Hydrogenated anatase: strong photocatalytic dihydrogen evolution without the use of a co-catalyst

Angew Chem Int Ed Engl. 2014 Dec 15;53(51):14201-5. doi: 10.1002/anie.201408493. Epub 2014 Oct 19.

Abstract

The high-pressure hydrogenation of commercially available anatase or anatase/rutile TiO2 powder can create a photocatalyst for H2 evolution that is highly effective and stable without the need for any additional co-catalyst. This activation effect cannot be observed for rutile; however, for anatase/rutile mixtures, a strong synergistic effect can be found (similar to results commonly observed for noble-metal-decorated TiO2). EPR and PL measurements indicated the intrinsic co-catalytic activation of anatase TiO2 to be due to specific defect centers formed during hydrogenation. These active centers can be observed specifically for high-pressure hydrogenation; other common reduction treatments do not result in this effect.

Keywords: TiO2; co-catalyst; hydrogenation; titanium(III); water splitting.