Electrochemically Li-intercalated TiO₂ nanoparticles for High performance photocatalytic production of hydrogen

Alkali metal ion intercalation into TiO₂ photocatalysts is a well-known method for obtaining enhanced photocatalytic properties. Herein, an effective electrochemical lithiation method is proposed for the synthesis of lithium-intercalated TiO₂ nanoparticles (NPs) suitable for high performance photocatalytic production of hydrogen. The electrochemical lithiation of TiO₂ induces partial reduction of Ti ions in the crystal lattices, which introduces additional energy states within the band edge of TiO₂, resulting in the improved optical properties. Consequently, Li-intercalated TiO₂ NPs exhibit almost 60-times improved hydrogen generation activity under both UV and visible light exposure compared to those of commercial TiO₂ NPs (P25).