A Facile In Situ Hydrothermal Etching Method to CaTiO3/TiO2 Heterostructure for Efficient Photocatalytic N2 Reduction

Photocatalytic nitrogen fixation for the synthesis of ammonia is an important and attractive method to N2 turning into other compounds. The development of compact heterostructure photocatalysts is crucial for efficient solar energy conversion. Here, composite was obtained by simple in situ hydrothermal etching of the reduced TiO2 nanospheres with saturated calcium hydroxide solution. CaTiO3/TiO2 heterostructure composite can adsorb, activate and convert N2 to ammonia by using its close contact interface. Under simulated sunlight irradiation, CaTiO3/TiO2 composite greatly enhanced the photocatalytic N2 reduction performance. Compared with pure CaTiO3, the efficiency of 0.3-T–C heterostructure in synthesizing NH3 under visible light was 1.88 times higher than that of pure CaTiO3 (59.17 μmol·g−1·h−1) The excellent photocatalytic performance of CaTiO3/TiO2 is attributed to the close structure between CaTiO3 and TiO2, which promotes the separation of photogenerated charges and provides more active sites. This study provides a basic idea for the rational design of highly efficient heterogeneous photocatalysts to achieve excellent photocatalytic performance for N2 reduction.