Preparation of CdSe nanocrystals in organic system and electroluminescence characteristics of the devices

Abstract:

CdSe nanocrystals were prepared by a colloidal chemical approach using CdO and Se powder as precursors in an organic system of TOPO/TOP, and a multilayered electroluminescence device was fabricated with CdSe as emitting layer. The results show that the photoluminescence spectra of the CdSe nanocrystals almost cover the whole visible region and the full width at half maximum (FWHM) is appropriately 200 nm. The electroluminescence spectrum of the multilayered device at different voltages was investigated. The electroluminescence intensity is enhanced with increasing operating voltage, and the CIE coordinates of the device change from (0.34, 0.37) at 6 V to (0.44, 0.46) at 20 V as the operating voltage increases, which indicates that the colors of the device could be tuned by the operating voltage. Supported by the National Natural Science Foundation of China (No. 90301004, No. 10434030 and No. 60406005); the “973” National Key Basic Research Special Foundation of China (No. 2003CB314707); the New Star Program for Science and Technology of Beijing City (No. 2004B10).