In situ green oxidation synthesis of Ti3+ and N self-doped SrTiOxNy nanoparticles with enhanced photocatalytic activity under visible light

摘要

A simple in situ green oxidation synthesis route was developed to prepare Ti ~(3+) and N self-doped SrTiO _( x ) N _( y ) nanoparticles using TiN and H _(2) O _(2) as precursors. X-ray diffraction (XRD), scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) were used to characterize the crystallinity, structure and morphology. X-ray photoelectron spectroscopy (XPS) tests confirmed the presence of Ti ~(3+) and N in the prepared SrTiO _( x ) N _( y ) nanoparticles. The resultant nanoparticles were shown to have strong absorption from 400 to 800 nm using UV-vis diffuse reflectance spectroscopy (UV-vis DRS). The formation mechanism of the Ti ~(3+) and N self-doped SrTiO _( x ) N _( y ) nanoparticles was also discussed. Under visible light irradiation, the obtained Ti ~(3+) and N self-doped samples showed higher photocatalytic activity for the degradation of the model wastewater, methylene blue (MB) solution. The most active sample T-130-Vac, obtained at 130 °C under vacuum, showed a 9.5-fold enhancement in the visible light decomposition of MB in comparison to the commercial catalyst nano-SrTiO _(3) . The sample also showed a relatively high cycling stability for photocatalytic activity.