Optimization of Synthetic Conditions for the Preparation of Core–Shell Structures of CdTe/ZnSe QDs in Water

Abstract

Quantum dots (QDs) are nanocrystal semiconductors that feature unique optical properties. However, they have a high density of dangling bonds on their surface, causing defects that can compromise their fluorescence. Their superficial passivation using another semiconductor is an alternative to reduce these defects. Herein, CdTe QDs stabilized with mercaptusuccinic acid (MSA) and cysteamine (CYA) were synthesized in water and coated with a ZnSe layer, forming a core–shell heterostructure. An improvement in photoluminescence greater than 300% was obtained for CdTe/ZnSe-MSA. However, for CdTe/ZnSe-CYA, the emission enhancement was around 55%. This study reinforces the importance of the experimental conditions to optimize QDs’ emission.

Keywords

• semiconductors
• fluorescence
• mercaptosuccinic acid
• cysteamine