Self-assembled ionic liquid synthesis of nitrogen-doped mesoporous TiO2 for visible-light-responsive hydrogen production

• Published in: International journal of hydrogen energy 2017-09, Vol.42 (38), p.24006-24013
• Main Authors: Liu, Shou-Heng, Tang, Wen-Ting, Lin, Wei-Xing
• Format: Article
• Language: English
• Subjects: Hydrogen generation; Mesoporous structure; N-containing ionic liquid; N-doped; Visible-light-driven
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2017.08.009

Nitrogen-doped mesoporous TiO2 has been synthesized by a simple solvent evaporation-induced self-assembly method using a nitrogen-containing ionic liquid concurrently as a nitrogen source and mesoporous template. After being evaporated and subsequently calcined at various temperatures (300–900 °C), the synthesized samples were thoroughly characterized by X-ray diffraction (XRD), Raman, small-angle X-ray scattering patterns (SAXS), N2 adsorption-desorption isotherms, X-ray photoelectron (XPS) and UV–Vis diffuse reflectance (UV–Vis DR) spectroscopies. The obtained results suggest that the calcination temperature greatly influences the crystallization of TiO2, formation of mesoporous structure, specific surface area and N-doping amounts. Among the fabricated photocatalysts, the samples calcined at 600 °C exhibit superior photocatalytic performance for hydrogen production in water/methanol solution under visible light illumination if compared to other synthesized samples and commercial TiO2 (Degussa P25). The finding is possibly due to the synergy of more N-doping amounts on the well-defined mesoporous TiO2 with highly anatase crystal phase and moderate surface area in the catalysts. •A facile route was developed to synthesize N-doped mesoporous TiO2.•Visible-light photoactivity of the samples was highly surpassing than that of P25.•Calcined temperature greatly influences the properties of N-doped mesoporous TiO2.