Room-Temperature Synthesis of Carbon Dot/TiO2 Composites with High Photocatalytic Activity

Benefitingfrom the wide-range absorption and adjustableenergygap, carbon dots (C-dots) have attracted a great deal of attentionand they have been used to sensitize semiconductor nanocompositesto boost the efficiency of energy conversion devices, while thereis still a lack of fundamental understanding of the interaction betweensuch materials and their influence on the catalytic activity on thereaction process. In this study, C-dots were used to modify TiO2 to form a direct Z-scheme (DZS) junction for enhancementof the photocatalytic activity. The C-dot/TiO2 compositewas prepared by ultrasonication at room temperature through couplingbetween the Ti-O-C bond and electrostatic interaction.The C-dots can dramatically enhance the absorption of the compositeby forming the DZS, and the composite is enabled to generate morefree radicals, which facilitate similar to 10 times higher photocatalyticactivity compared to that of TiO2. As a proof of concept,the as-prepared C-dot/TiO2 was used for textile wastewaterdye degradation. This study provides an efficient approach for room-temperaturepreparation of C-dot/TiO2 composites with high photocatalyticactivity.

Automated summary

In this study, carbon dots were used to modify TiO2 to form a direct Z-scheme (DZS) structure, enhancing the photocatalytic activity. The C-dot/TiO2 composite was prepared by ultrasonication at room temperature through the Ti-O-C bond and electrostatic interaction. The composite showed significantly improved absorption and generated more free radicals, leading to approximately 10 times higher photocatalytic activity compared to TiO2. This study provides an efficient approach for preparing C-dot/TiO2 composites with high photocatalytic activity at room temperature.