羰基合成与选择氧化国家重点实验室（OSSO）知识库

The coupling of semiconductor photocatalysts with graphene quantum dots (GQDs) has been proven to be an effective strategy to enhance the photocatalytic and photoelectrical conversion performances of the resulted composites; however, the preparation of semiconductor/GQDs composites usually involves several time-inefficient and tedious post-treatment steps. Herein, we present a facile one-step hydrothermal route for the preparation of GQDs coupled TiO₂ (TiO₂/GQDs) photocatalysts using 1,3,6-trinitropyrene (TNP) as the sole precursor of GQDs. During the hydrothermal process, TNP molecules undergo an intramolecular fusion to form GQDs, which simultaneously decorate on the surface of TiO₂ nanoparticles, leading to a strong surface interaction between the two components. The effective coupling of GQDs on TiO₂ can effectively extend the light absorption of the TiO₂ to visible region and enhance the charge separation efficiency of TiO₂/GQDs composites as a result of GQDs acting as a photosensitizer and an excellent electron acceptor. These key advances make the TiO₂/GQDs photocatalyst highly active towards the H₂ evolution reaction, resulting in 7 and 3 times higher H₂ evolution rate and photocurrent response at optimal GQDs content than TiO₂ alone, respectively. This study provides a new methodology for the development of high-performance GQDs modified semiconductor photocatalysts for energy conversion applications.