Structural and Optical Characterization of Electrodeposited Black Chrome-Graphite Encapsulated FeCo Nanoparticles Composite Solar Selective Coatings

Abstract

      Black Chrome-graphite encapsulated FeCo nanoparticles (BC-GE FeCo NPs) composite based solar selective coatings were prepared on substrates such as stainless–steel, Cu and Ni-coated Cu employing electrodeposition technique. Electrodeposition was done by addition of three different weight proportions of GE FeCo NPs (0.025, 0.05, and 0.1) in the electrolyte bath. X-ray diffraction, Atomic Force Microscopy, UV-Visible and FTIR spectroscopy were used to characterize the structural and optical properties of these coatings. The major content of the deposited film is contributed by Cr (ICDD 74-7045), Fe-Cr (ICDD 34-0396), Fe₂AlCr (ICDD 54-0387) and FeCr_0.29Ni_0.16C_0.06 (ICDD 33-0397) as deduced from XRD. Spectral reflectance of the selective surface is observed to be low in UV-Visible region even after the addition of GE FeCo NPs. The low surface reflectance in the near infrared region due to the addition of GE FeCo NPs indicates increase in the absorptance of the selective surface in near infrared region. Atomic Force Microscopy indicated that film smoothness increases and grain size decreases with decrease in the weight percentage of GE FeCo NPs. Hardness and Young’s modulus were found to decrease with decreasing weight percentage of GE FeCo NPs.

Keywords: Electrodeposition; Black Chrome; Graphite encapsulated FeCo NPs, solar selective coatings