Mid-infrared optimized electroreflective device based on PEDOT/PSS

A new type of device with adjustable reflective capabilities in the mid-IR is elaborated from the combination of Poly (3,4-ethylenedioxythiophene)/Poly (styrenesulfonate) (PEDOT/PSS), gold-coated non-porous polyimide substrate and gel electrolyte. Prior to device characterization, the influence of polymer thickness and gold substrate types on reflectance modulation of PEDOT-Au films is scrutinized to obtain the film with optimum quality. A combination of SEM images and reflectance curves confirms that adopting thin PEDOT/PSS on the non-porous substrate can achieve large amplitude reflectance regulation. Further, a mechanical perforating method is developed to address the issue that ions cannot transport between the polymer film and the counter electrode when this PEDOT/non-porous film assembled into device. An in-depth study shows that by varying the punching side, porosity and aperture, a device with front holes of porosity 12.77% affords the highest reflectance contrast of 0.566 over the wavelength range of 3-5 μm, meanwhile exhibits effective temperature changes of approximately 16 °C. These results inspire interesting perspectives regarding the fabrication of PEDOT-based devices with controllable IR electroreflective performance.