Thermochromic materials are of high interest for their potential applications in spacecraft thermal control, with systems exhibiting variable emissivity able to manage the heat rejection and absorption. VO2 presents one of the most prominent technological options for thermochromic behaviors, with a transition temperature around 68°C limiting its practical utility for spacecraft thermal control notably. Here, we report the synthesis of strongly thermochromic tungsten doped vanadium dioxide coatings on silicon wafers obtained in an industrial-size vacuum deposition chamber. Samples with various W doping rates were deposited by magnetron sputtering, exhibiting thermochromic transition temperatures from 38°C to as low as 5°C, with optical transmission contrasts at a wavelength of 12 µm maintained between 40% and 58%, enabling enhanced control of heat exchange at low temperature and broader usability. The variable emissivity radiators were measured to have emissivity contrasts up to 40%, with transition temperatures as low as 10°C, demonstrating the potential use of the VO2-based thermochromic coating.
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