Band Gap Engineering of CdTe Nanocrystals through Chemical Surface Modification

摘要

The size-dependent optical properties of semiconductor nano-crystals have recently motivated attempts to use them as novel building blocks for optoelectronics and bioengineering applications.To attain these ends,the ability to prepare semiconductor nano-crystals with controlled size and composition is of primary importance.A variety of methods are now accessible for preparing size-controlled II-VI semiconductor nanocrystals such as CdS,CdSe,and CdTe nanocrystals.With the exception of size-selective photoetching of CdS nanocrystals,control of the nanocrystal band gap has mostly been achieved via "growth" of nanocrystals during synthesis.Other approaches have modified the optical properties of the nanocrystals by creating inorganic shells or alloying or by compensating surface defects with organic molecules.