Abstract (EN):
Hybrid photocatalysts containing different amounts of carbon nanotubes (CNTs) and TiO2 were synthesized by a one-pot oxidation/hydrothermal route and used for hydrogen production from aqueous solutions of methanol and glycerol under UV-LED irradiation. Platinum nanoparticles (1 wt%) were used as co-catalysts. Different techniques, namely X-ray diffraction, transmission electron microscopy, photoluminescence, electrochemical impedance, diffuse reflectance UV-vis spectroscopy, thermogravimetry and N-2 adsorption were used to characterize the prepared materials. The presence of both CNTs and Pt has a great influence on the photocatalytic activity of CNT-Pt/TiO2 nanocomposites. The presence of CNTs extend the photo-response of TiO2 to the visible region, narrow its bandgap energy, enhance the charge mobility and reduce the electron/hole recombination. The hybrid material loaded with 1 wt% of CNT (1%CNT-Pt/TiO2), displayed the highest photoactivity for hydrogen production under UV-LED (384 nm) irradiation using both methanol and aqueous glycerol solutions, with 2327 and 2091 mu mol g(-1) of H-2 produced at the end of 2 h of irradiation, respectively. Also, this material showed excellent photostability during at least three cycles.
Idioma:
Inglês
Tipo (Avaliação Docente):
Científica
Nº de páginas:
7