Ricerc@Sapienza

This paper studies the IR properties of a VO2-based multilayer structure with an emittance that increase with the temperature. A good tunability of the emissivity in long-wave infrared spectral region (8–12 µm) has been detected, with a positive emissivity differential of about 0.2. The transition of the long wave emissivity ε with the temperature is fully reversible according to a hysteresis cycle, with a transition temperature of 67 °C and a thermal bandwidth of only 8 °C. The multilayer structure also shows two emission peaks both in the heating cycle and in the cooling cycle. This emittance performance is promising for the future development of passive thermal control systems of spacecrafts.