An energy-efficient and low-driving-voltage flexible smart window enhanced by POSS and CsxWO3

Smart windows with controllable visible and near-infrared (NIR) light transmittance are highly desirable for energy-saving buildings. Herein, we propose a hybrid polymer dispersed liquid crystal (PDLC) film for smart window applications, which combines dopants of polyhedral oligomeric silsesquioxane (POSS) and cesium tungsten bronze (CsxWO3). The low surface free energy of POSS and NIR absorption of CsxWO3 endow the film with enhanced electro-optical performance (ultra-low driving voltages, high contrast ratio and low optical haze value) and maneuverable light modulation in visible and NIR range. A model house equipped with the proposed film as smart windows reveals its outstanding light shielding and temperature regulating abilities that the indoor temperature rises less than 5oC after irradiation for 10min under the experimental conditions. The research provides new opportunities for further development of energy-efficient smart windows, especially for cooling energy saving in buildings. •A hybrid PDLC film is proposed that can modulate the light passage in both visible and near-infrared ranges.•CsxWO3 is introduced to absorb the near-infrared radiation.•Both CsxWO3 and POSS can enhance the electro-optical properties of PDLC.•The as-fabricated film can regulate indoor temperature if used as smart windows.