Temperature Dependent Photoluminescence of CuInS2 with ZnS Capping
Abstract
The commercial interest in Cd-free quantum dots for photonic and biomedical applications, has significantly increased in the last ten years. Due to high quantum yield, good spectral distribution, and weak photobleaching, semiconductor nanocrystals (SNCs) of Copper Indium Disulfide (CIS) have been considered for such applications. For CIS SNCs, the optical properties are characteristic of quantum-confined excitons within the nanocrystal boundary, while a notable blue shift from bulk materials is observed. CIS SNCs are highly sensitive to compositions, morphologies, and lattice strains allowing them to display unique optical and electronic properties. Temperature- dependent photoluminescence (PL) studies of CIS and CIS capped with Zinc Sulfide (ZnS) SNCs were carried out in temperatures ranging from 6K 300K. In this work, PL quenching is observed for various optical transitions that occur in the SNCs which correspond to specific energy transitions within the nanocrystals. Temperature-dependent spectroscopy revealed the interface- defect and surface-defect transitions were thermally active at low temperatures; however for CIS/ZnS the intrinsic-defect states were relatively stable because the strong Coulomb interaction between charge carriers.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 11, 2014
- Accession Number
- ADA625443
Entities
People
- Quinn A. Hailes Jr.
Organizations
- Hampton University