Dual-function Cameroonian clay-supported ZnO and TiO₂ photocatalysts for ibuprofen mineralization and bacterial inactivation

The increasing presence of pharmaceuticals, such as ibuprofen, in wastewater poses significant environmental and public health challenges, particularly in developing regions. In this study, we developed photocatalytic materials by doping natural Cameroonian clay with ZnO and TiO₂ to achieve efficient ibuprofen mineralization and bacterial inactivation under ultra-violet (UV) light. Characterization confirmed the successful integration of semiconductors into the clay matrix, which enhanced the surface area to 325 m²/g for TiO₂-based composites. Under UVA irradiation (1.2 mW/cm²), the Cu-doped TiO₂/clay composite achieved 48 % ibuprofen mineralization, measured by Total Organic Carbon (TOC) reduction, within 4 h, while ZnO-based composites reached up to 23 % under similar conditions. Antibacterial tests demonstrated complete inhibition of Shigella spp., total coliforms, and faecal streptococci at a catalyst dosage of 1 g/L under UVA, highlighting the dual functionality of the materials. These low-cost, locally sourced photocatalysts show promise for integrated pharmaceutical and microbial removal in decentralized wastewater treatment systems, offering a sustainable solution for water purification in resource-limited settings. • Synthesized and characterized clay-based photocatalysts doped with ZnO and TiO₂ using natural Cameroonian smectite. • Achieved up to 48 % ibuprofen mineralization under UVA in 4 h, confirmed by Total Organic Carbon (TOC) analysis. • Demonstrated antibacterial activity against Shigella spp., total coliforms, and faecal streptococci at 1 g/L under UVA. • Developed a low-cost, eco-friendly material from local resource for sustainable wastewater treatment in developing regions. • Dual functionality for simultaneous pharmaceutical degradation and microbial inactivation in decentralized systems.