Synthesis of N-doped TiO2 nanoparticles with enhanced photocatalytic activity for 2,4-dichlorophenol degradation and H2 production

Nitrogen-doped titanium dioxide (N-TiO2) nanoparticles were prepared using a modified sol-gel method. The as-prepared nanoparticles were characterized by state-of-the-art techniques for their optical, structural and morphological properties. The crystallite size, surface area and bandgap energy of reference TiO2 and N-TiO2 nanoparticles were found to be 16.1 and 10.9 nm, 83.6 and 131.8 m2 g−1 and 3.23 and 2.89 eV, respectively. The photocatalytic activities, in terms of 2,4-dichlorophenol (2,4-DCP) degradation, of reference TiO2 and N-TiO2 were found to be 46.9 and 65.4% at 120 min of treatments under UV light irradiation and 21.5 and 77.6% at 240 min of treatment under visible light irradiation, employing 153.4 µM 2,4-DCP, 1 g L−1 photocatalyst dosage, and pH 5.6. Interestingly, considerable H2 production rate (i.e., 386 μmol h−1 g−1) was observed for visible/N-TiO2 system in presence of 0.2 wt % Pt. The study revealed that visible/N-TiO2 photocatalytic system can be used as an economically viable technology for environmental sustainability.