Harnessing Visible Light: MXene/g-C3N4/WO3/NiO Nanocomposite for Rapid Degradation of Tetracycline

Abstract

The ubiquity of antibiotics such as tetracycline (TC) in aquatic environments poses serious global health issues due to their persistence and ability to enhance antimicrobial resistance. This paper presents MXene/g-C₃N₄/WO₃/NiO (MGWN), prepared by a simple hydrothermal route, which was evaluated for its performance as a photocatalyst in the photodegradation of TC under visible light. The coupling of metal oxides (WO₃ and NiO) with carbon-based materials (MXene and g-C₃N₄) promotes photocatalytic activity through enhanced light absorption and charge separation. In-depth characterization using FT-IR, XRD, UV-DRS, FE-SEM, HR-TEM, and EDAX validated the development of textured nanostructure with particle sizes in the range 10–35 nm and a band gap of 2.84 eV. Photocatalytic activity tests demonstrated that MGWN exhibited a remarkable TC (5 ppm) removal rate of 99.35% within 120 min, adhering closely to pseudo-first-order kinetics. The apparent rate constant (k) was calculated to be 1.55 × 10^–2 min^–1 (R² 0.9931), indicating a substantial rate of reaction. Further stability and reusability assessments revealed that the MGWN nanocomposite maintained over 90% photocatalytic efficiency after five consecutive cycles, reinforcing its potential for sustainable wastewater treatment applications. The findings highlight the MGWN nanocomposite as an effective and stable photocatalyst for removing persistent organic pollutants, paving the way for future advancements in environmental remediation technologies.