Facile construction of novel ZnO and TiO₂ combined g-C₃N₄ nanocomposite for superior visible-light photocatalytic organic pollutant degradation

ABSTRACT

A novel g-C₃N₄/ZnO-TiO₂ nanocomposite was prepared by facile calcination and hydrothermal assisted route to boost the photocatalytic efficiency of g-C₃N₄. The structural, morphology and optical properties of as-obtained nanocomposites (NCs) were examined by various physicochemical methods such as XRD, FT-IR, FESEM-EDX, HR-TEM, UV-DRS and PL spectra relatively. The as-obtained g-C₃N₄/ZnO-TiO₂ heterojunction NCs displays an optimum efficiency (93.6%) and high photo-degradation rate constant towards the photo-degradation of RhB dye in 75 min under visible-light exposure. Likewise, the synergistic effects on heterostructure strong-coupling interfaces assembly of g-C₃N₄ and TiO₂/ZnO NPs, which facilitates the excellent photo-excited charge separation efficiency, suppressing the recombination rate and also widening the visible-light fascination ability. Hence, the resulting in a prolonged lifetime leading to continuous generation of h⁺ and ^•OH⁻ species which were eventually improved the photo-degradation process. Also, the as-obtained hybrid g-C₃N₄/ZnO-TiO₂ photocatalysts (PCs) revealed superior recycling stability. Moreover, a probable photocatalytic reaction mechanism of the novel PCs was also suggested.

KEYWORDS:

• Photocatalysts
• nanocomposites
• visible-light
• Rhodamine B dye
• recycling stability
• charge transfer

Acknowledgments

The author would gratefully acknowledge the DST-INSPIRE division for providing the INSPIRE fellowship (IF150961). The authors would like to express their gratitude to the Deanship of Scientific Research at King Khalid University, Abha, Saudi Arabia for funding this work through Research Groups Program under grant No. R.G.P/2/110/42.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Declaration

The authors have declared no conflict of interest.

Additional information

Funding

This work was supported by the King Khalid University [R.G.P/2/110/42]; Department of Science and Technology, Ministry of Science and Technology [IF150961].