Long-lived photoinduced charge-carriers in Er3+ doped CaTiO3 for photocatalytic H2 production under UV irradiation

Abstract The incorporation of Er 3+ ions in the CaTiO 3 structure provides an enhanced H 2 photoproduction due to the formation of long-lived charge-carriers in the semiconductor. Nitroblue tetrazolium reaction, photoluminescence and time resolved microwave conductivity techniques were used to investigate the generation of the superoxide species and the lifetime of the charge-carriers. The improved photoactivity has been explained in terms of the dopant agent, finding that phenomena such as a higher concentration of the superoxide radicals, a more efficient separation of the photogenerated charge-carriers, and a slower recombination process take place in the Er 3 + doped CaTiO 3 compared to the undoped CaTiO 3 .