Numerical Study of Alloy/Nanocomposite-based Solar Selective Absorber with High Photo-Thermal Conversion Efficiency

Based on the four-layered metal/dielectric film structure with high optical absorption in the 400-1000 nm spectral range, a new four-layered film structure has been studied and designed to improve the optical absorption with the spectral range being expanded to 250-1600 nm. After analyzing the advantages and disadvantages of the different metals and dielectric materials, the most suitable materials for this film structure have been chosen. In terms of Bruggeman model, the optimized optical constant of alloys has been carefully analyzed to achieve the best solar absorption performance of the SSA device. Afterwards, Maxwell Garnett model was used to fit the optical constants of the metal-dielectric material, which satisfies the conditions and properties of the SSA device required in applications.