Structure, microstructure and determination of optical constants from transmittance data of co-doped Zn0.90Co0.05M0.05O (M Al, Cu, Cd, Na) films

Abstract

ZnO, Zn 0.95 Co 0.05 O and Zn 0.90 Co 0.05 M 0.05 O (M@Al, Cd, Na, Cu) single phase films have been successfully synthesized by ultrasonic spray pyrolysis technique. Structural analysis by X-ray diffraction show that all the films have hexagonal wurtzite structure with an average crystallite size in the range of 19-25 nm. SEM analysis revealed that Cd and Na preserve the shape of nanopetals observed with ZnO or CoAZnO films, while the doping with Al or Cu promote the formation of dense films constituted of nanorods. By the application of Levenberg-Marquardt least square method, the experimental transmittance data were fitted perfectly with the transmittance data calculated via a combination of Wemple-DiDomenico model, absorption coefficient of an electronic transition and Tauc-Urbach model. The concentration of absorbing centres N Co and oscillator strength f of d-d transition of Co 2+ ions are calculated from Smakula's formula.

A holistic analysis of surface, chemical bonding states and mechanical properties of sol-gel synthesized CoZn-oxide coatings complemented by finite element modeling

“…The experimental transmittance data perfectly fits with the theoretical calculations. The Levenberg-Marquardt least square method in combination with the Wemple-DiDomenico model were utilized to understand the electronic transition, optical absorption coefficient, and Tauc-Urbach theory [39].…”

Cadmium effect on optical properties of Cu2Zn1−xCdxSnS4 quinternary alloys nanostructures

“…Additionally, the width of the band tail of the localized states (E t ) inside the energy gap was calculated using the Urbach formula (Stoica et al, 2006;Roguai et al, 2014) x=0…”

Properties of Undoped and (Al, In) Doped ZnO Thin Films Prepared by Ultrasonic Spray Pyrolysis for Solar Cell Applications

“…ZnO can be doped with a wide variety of ions. The ZnO doping is achieved by replacing Zn 2+ atoms of elements of higher valance such as In 3+ , Al 3+ , Sn 4+ and Pb 4+ [16]. The structural, morphological, optical and electrical charac-terization of undoped and doped ZnO films were evaluated.…”