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

Abstract 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.