Green approach and ease synthesis of C/N-codoped TiO2 nanocrystals for photodegradation of endocrine

Carbon species and nitrogen-codoped anatase TiO2 (C/N-codoped TiO2) nanocrystals with uniform particle size and high crystallinity were synthesized, employing hexamethylenetetramine (HMTA) as a nitrogen and carbon source throughout solvothermal reaction of TiCl4 and HMTA at different contents (0.5 g, 1 g, 1.5 g, and 2 g HMTA). The synthesized photocatalysts were assessed by photocatalytic degradation of resorcinol as a probe of potent endocrine-disrupting chemicals (EDCs) compared with commercial P-25 photocatalyst. Raman spectra and XRD results confirmed that the obtained C/N-codoped TiO2 is anatase TiO2 phase with 10-20 nm nanocrystallite sizes. For resorcinol photo-oxidation in aerated aqueous solution, C/N-codoped TiO2 nanocrystals synthesized at 0.5 g HMTA (H0.5) showed the superior photocatalytic efficiency among all synthesized photocatalysts. H0.5 photocatalyst exhibited the outstanding photocatalytic performance, which is 1.2 and 2 times greater than that of commercial P-25 and pure TiO2. In addition, the rate constant of the H0.5 sample was enhanced 7.5 and 3 times than that of commercial P-25 and pure TiO2, respectively. The C/N-codoped TiO2 nanocrystals achieved high photocatalytic efficiency of up to 96% within 90 min. In contrast, the photocatalytic efficiency based on the commercial P-25 was 54%. The photocatalytic efficiency of C/N-codoped TiO2 was considerably enhanced, owing to its increase of photogenerated charge separation rate, smaller crystal size, narrower bandgap energy, and stronger light harvesting in wide visible region. Detailed mechanistic and kinetic studies through photodegradation of resorcinol in water were addressed.