Microwave synthesis of CMF@FexOy-CN: a highly dispersible magnetically recyclable photocatalyst for efficient Rh B degradation

Polluted water poses a significant threat to human health and ecological balance, necessitating the development of efficient and cost-effective water purification technologies. This study synthesized a composite photocatalytic material (CMF@Fe_xO_y-CN) using a microwave radiation synchrotron cooling technique. This material incorporates iron oxide-doped g-C₃N₄ and in-situ micro-fibrillated cellulose, exhibiting high dispersion stability and magnetic recyclability. The material demonstrates a bandgap energy (E_g) of 2.69 eV. Remarkably, 25 mg/20 mL of CMF@Fe_xO_y-CN (with 40 wt% Fe_xO_y-CN loading) achieved a 97.9 % degradation of Rhodamine B (Rh B) within 1 h. Even after 10 cycles, the degradation efficiency remained high at 89.4 %. The superoxide radical (·O₂⁻) played a critical role in Rh B degradation, facilitated by the stable dispersion of CMF. The issue of low photocatalytic efficiency, often caused by poor dispersion of photocatalysts, was addressed through the in-situ micro-fibrillation of cellulose, offering a green and economical solution. This study provides a theoretical foundation for applying photocatalysis in water purification.