Exfoliated and reorganized graphite oxide on titania nanoparticles as an auxiliary co-catalyst for photocatalytic solar conversion

Abstract

The hybrid of graphite oxide (GO)/TiO₂ was prepared through the spontaneous exfoliation of bulky graphite oxide and reorganization with TiO₂ nanoparticles as a solar conversion and hydrogen-generating photocatalyst. GO/TiO₂ showed enhanced activities for both photocurrent generation (in an electrode form) and hydrogen production (in a slurry form) than those of bare TiO₂ under UV light irradiation. The enhanced photocatalytic activity of GO/TiO₂ is ascribed to the ability of graphitic layers in accepting and transporting electrons from excited TiO₂, promoting the charge separation. When GO was hybridized with platinized TiO₂ (Pt/TiO₂), it showed a marked synergistic effect for the photocatalytic hydrogen production compared with GO/TiO₂ and Pt/TiO₂. This indicates that the cheap and abundant carbon material can be a good candidate for an electron attracting reservoir and an auxiliary co-catalyst for the photocatalytic hydrogen production.