In-situ and post annealing effect on the microstructure and the optical properties of black Cu-Co-Mn oxide spinel coating for Parabolic Trough Collector (PTC) applications

The present paper deals with the deposition of Cu-Co-Mn oxides thin film by magnetron sputtering to produce a black selective coating for solar Parabolic Trough Collector (PTC) systems. The effect of temperature was studied between the nominal temperature range of 300-600°C, using both in-situ heating and post annealing. The optical behavior was investigated by advanced spectrophotometry devices in visible, near and infrared spectral ranges. Scanning Electron Microscopy (SEM) was used to show the microstructure, and X-ray Diffraction (XRD) to identify the phases and to compare the samples'pattern prepared at different temperatures.