High-performance and robust dual-function electrochromic device for dynamic thermal regulation and electromagnetic interference shielding

High-performance devices with the electromagnetic interference (EMI) shielding and dynamic thermal regulation performances are highly desirable for modern integrated electronic and telecommunication systems in areas such as aerospace, communication equipment, and smart electronics. Herein, the dual-function electrochromic (EC) device is fabricated using the polyaniline (PANI) film as the infrared (IR) EC layer, the polymethyl methacrylate (PMMA) gel polymer as the electrolyte and the MXene/PANI/poly vinylidene fluoride (PVDF)/Au (MPPA) film as the EMI shielding layer. The device exhibits a superior EMI shielding effectiveness (SE) of 36.5 dB at 11.6 GHz, benefiting from the highly efficient conductive porous structure, as well as excellent dynamic thermal regulation performances by manipulating emittance (emittance modulation of 0.39 at 8–14 μm), which could also achieve the dynamic heating or cooling of the practical object. Moreover, the performances of the device show no obvious degradation even under 650 cycles bending and 500 cycles twisting, indicating the high robustness. These results indicate that the dual-function device has promising potential for high-performance EMI shielding and thermal management applications.