The Size Effect of Semiconductor Quantum Dots (QDs) as Photocatalysts on PET-RAFT Polymerization
The use of semiconductor quantum dots (QDs) as a means of photocatalysts for photo-induced electron or energy transfer (PET) RAFT polymerization is increasingly attractive owing to the stable photo activity and efficient charge transfer. However, previous studies were lack in the field of the quantum size effect of QDs particles which is known to have great effect on the light absorption and charge transfer. Therefore, the aim of this work is to investigate the PET-RAFT polymerization with different size of CdSe QDs. With the increase of QDs particle size, the polymerization rate remarkably increased (higher apparent propagation rate constant kpapp) and the experimental molecular mass fit better with the theoretical values (I* = Mn,th/Mn,GPC, close to 1), indicating more ideal control radical polymerization system with larger QDs. Furthermore, the better controllability with larger CdSe QDs can be extended to PET-RAFT system with different irradiation light, solvent and monomers. This work is considered to be an essential part of the semiconductor QDs catalyst PET-RAFT polymerization and will be a reference for the further study.