Temperature-dependent infrared optical and radiative properties of platinum

Far-field radiative thermal rectification with bulk materials

“…This marked difference in its emissivity behaviours at higher temperatures enables Ni in combination with other materials to yield RTR of 60%. The other metals like Pt [102], Cu [87] and the refractory metal W [104] exhibit negligible variation of their emissivity as a function of temperature, though showing the same as any metallic emissivity behaviour, elucidating the reason behind such low RTR(%)<5% with most material combinations. This is however not the case for Au [104], where the temperature rise decreases the already low emissivity of the material significantly, making it highly reflective.…”