Design and Fabrication of Highly Environmental Stable Cr-Fe-Ni Oxides/ ZrO2-SiO2 Composite Oxide Based Tandem Absorber for Solar Thermal Power Generation Applications
Abstract
A new Cr-Fe-Ni oxides/ZrO2-SiO2 composite oxide based tandem absorber is designed and developed for high performance ORC based solar thermal applications. The Cr-Fe-Ni composite oxide based absorber layer is designed to have nanoporous structure and covered with an antireflective protective layer. The tandem absorber layer was developed by a combination of chemical and sol-gel methods. By varying process parameters like duration, temperature and withdrawal speed, different combinations of Cr-Fe-Ni oxides/ ZrO2-SiO2 composite absorber layers with varying refractive indices were developed on a suitable SS substrate. The optimized thickness of absorber layer along with the antireflective layer exhibited high absorptance (α= > 0.94) and low thermal emittance (ε = 0.11– 0.14 at 300 °C). More specifically, this novel tandem coating has excellent optical properties along with high corrosion resistance (withstands > 400 h in salt spray test). It has good thermal stability in an open air atmosphere and is well suited for low and medium temperature solar thermal applications.
Keywords
Tandem absorber layer, Cr-fe-ni composite oxide, Zro2-sio2, Antireflective layer