Electrical and Optical Properties of Colloidal Quantum Dots and Quantum Dot Networks: Role of Surface States and Using Biomolecular Links in Network Assembly

摘要

The objectives of this paper are to determine the role of surface states in determining the electrical and optical properties of semiconductor quantum dots in colloidal suspensions, and to use biomolecules to facilitate the chemically-directed assembly of quantum dots networks with densities approximating 10~(17) cm~(-3). Absorption spectra and photoluminescence (PL) spectra of colloidal cadmium sulfide (CdS) quantum dots are analyzed to investigate the role of surface states in determining the electrical and optical properties of these semiconductor quantum dots. In addition, this work demonstrates the utility of using glycine-glycine-glycine-cysteine (GGGC) peptides and crossing-linking chemical reactions to achieve integrated networks of ZnS-coated CdSe quantum dots and CdS quantum dots.