Z-scheme Ti₃C₂ MXene@CeO₂ heterostructures for efficient and secondary pollution free photodegradation of pharmaceutical drug

The increasing concentrations of emerging organic contaminants (EOCs) in wastewater threaten human health and the environment. Their complex structures, low concentrations, and conversion into secondary metabolites challenge current remediation techniques. This study presents the Z-scheme Ti₃C₂ MXene@CeO₂ (MX@CeO₂) heterostructures, synthesized by a facile in-situ sonochemical method, aimed at enhancing photocatalytic mineralization of highly toxic Doxorubicin (DOX) drug. Our findings reveal that the unique surface and structural properties of Ti₃C₂ MXene facilitated the effective nucleation and growth of the CeO₂. The growth mechanisms involved the adsorption of Ce atoms through negatively charged functional groups, and anchoring to surface defects and vacancies in Ti₃C₂ MXene. The formation of intimate interfacial heterojunctions between Ti₃C₂ MXene and CeO₂ not only facilitated the charge separation and utilization but also improved the photostability, thereby improving the catalytic performance of the composite. Photodegradation experiments demonstrated 96% removal of DOX within 240 ​min of visible light exposure. Moreover, high-performance liquid chromatography analysis confirmed the complete mineralization of DOX. The post degradation analysis revealed the minimal cytotoxicity induced by photodegraded residues. The stability and sustained catalytic efficiency of MX@CeO₂ in degrading DOX into non-toxic residues position such Z-scheme heterostructures as promising candidates for long-term remediation of EOCs.