Preparation and overall energy performance assessment of wide waveband two-component transparent NIR shielding coatings

Solar heat blocking materials, which can not only strongly shield the near infrared (NIR) heat rays, but also retain high visible transparency, have been widely studied and used in energy conservation of buildings. In this work, a complete process for preparation of waveband two-component transparent NIR shielding (WTNS) coatings combined ATO (antimony doped tin oxide) and Cs0.33WO3 nanomaterials is proposed. ATO and Cs0.33WO3 were synthesized by controllable hydrothermal methods and dispersed by a ball mill with silane coupling agents. The transmittance spectra demonstrate that WTNS coated glass shows excellent NIR shielding performance in a wide-band wavelength from 780 nm to 2500 nm, which could shield the NIR light as much as 90.9% and retain high transparency in the visible light of 70.6%. The overall energy performance assessment of this NIR shielding coatings was obtained, which includes thermal chamber test and software simulation in EnergyPlus. The chamber tests reveal the superior thermal insulation ability of WTNS coatings. The simulations indicate that for the area like Hong Kong which is cooling dominated areas, WTNS coated glass has the best energy performance which can significantly save up to 15.22% and 9.15% electricity per year in comparison with the normal glass and low-e glass, respectively.