Effect of dye extracts on the optical properties of chemically deposited ZnS thin films
Journal Title: Journal of New technology and Materials - Year 2017, Vol 7, Issue 2
Abstract
The study reports on the influence of dye extracts of Naulcea latifolia (Uvuru-ilu) leaves on the optical properties of Zinc Sulphide (ZnS) thin films grown by the chemical bath deposition method. The concentration of the ZnS thin films were varied in the range 0.1 M to 0.7 M and other deposition variables (pH, and bath temperature) were kept constant. The films were characterised using optical spectroscopy (transmittance versus wavelength, reflectance versus wavelength, absorbance versus wavelength) to investigate the optical constants (optical absorption coefficient, energy bandgap, extinction coefficient and the optical density). The results show that the transmittances of the dye –sensitized films were higher compared to the as-deposited layers. The transmittance exhibited a concentration dependent behaviour for films grown without addition of the dye extracts. The transmittance were typically < 50 % for the non dye-sensitized ZnS thin films grown at concentrations ≤ 0.3 M and > 50 % for films grown at concentrations ≥ 0.5 M. However the presence of the dye extracts increased the transmittances significantly, independent of the different concentrations used. The energy bandgap was direct, with values ≤ 3.60 eV for films grown at concentrations ≥ 0.5 M and 3.80 eV for films grown at lower concentrations. These values strongly suggest the use of these films in optoelectronic applications and related device designs.
Authors and Affiliations
P. A. Nwofe
Self organizing map of artificial neural network for groundwater quality classification in the F'kirina plain (Oum El Bouaghi province-NE of Algeria)
The topological Self-Organizing Maps of Kohonen and other methods of artificial intelligence are effective tools for modeling and solving environmental problems. In this study, we propose an approach to classify the annu...
Effect of Al doping on the structural and optical properties of SnO2 thin films elaborated by sol-gel technique
In this study, the influence of increasing of the Al concentration on the structural and optical properties of SnO2 thin films were investigated. Pure and aluminum-doped SnO2 thin films were prepared by sol–gel depositio...
The effect of sliding speed and normal load on the friction and wear behavior of TiO2 thin films
The tribological behavior of TiO2 thin films was investigated against test parameters. The friction coefficient under different normal loads, sliding speeds, and numbers of cycles was studied using a micro-scratch tester...
The heterostructure ZnO/Al/SiO2/Si fabrication for Piezoelectric SAW and BAW Transducers and Sensors
Zinc oxide (ZnO) thin films were deposited by pulsed laser deposition technique for making ZnO/Al/SiO2/Si Bulk and Surface Acoustic Wave (BAW and SAW) transducers. The aim is to improve the piezoelectric properties of th...
Preparation and characterization of CIS thin films obtained by electrodeposition onto ITO and Mo substrates
In this study, thin films of copper and indium selenide (CuInSe2) were electrochemically deposited on ITO glass substrates and Mo films. A three electrodes system is used for in-situ monitoring of the deposition process...