Construction of flake ball-shaped Bi2WO6 embedded on phenyl functionalized g-C3N4 nanosheet for efficient degradation insight of colorless pollutants and its biological application.

A facile solvent-free solid-state method was adapted to synthesize the spherical-shaped Bi2WO6 engraved on phenyl-doped g-C3N4 nanosheet, i.e., Bi2WO6/Ph-gC3N4 (or BPCN) composites with varying weights of Bi2WO6. Several spectral analyses were used to characterize all the synthesized nanomaterials. The synthesized photocatalyst showed good absorption under visible light as confirmed by UV-visible DRS analysis. Morphological analyses like SEM and TEM determine the successful fabrication of binary heterocomposite. Further, the elements available in the fabricated binary nanocomposite were confirmed by XPS. The photocatalyst was used for the aerobic photocatalytic degradation of a few colorless pollutants like bisphenol A (BPA, 30 mg L-1), a microplastic constituent, and tetracycline (TC, 40 mg L-1), an antibiotic derivative to achieve the impressive results. The less intense PL signal obtained for the 20BPCN heterocomposite reveals the remarkable enhancement in e--h+ pair separation and recombination rate. The quenching study, alkaline terephthalic acid photoluminescence test (TA-PL), and NBT phototransformation study explain the formation of reactive species involved in the decomposition process. An oral cancer cell line (A-254) was tested for the anticancer activity analysis of the 20BPCN photocatalyst. Based on the obtained results, a Z-scheme electron transfer mechanism has been proposed for the photodegradation of model compounds.

Fabrication of Direct Z-Scheme CoNiWO4/Ph-gC3N4 Heterocomposites: Enhanced Photodegradation of Bisphenol A and Anticancer Activity.

Photocatalysis is realized by the design of a visible-light-active catalyst with robust redox capacity and broad absorption. In this study, a series of novel Z-scheme CoNiWO4/Ph-gC3N4 photocatalysts are synthesized to improve their redox property and photocatalytic activity toward broad visible light absorption. An intimate stable heterojunction is made between cobalt-nickel tungstate (CoNiWO4) and phenyl-doped graphitic carbon nitride (Ph-gC3N4), and its physicochemical properties are studied. The bifunctional properties of all of the synthesized materials were assessed by studying the decomposition of bisphenol A (BPA) and methyl orange (MO) dye as model pollutants, followed by an evaluation of their anticancer activity on human lung cancer cell lines. The photocatalyst with 20 wt % CoNiWO4 heterocomposite showed an enhanced response toward the removal of cancerous cells. The synthesized pristine CoNiWO4 and Ph-gC3N4 exhibit well-matched band structures and, hence, make it easier to create a Z-scheme heterocomposite. This may increase the lifetime of photoinduced charge carriers with a high redox power, thereby improving their photocatalytic and anticancer activity. An extensive analysis of the mechanism demonstrates that hydroxyl radicals (•OH) and superoxide radical anions (•O2-) are responsible for the degradation of organic compounds via Z-scheme charge transfer approach. These findings point toward a new route for creating effective Co-Ni tungstate-based direct Z-scheme photocatalysts for various redox processes, particularly the mineralization of resistant organic molecules.