Shape Control of CdTe Nanocrystals Based on Crystalline Phase and Reaction Parameters

Abstract

The size- and shape-control of nanocrystals have a significant impact on the physical and chemical properties of the semiconductor nanocrystals. Among various semiconductor nanocrystals, CdTe nanocrystals have drawn keen attention due to its simplicity in chemical composition with wide optical bandgap (~1.45 eV) and high absorption coefficient (10-4 cm-1), abundance of raw materials, and excellent stability. Herein we demonstrate the several mechanisms to control the size and shape of CdTe nanocrystals based on the continuous precursor injection (CPI) approach which has excellent controllability and processability. By manipulating surface energy of the CdTe nanocrystals, injection rate and reaction temperature, we controlled size and shape of CdTe nanocrystals from dot to hyperbranched tetrapod. These shape- and size-controlled CdTe nanocrystals present promising potential for building blocks in various optoelectronic applications.