Low-Temperature Microwave-Assisted Hydrothermal Synthesis of Pb<sub>2</sub>Ti<sub>2</sub>O<sub>5.4</sub>F<sub>1.2</sub> Photocatalyst for Improved H<sub>2</sub> Evolution under Visible Light
Kenta Aihara, Ryusuke Mizuochi, Megumi Okazaki, Shunta Nishioka, Shuhei Yasuda, Toshiyuki Yokoi, Fumitaka Ishiwari, Akinori Saeki, Miki Inada, Kazuhiko Maeda
Abstract
High Resolution Image Download MS PowerPoint Slide Mixed-anion compounds are promising candidates as visible-light-driven photocatalysts; however, their synthesis is generally difficult compared to that of their ordinary single-anion counterparts such as oxides. This difficulty is often an obstacle in maximizing the performance of mixed-anion photocatalysts. In this work, Pb 2 Ti 2 O 5.4 F 1.2 particles having a well-defined octahedral shape were successfully synthesized by a microwave-assisted hydrothermal (MHT) method at 473 K. The MHT-Pb 2 Ti 2 O 5.4 F 1.2 exhibited a greater specific surface area and improved hydrophilicity compared with its analogue synthesized by a conventional solid-state reaction (SSR). Compared with the SSR-Pb 2 Ti 2 O 5.4 F 1.2, the MHT-Pb 2 Ti 2 O 5.4 F 1.2 exhibited 6-fold greater activity toward visible-light H 2 evolution from water. A postheating treatment of the MHT-derived material in air at 573 K further improved its activity 3–4 fold. The optimized MHT-Pb 2 Ti 2 O 5.4 F 1.2 also achieved a nonsacrificial H 2 evolution in the presence of a reversible electron donor.