Controlled Synthesis of TiO2 Nanostructures: Exceptional Hydrogen Production in Alcohol-Water Mixtures over Cu(OH)2–Ni(OH)2/TiO2 Nanorods

Abstract

Development of non-noble metal photocatalysts for hydrogen (H2) generation from renewables is important towards cost effective technology. Titania nanorods with different phase compositions and surface areas were fabricated by calcination of hydrogen titanate (H2Ti3O7) precursors obtained by treating P25 (TiO2) hydrothermally in 10 M NaOH and followed by HCl washing. Subsequently the copper and nickel hydroxides were co-deposited over TiO2 nanorods and used to generate H2 from alcohol-water mixtures under UV light. Among the synthesized materials, the optimized photocatalyst 0.8Cu(OH)2-0.2Ni(OH)2/TNR130-400 showed very high H2 production rates that are 26.6 mmol h−1g−1 in 20 vol.% ethanol-water mixture and 35.1 mmol h−1g−1 in 5 vol.% glycerol-water mixtures. The amount of this H2 production is even higher than obtained from noble metal supported TiO2 photocatalysts. This exceptional photocatalytic H2 production is attributed to the high synergism among nanords mophology of support and in situ formation of Cu and Ni exclusively in metallic states during photoreactions.