| Autor: |
Abdallah Merrouche, Amor Azizi, N. Fenineche, Abdellah Henni, Laid Telli, S. Walter |
| Rok vydání: |
2015 |
| Předmět: |
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| Zdroj: |
Materials Science in Semiconductor Processing. 40:585-590 |
| ISSN: |
1369-8001 |
| DOI: |
10.1016/j.mssp.2015.07.046 |
| Popis: |
In this work, ZnO nanostructures are electrodeposited on a transparent conducting glass from chloride baths. The influence of H 2 O 2 concentration on the electrochemical characteristics has been studied using cyclic voltammetry (CV) and chronoamperometry (CA) techniques. From the analysis of the current transients on the basis of the Scharifker–Hills model, it is found that nucleation mechanism is progressive with a typical three-dimensional (3D) nucleation and growth process; independently with the concentration of H 2 O 2 . However, the nucleation rate of the ZnO changes with the increase of H 2 O 2 concentration. The Mott–Schottky measurements demonstrate an n-type semiconductor character for all samples with a carrier density varying between 5.14×10 18 cm −3 and 1.47×10 18 cm −3 . Scanning electron microscopy (SEM) observations show arrays of vertically aligned ZnO nanorods (NRs) with good homogeneity. The X-ray diffraction (XRD) patterns show that the ZnO deposited crystallises according to a hexagonal Wurtzite-type structure and with the c -axis perpendicular to the electrode surface. The directional growth along (002) crystallographic plane is very important for deposits obtained at 5 and 7 mM of H 2 O 2 . The high optical properties of the ZnO NRs with a low density of deep defects was checked by UV–vis transmittance analyses, the band gap energy of films varies between 3.23 and 3.31 eV with transparency around 80–90%. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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