Controlled synthesis of CaTiO3:Ln3+ nanocrystals for luminescence and photocatalytic hydrogen production
Bifunctional CaTiO3:Ln3+ (Ln Eu and Er) nanocrystals were prepared via a facile method followed by calcination in air. The as prepared CaTiO3:Ln3+ nanocrystals exhibited bifunctional performance for both photoluminescence and photocatalytic hydrogen production. As a phosphor powder, the luminescence properties of CaTiO3:Ln3+ nanocrystals could be controlled by doping with different Ln3+ ions. They showed very stable luminescence properties and a much higher quenching concentration due to the scheelite related structure of CaTiO3, which was up to 17% (Eu doping) As a photocatalyst, the CaTiO3:Ln3+ nanocrystals exhibited a higher activity for hydrogen production under ultraviolet light irradiation. The CaTiO3:Er3+ nanocrystals displayed the highest photocatalytic activity of up to 461.25 mmol h 1, which was higher than that of CaTiO3:Eu3+ nanocrystals and pure CaTiO3. The results indicated that incorporation of Ln3+ ions benefits electron transfer as well as the reduction of the band gap of the CaTiO3 photocatalyst.