Synergetic intimate interface contacts of 2D/1D S-g-C₃N₄/Co-NiS heterojunction with spatial charge separation for boosting photodegradation of MB and inactivation of pathogens under visible light irradiation

The constricted visible light harvesting and undesirable rapid recombination of photogenerated e^- and h⁺ set enormously hinder the activity of the photocatalysts. In this work, we design and develop two-dimensional/one-dimensional (2D/1D) S-g-C₃N₄/Co-NiS heterojunction with intimate heterointerface contact by self-assembly technique. The fast electron transportation of 2D S-g-C₃N₄ nanosheets (NSs) and the well-matched energy levels of bare S-g-C₃N₄ and 5% Co-NiS nanorods (NRs) cooperative support the transportation and separation of photo-carriers at the heterointerface of S-g-C₃N₄/Co-NiS. The as-fabricated samples were evaluated EDX, SEM, UV–vis, XRD, TEM, FTIR, XPS, BET, PL and transient photocurrent. Moreover, this well-defined construction boosts sunlight harvesting and exhibits a large surface area. Benefiting from the intimate coupling and structural features, the 20% S-g-C₃N₄/Co-NiS heterojunction attains a noteworthy photocatalytic methylene blue (MB) degradation rate of 100%, considerably improved than that of bare NiS (34%), 5% Co-NiS (57%) and pristine S-g-C₃N₄ (31%). Concurrently, the photocorrosion of bare S-g-C₃N₄ was suppressed by simultaneous integrating with NiS and engineering with cobalt, which was demonstrated through a chemical stability test with 6 consecutive experimental tests. Such outstanding enrichment in photocatalytic activity and chemical stability was primarily attributed to boosting spatial charge separation and synergistic effects of the 20% 2D/1D S-g-C₃N₄/Co-NiS nanocomposites (NCs). Antibacterial performance of 20% 2D/1D S-g-C₃N₄/Co-NiSNCs against 4 infectious species was evaluated in visible light radiance. Our results emphasize the great importance of the efficacious heterointerface blend of 2D/1D S-g-C₃N₄/Co-NiS NCs as a promising photocatalyst scheme for enhanced photocatalytic degradation of dye and disinfection of pathogens.