Effect thickness of copper oxide thin films on structural, optical, electrical, and hydrophobic properties for use in self-cleaning technique

Abstract

In this work, copper oxide thin films were deposited by pneumatic spray pyrolysis method on a microscopy glass substrate, heated at 400°C for different deposition times (5min, 10min, 15min, 20min,25min, and 30min) using a 0.1M of precursor concentration. These films are characterized by X-ray diffraction (XRD), Fourier-transform infrared (FT-IR), spectroscopic ellipsometry, UV-visible spectroscopy, four points method, and water contact angle. According to the XRD, all peaks confirm the formation of the phase tenorite of the monoclinic structure. The deposited were polycrystalline copper oxide CuO with directions along (111) plane, the crystallites size between 14 and 23 nm. FTIR spectroscopy confirms the presence of the CuO phase and agrees that it will result in XRD. From the transmission spectra, the average transmission between 400 and 800nm is 65% to 50%, and the gap energy is 2.65 eV to 1.09 eV. The water contact angle values in all samples are greater than 90° and range from 96.4° to 103.2°, as we can see from these results that all the samples are hydrophobic films.