MWNT–TiO 2:Ni composite catalyst: A new class of catalyst for photocatalytic H 2 evolution from water under visible light illumination

Abstract

Multi-walled carbon nanotube, TiO 2 and Ni composite catalysts (MWNT–TiO 2:Ni) were prepared by a modified chemical vapor deposition. The nanoscaled composite materials were extensively characterized by TG, SEM, Raman and UV–vis spectra. The photoactivity of the catalyst for H 2 evolution was investigated in the presence of methanol sacrificial reagent under visible light illumination. The rate of H 2 evolution was 38.1 μmol/h at a weight ratio of MWNT/TiO 2 equal to 4.4%. The experimental results were rationalized by assuming that MWNTs serve as photosensitizer, synergetic with metallic Ni, greatly enhancing the activity of visible light-responsive photocatalyst.