Hydrogen Photoproduction from Water-Methanol on Titania Covered with Copper

Article abstract of DOI:10.1007/BF00811463

Hydrogen photogeneration from water-methanol solution was studied on Cu-TiO2 photoactive systems.It was found that Cu-deposit on titania particles could be obtained in situ in a reaction cell.The dispersed copper showed satisfactory good activity (quantum yield 4.3percent) and stability under H2 production conditions.The hydrogen evolution catalytic properties of Cu were also proved in an electrochemical study: a graphite electrode immersed in Cu/TiO2 suspension showed dark cathodic current at about -0.9 V vs.SCE.It was checked in two simple experiments that the reduction of Cu²⁺ by illuminated titania leads to Cu(O) deposited onto semiconductor particles.Using an ion selective electrode it was found that Cu²⁺ reduction was accomplished in 20 minutes.Bigger amounts of copper (>1 wt.percent) were photodeposited on the already existing metal islands.Cu²⁺ preadsorption on titania was small and did not have any influence on the hydrogen evolution activity of Cu/TiO2. 0.5 wt.percent on TiO2 was found as an optimum metal loading. Keywords.Photocatalysis; Copper; Titania.