Thermal stability investigation of the SS/MO/Al2O3 spectrally selective solar absorber coatings. (3rd July 2019)

• Record Type: Journal Article
• Authors: Lu, Jia-Zheng; Chen, Bao-Hui; Jin, Ling-Hua; Fang, Zhen; Liu, Gang; Gao, Xiang-Hu
• Is Part Of: Surface engineering. Volume 35:Number 7(2019)
• Page Start: 565
• Page End: 572
• Publication Date: 2019-07-03
• Subjects: Spectrally selective coating -- thermal stability -- microstructure -- annealing; Surfaces (Technology) -- Periodicals; Coatings -- Periodicals; 620.4405
• DOI: 10.1080/02670844.2018.1537083
• Languages: English
• ISSNs: 0267-0844

Abstract

ABSTRACT: A novel Mo/Al2 O3 spectrally selective solar absorber coating is deposited onto stainless steel (SS) substrates using magnetron sputtering method, which exhibits a high absorptance ( α ) of 0.90 and a low emittance ( ε ) of 0.08. In order to investigate the thermal stability, the SS/Mo/Al2 O3 coatings are annealed in air and vacuum at different temperatures. The surface morphology, microstructure, composition distribution, diffusion and optical properties before and after high-temperature annealing are characterised by scanning electronic microscopy (SEM), atom force microscopy (AFM), X-ray diffraction (XRD), micro-Raman spectroscopy, UV–vis spectrophotometer and emissometer. Experimental results indicate that the coatings are stable in air at 350°C. The values of solar absorptance and emittance below 350°C are 0.87–0.90 and 0.06–0.08, respectively. The coatings remain stable after annealed at 600°C in vacuum for 2 h with a good spectral selectivity ( α / ε ) of 0.89/0.06.