Fabrication of Heterostructured Fe2TiO5-TiO2 Nanocages with Enhanced Photoelectrochemical Performance for Solar Energy Conversion

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 Fe2TiO5-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 Fe2TiO5-TiO2 NCs through a post annealing process. Owing to the compositional and structural advantages, the heterostructured Fe2TiO5-TiO2 NCs show enhanced performance for PEC water oxidation compared with TiO2 NDs, Fe2TiO5 nanoparticles (NPs) and Fe2TiO5-TiO2 NPs.