Carbon, nitrogen co-doped TiO2 nanoparticles via sol-gel route: An approach for chlorpyrifos degradation

The photocatalytic degradation of wastewater is the most promising environmental remediation. This study focused on chlorpyrifos as a model pollutant due to its widespread use as an organophosphate insecticide. Carbon and nitrogen co-doped titanium dioxide nanoparticles (C, N-TiO 2 NPs) were synthesized using a sol-gel method, employing titanium isopropoxide, urea, and carboxymethylcellulose as titanium, nitrogen, and carbon precursors, respectively. The C, N-TiO 2 NPs were characterized using X-ray diffraction (XRD), photoluminescence (PL) spectroscopy, UV-visible diffuse reflectance spectroscopy, and high-resolution transmission electron microscopy (HRTEM) for the optical, chemical and physical characteristics. Analytical results from XRD and HRTEM revealed anatase-phase structures with a reduced bandgap energy of 2.95 eV. Compared to pure anatase TiO 2 , the synthesized C, N-TiO 2 NPs exhibited slower electron-hole pair recombination, according to PL analysis. Under solar light irradiation, an optimal catalyst dosage of 0.12 g achieved 90% chlorpyrifos breakdown at 8 ppm concentration and 62.1% mineralization degree, with superoxide radicals (•O 2 - ) as the dominant ROS. The photocatalyst exhibited remarkable reusability, achieving 79.5% removal of chlorpyrifos over five cycles during photodegradation processes. Thus, this study creates TiO 2 NPs doped with carbon and nitrogen as an effective photocatalyst for wastewater treatment. • The creation of visible light-activated C, N-TiO 2 photocatalyst by sol-gel method • The synergistic effect of C and N doping improves its photocatalytic performance • Enhanced optical and photocatalytic photocatalyst boost chlorpyrifos degradation • •O 2 - plays a key role in the degradation mechanism of chlorpyrifos • Great reusable C, N-TiO 2 photocatalyst for wastewater treatment applications