Easily prepared high-quantum-yield CdS quantum dots in water using hyperbranched polyethylenimine as modifier

The quantum yield of prepared CdS quantum dots is enhanced through PEI modification from 30 up to 95%. It is an impressive effect. The prevalent strategy of growing a shell on top of nanocrystal core for enhancement of quantum yield has a highest reported enhancement of 85%. Which method is better needs to be reconsidered.