Al-dopedZnONanostructured Thin Films: Density Functional Theory and Experiment

Abstract

Nanostructured Al-doped ZnO (AZO)¯lms are deposited on glass substrates by electroless deposition technique in the present work. AZO¯lms with Al concentration from 1 at.% to 5 at.% are investigated for their structural and morphological properties by X-ray di®raction (XRD), and atomic force microscopy (AFM). An excellent homogeneity is achieved with average crystallite sizes of below 32 nm and a nearly constant root mean square (RMS) surface roughness between 1 nm and 3 nm, for various Al doping concentrations. These smooth and uniform lms are characterized for their optical and photoluminescence (PL) properties. A higher value of average transparency between 79% and 92% in the wavelength range of 300-800 nm is achieved, and the PL intensity is found to be a strong function of doping. Density functional theory (DFT) calculations agree with the measured transmittance values, in addition to their Int. J. Nanosci. 2015.14. Downloaded from www.worldscientific.com by NANYANG TECHNOLOGICAL UNIVERSITY on 08/23/15. For personal use only.predicted electronic structure. Moreover, time-resolved PL measurements indicate that the luminescence decay time decreases with increased doping concentration.

Experimental and ab initio study of the structural and optical properties of ZnO coatings: Performance of the DFT+U approach

“…Based on its good performance in the pure compound, the DFT+U approach has also been proposed to model the case of ZnO doped with transition metals and lanthanide atoms [28,29,[31][32][33][34][35][36]. So, nowadays, investigations that combine experimental determinations and DFT+U predictions are quite common, because this combination allows a deeper understanding of the materials through the relation of the observed properties and the modelling of their origins [34,[36][37][38][39][40].…”