Rapid PL Enhancement in Cd doped Alq3 Nanowires

Abstract

Aluminium tris (8-hydroxyquinoline) (Alq3) is a popular coordination complex extensively used in organic luminescent devices as the emissive layer. Metal doping in Alq3 and its nanoscale synthesis are two strategies which are widely adopted to enhance the functional properties of Alq3. In the present work, Cadmium (Cd) doped Alq3 films having 1-dimensional morphology have been successfully synthesised using thermal vapor transport method. These films have been subjected to different analytical studies to study their functional properties. Scanning Electron Microscopy (SEM) images reveal the dendritic nature of Cd-doped Alq3 nanowires while Energy Dispersive X-ray Spectroscopy (EDAX) analysis confirms the presence of Cd in Cd-doped Alq3 nanowires. X-ray Diffraction (XRD) study reveals the polycrystalline nature of Cd-doped Alq3 nanowires. X-ray Photoelectron Spectroscopy (XPS) analysis of Cd-doped Alq3 nanowires samples indicates the replacement of some Al atoms with Cd atoms in Alq3 matrix. UV–visible spectroscopy study of the Cd-doped Alq3 nanowires shows enhancement in the optical absorbance with increasing Cd concentration while Photoluminescence (PL) spectroscopy analysis shows a 7-fold enhancement in PL intensity for 0.5 mol% Cd-doping. This rapid enhancement in the PL is explained on the basis of electronic charge transfer from Cd ions to Alq3 molecules.