient e−/h+ pairs relatively.