Abstract
A range of sputteredmetalcarbideinterference filters has been prepared on copper substrates. These show promise as high‐temperature‐stable selective surfaces for solar energyphotothermal conversion. Solar absorptances of 75%–80% and room temperature emittances of about 2% can be obtained at 300 K for single layer metalcarbidefilms on bulk copper. The emittance of an ironcarbidefilm on copper increased to 7% at 600°C. The solar absorptance of the same film was temperature independent up to 500°C. Absorptances of 80%–90% and room temperature emittances of about 4% can be obtained for two‐layer interference filters on copper. The coating of both glass and metal surfaces is discussed.