Abstract
Solar control characteristics of chemically deposited PbS and CuxS thin films in the glass-PbS-CuxS structure are reported. This combination offers pleasing colours: bluish, greenish, greenish-yellow etc in reflected daylight and low NIR transmittance-not possible with PbS-only coatings, while providing a high-enough NIR solar reflectance-not achievable with CuxS-only coatings. A 15 min air bake at 150 degrees C has been found to reduce the sheet resistance of the CuxS films by two to three orders of magnitude, which in turn drastically decreases the integrated NIR transmittance, T*(IR), of the PbS-CuxS combination (typically from 46% to 14%), while retaining the integrated transmittance, T*(vis), and the integrated reflectance, R*(vis), in the visible region to within 14-30% and 15-20% respectively for the various PbS-CuxS combinations. The major advantage of the PbS-CuxS thin film combinations as solar control coatings is that by controlling the thicknesses of the individual films a range of combinations of T*(vis), R*(vis), T*(IR), R*(IR) and colour in reflected daylight is achievable. This makes them very versatile for architectural glazing applications to suit different space conditioning, illumination level and cosmetic requirements.
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