Structural and spectroscopic ellipsometry characterization for electrodeposited ZnO growth at different hydrogen peroxide concentration

Optical Band Gap Estimation of ZnO Nanorods

“…Photo activated applications such as solar cells, H 2 generators and photocatalysis, generally require the knowledge of the refractive index, absorption coefficient, band bap (BG) or any other optical parameters that serve to predict the performance of the employed materials [1][2][3][4][5] . The term BG is usually determined when the photo stimulated generation of electrons and holes at a certain wavelength is required, leading to a more accurate employment of the light sources and materials according to the selected application.…”

“…In practice, the estimation of the BG becomes feasible within the use of indirect methods, commonly by the Tauc's plot, which demands the computation of the absorption coefficient (α). Then, α can be determined from the fitting or processing of ellipsometric or spectroscopic measurements 1,2 . According to literature, the employment of the ellipsometric technique is often recommended as it can lead to the determination of more reliable optical properties.…”

“…However, it is still an indirect methodology that requests fitting models for the analysis of the data. Nevertheless, the available models are not suitable for all nanostructures, particularly when a rough surface has been developed 1,2 . In fact, this is why the utilization of the spectrophotometric technique combined with standard optical equations that require the measurement of only Transmittance and Reflectance is commonly accepted [6][7][8][9][10] .…”

Temperature annealing effect on structural and optical properties of ZnO thin films prepared by sol-gel method

“…It is also shown that sol-gel is an adapted technique to obtain ZnO films with a quality comparable with that of transparent conducting oxide thin films prepared by other techniques [10,11].…”

“…These characteristics are required in various applications dealing with transparent heating elements for photovoltaic devices, transparent electrodes used on electroluminescence devices and gas sensors [4][5][6][7]. Many papers report on the physical properties of ZnO obtained by various deposition techniques such as reactive RF and DC sputtering [8], chemical vapor deposition [9], spray pyrolysis [10], electrode position [11] and sol-gel technique [12]. Particularly,the attractive deposition technique among these mentioned is the solgel one for being successfully used for transparent semiconducting film.…”