Optical and structural analysis of sol-gel derived Cu-Co-Mn-Si oxides for black selective solar nanocomposite multilayered coatings

In this paper, we report the preparation of the precursor solutions for the deposition of Cu-Co-Mn-Si oxides by a sol-gel method in order to produce black selective coatings for CSP receiver tubes. Their optical properties were investigated by means of spectroscopic ellipsometry. High Resolution Transmission Electron Microscopy (HRTEM) was used to visualize the microstructure. Time-of-Flight-Secondary-Ion-Mass-Spectroscopy (ToF-SIMS) and X-ray Photoelectron Spectroscopy (XPS) were employed to determine the profile of atomic distribution and their chemical environment in a triple layered coating on a stainless steel (SS) substrate. The studied material shows high potential for the use in multi-layered graded index coatings for solar energy conversion.