Cr/α-Cr2O3 Monodispersed Meso-spherical Particles for Mid-temperature Solar Absorber Application

Monodispersed meso-spherical particles of Cr/α-Cr2O3 cermet Aqueous Chemical Growth (ACG) coatings investigated within this contribution could be successfully employed in mid temperature solar absorber applications. Their selectivity depends on their chemical, physical and structural characteristics and related optical properties like reflectance, emittance, solar light absorption, or absorptance and transmittance. Parameters such as deposition temperature, pH of the initial precursor and substrate roughening will greatly influence their relevant optical properties as reported. The coated Cr/α-Cr2O3 spherical particles on rough Molybdenum and Tantalum substrates by a simple, green and cost-effective method were characterized by scanning electron microscopy, energy dispersive spectrometry, Raman spectroscopy, and diffuse reflectance UV-VIS-NIR spectroscopy. The samples deposited on Tantalum substrate exhibit the targeted high absorbing optical characteristic “Black chrome” while those deposited on molybdenum substrate show a significant high diffuse reflectance.