Physical properties of electrodeposited CuO nanostructure: Potential applications as selective solar absorbers
Z.Marshet- Mihabaw1-3•, G. Gebreziabher1-2,4
1 UNESCO-UNISA Africa Chair in Nanosciences-Nanotechnology, College of Graduate Studies, Muckleneuk ridge, PO Box 392, Pretoria, South Africa
2 Nanosciences African Network (NANOAFNET), iThemba LABS-National Research Foundation, 1 Old Faure Road, Somerset West, Western Cape 7129, PO Box 722, South Africa
3 Department of PHYSICS, Debre Birhan University, Ethiopia
•Corresponding author: [email protected] Abstract
In relation to the intrinsic optical properties of Copper oxide (CuO) & its potential application as a selective solar absorber, nanostructured CuO coatings were synthesized via electrochemical deposition at room temperature on stainless steel. Following an aanealing in air at 420oC, the formation of nanostructured particles with a significant shape anisotropy.
The prepared thin films were characterized through XRD, SEM, EDS, AFM. Raman spectroscopy, UV–Vis–NIR, and cyclic voltammetry (CV). The phase observation showed the formation of base-centred monoclinic structured CuO with high crystallinity that increases its intensity with deposition time. SEM analysis showed CuO thin film with needle like structure.
Raman spectra confirmed the presence of three Cu-O vibration modes at 305, 344 and 642 cm-1. The band-gap energy of the CuO thin film derived from Kubelka-Munk (K-M) model slightly decreased from 1.34 to 1.27 eV with the increase in deposition time. The reflectance spectra from UV–Vis–NIR data reveals that the absorptance(α), of CuO thin film increases significantly with increase in depositing time while small effect on the emittance (ε). These results seem validating that the electrodeposited CuO thin films can be considered as potential candidates for selective solar absorber applications.
