Search

Abstract: A new solar selective absorbing coating of NbTiON/SiON was prepared on Cu substrate using a reactive magnetron sputtering method. The new coating exhibits a high absorptance (α) of 0.95 and a low emittance (ε) of 0.07, and the thickness of NbTiON and SiON layers was optimized to achieve high solar selectivity. The spectral properties (α/ε) of the coating on Cu substrate are stable (0.94/0.08) even after heat-treatment at 500°C in vacuum for 40h, but decreased at 600°C. If the substrate is replaced by stainless steel (SS), the coating exhibits better stability, which indicates its potential applications in intermediate temperate solar absorber. [Copyright &y& Elsevier]

Abstract: Mo–Al2O3 solar selective absorbing coating was deposited on stainless steel substrate by magnetron sputtering. The evaluation of high temperature stability indicates that the degradation of the optical properties is due to the diffusion and oxidation of single metal Mo in the ceramic Al2O3. Mo diffuses easily in Al2O3 layer and the interface between the double Mo–Al2O3 layers when aging temperature is above 400°C, which was observed by SEM and AES with etching depth. The thermal stability was improved significantly when a denser Mo–Al2O3 layer was obtained by optimizing the deposition parameters. [Copyright &y& Elsevier]