Molecular Hydrogen Formation from Photocatalysis of Methanol on Anatase-TiO₂(101)

Photocatalysis of methanol (CH₃OH) on anatase (A)-TiO₂(101) has been investigated using temperature programmed desorption (TPD) method with 266 nm light at low surface temperatures. Experimental results show that CH₃OH adsorbs on the A-TiO₂(101) surface predominantly in molecular form, with only a small amount of CH₃OH in dissociated form. Photocatalytic products, formaldehyde (CH₂O) and methyl formate (HCOOCH₃), have been detected under 266 nm light irradiation. In addition to H₂O formation, H₂ product is also observed by TPD spectroscopy. Experimental results indicate that H₂ product is formed via thermal recombination of H-atoms on the BBO sites from photocatalysis of CH₃OH on the A-TiO₂(101) surface, and H₂ production on the A-TiO₂(101) surface is significantly more efficient than that on the rutile (R)-TiO₂(110) surface.