Electroluminescence of cadmium selenium nanocrystals synthesized in aqueous solution

Cadmium selenium (CdSe) nanocrystals in aqueous system upon addition of mercaptoacetic acid as a stabilizer were synthesized. These were observed in a transmission electron microscope (TEM) and photoluminescence (PL) in aqueous solution were further measured to confirm its nanometer scale size. A surfactant was used to transfer the nanocrystals from the aqueous solution to organic solvent so that both CdSe and poly(N-vinylcarbazole) (PVK) were able to mix sufficiently in organic solvent. A multi-layer structured electroluminescence device was fabricated using a CdSe:PVK thin film as the emitting layer. PL and electroluminescence (EL) properties of the CdSe:PVK film were studied. It was found that CdSe dominated the emission in EL spectra and PVK served primarily as a hole injection and transport media.