Preparation of Mesoporous Bicrystalline N-Doped TiO2 Nanomaterials for Sustainable RhB Degradation under Sunlight

Abstract

N-doped titanium dioxide (N/TiO2) nanomaterials were successfully prepared using titanium butoxide and guanidinium chloride using the simple sol-gel method. The significance of the annealing gas environment (air, argon, or nitrogen) on their physicochemical and photocatalytic degradation properties was investigated. Indeed, the gas type governed the crystal/phase nature from monophase anatase with a low crystallinity to dual-phase anatase/rutile with a higher crystallinity. Moreover, results revealed that the introduction of N in the TiO2 matrix led to a red shift towards visible-light, narrowed the bandgap (2.35 eV), and suppressed recombination. Nobly, the N/TiO2 prepared in air demonstrated the highest RhB degradation performance (99%) with the highest rate constant (0.0158 min−1), which was twice faster than the undoped TiO2.