Optical modeling of multilayered coatings based on SiC(N)H materials for their potential use as high-temperature solar selective absorbers

• Published in: Solar energy materials and solar cells 2013-10, Vol.117, p.315-323
• Main Authors: Soum-Glaude, Audrey, Bousquet, Isabelle, Thomas, Laurent, Flamant, Gilles
• Format: Article
• Language: English
• Subjects: Absorptance; Absorptivity; Applied sciences; Chemical vapor deposition; Coatings; Concentrated solar power; Electrical engineering. Electrical power engineering; Emittance; Energy; Exact sciences and technology; High temperature solar selective coatings; Materials; Materials selection; Natural energy; Optical modeling and characterization; Plasma enhanced chemical vapor deposition; SiC thin films; Simulation; Solar collectors; Solar energy; Solar thermal conversion; Stacks
• ISSN: 0927-0248; 1879-3398
• DOI: 10.1016/j.solmat.2013.06.030

SiCH thin films grown from Ar/tetramethylsilane plasmas (PECVD) were evaluated as absorber layers in selective coatings for high-temperature solar receivers. SiCH coatings are used in thermomechanical applications because of their good thermal stability. A SiCH film with an absorption index k(430nm)=0.11 was taken as a reference for optical simulations of refractory metal–SiCH multilayer stacks and cermets. The transfer matrix method and Maxwell–Garnett effective medium approximation were used to calculate the spectral reflectance and transmittance of the selective absorbers. Their solar absorptance and thermal emittance were also deduced. A seven-layer stack with alternating metal and SiCH layers was found to present a simulated solar absorptance of 0.92 and thermal emittance of 0.08 at 500°C. •High temperature solar selective absorbers based on SiCH coatings were evaluated.•The optical response of metal–SiCH cermets and multilayer stacks was simulated.•A seven-layer structure with αS=0.92 and ε(500°C)=0.08 was identified.•Solar power plant efficiency with coated receivers was also estimated.•The simulated coatings are suitable for high temperature CSP selective absorbers.