Fabrication of Heterostructured Fe2 TiO5 -TiO2 Nanocages with Enhanced Photoelectrochemical Performance for Solar Energy Conversion

Abstract

Photocatalysts with well-designed compositions and structures are desirable for achieving highly efficient solar-to-chemical energy conversion. Heterostructured semiconductor photocatalysts with advanced hollow structures possess beneficial features for promoting the activity towards photocatalytic reactions. Here we develop a facile synthetic strategy for the fabrication of Fe₂ TiO₅ -TiO₂ nanocages (NCs) as anode materials in photoelectrochemical (PEC) water splitting cells. A hydrothermal reaction is performed to transform MIL-125(Ti) nanodisks (NDs) to Ti-Fe-O NCs, which are further converted to Fe₂ TiO₅ -TiO₂ NCs through a post annealing process. Owing to the compositional and structural advantages, the heterostructured Fe₂ TiO₅ -TiO₂ NCs show enhanced performance for PEC water oxidation compared with TiO₂ NDs, Fe₂ TiO₅ nanoparticles (NPs) and Fe₂ TiO₅ -TiO₂ NPs.

Keywords: Fe2TiO5; TiO2; heterostructures; metal-organic frameworks; nanocages.