Highly Transparent, Deformable, and Multifunctional AgPdCu/ITO/PTFE Hybrid Films for Self-Cleaning, Flexible, and Energy-Saving Smart Windows

Rollable, bendable, twistable, and foldable polymer–oxide–metal multistacked hybrid films are demonstrated, which simultaneously act as multifunctional electrodes in flexible polymer-dispersed liquid crystal (PDLC) windows and flexible and transparent thin-film heaters (TFHs) for self-cleanable and flexible smart windows. By continuous sputtering of a thin polytetrafluoroethylene (PTFE)–indium tin oxide (ITO)–AgPdCu (APC) multilayer on a colorless polyimide substrate, transparent and multifunctional films are fabricated with a low sheet resistance of 7 Ω □⁻¹, high optical transmittance of 83% at a wavelength of 550 nm, low transmittance in the infrared region, and a high contact angle of 109°. Based on inner/outer bending, rolling, twisting, and folding tests, the outstanding flexibility of these PTFE/ITO/APC multistacked films is demonstrated. The flexible PDLC and flexible TFHs with PTFE/ITO/APC multistacked electrodes show a controllable transmittance range between the on and off states that is nearly 40%, and a high saturation temperature of 111 °C is observed at a low applied voltage of 4 V. The multifunctional properties of the flexible PDLC and TFHs fabricated on PTFE/ITO/APC hybrid films indicate that the polymer–oxide–metal hybrid film is a versatile transparent electrode that can be used for flexible, smart, and energy-saving windows.