Low-Temperature Microwave-Assisted Hydrothermal Synthesis of Pb2Ti2O5.4F1.2 Photocatalyst for Improved H-2 Evolution under Visible Light

Mixed-anion compounds are promising candidates as visible-light-drivenphotocatalysts; however, their synthesis is generally difficult comparedto that of their ordinary single-anion counterparts such as oxides.This difficulty is often an obstacle in maximizing the performanceof mixed-anion photocatalysts. In this work, Pb2Ti2O5.4F1.2 particles having a well-definedoctahedral shape were successfully synthesized by a microwave-assistedhydrothermal (MHT) method at 473 K. The MHT-Pb2Ti2O5.4F1.2 exhibited a greater specific surfacearea and improved hydrophilicity compared with its analogue synthesizedby a conventional solid-state reaction (SSR). Compared with the SSR-Pb2Ti2O5.4F1.2, the MHT-Pb2Ti2O5.4F1.2 exhibited 6-foldgreater activity toward visible-light H-2 evolution fromwater. A postheating treatment of the MHT-derived material in airat 573 K further improved its activity 3-4 fold. The optimizedMHT-Pb2Ti2O5.4F1.2 alsoachieved a nonsacrificial H-2 evolution in the presenceof a reversible electron donor.

Automated summary

Mixed-anion compounds are difficult to synthesize compared to ordinary single-anion counterparts, but they have great potential as visible-light-driven photocatalysts. In this study, Pb2Ti2O5.4F1.2 particles with a well-defined octahedral shape were successfully synthesized by a microwave-assisted hydrothermal (MHT) method at 473 K. The MHT-Pb2Ti2O5.4F1.2 showed improved activity for visible-light H-2 evolution compared to its analogue synthesized by a conventional solid-state reaction (SSR). A postheating treatment further enhanced its activity, and the optimized MHT-Pb2Ti2O5.4F1.2 achieved nonsacrificial H-2 evolution in the presence of a reversible electron donor.