Photothermal-thermoelectric composite film with excellent self-healing and low temperature resistance properties for electromagnetic wave shielding and absorption

Photothermal-thermoelectric composite film rarely has been designed as high-performance electromagnetic wave (EMW) shielding and absorbing materials with desirable ability of solar energy utilization, and the harsh environment resistance of the film has never been elucidated. Herein, excellent photothermal-thermoelectric polydimethylsiloxane/single-walled carbon nanotube@Fe 3 O 4 film is assembled for the first time, owning superior EMW attenuation, self-healing and low temperature resistance by synergistically manipulating multiple factors, such as compositions, structures and morphologies. It is found that the optimized composite film delivered a strong absorption of −60.8 dB with an effective absorption band of 3 GHz (8.2–11.2 GHz) and small thickness (2.79 mm) in X-band, while single-walled carbon nanotube with extremely low content of 0.08 wt% and prepared nanocage-like Fe 3 O 4 are employed to compound with polydimethylsiloxane matrix. And noticeable photothermal effect and thermoelectric effect with p/n-type are simultaneously acquired via adjusting the contents of single-walled carbon nanotube, along with flexible hot-press/photo/electro-driven self-healing and low temperature resistance of −19.7 °C, making it the only indirect solar power generation EMW absorption material by photothermal and thermoelectric effect with extreme environmental tolerance. In short, this work expounds on constructing a unique highly efficient absorbing material with the capability of solar energy utilization and outstanding comprehensive performance. • Excellent photothermal-thermoelectric composite film is assembled by a facile ultrasonic-assisted mechanical stirring together with hot-press processes. • The film has a satisfactory electromagnetic wave absorption ability with Min. RL of −60.8 dB and EAB of 3 GHz (8.2–11.2 GHz) at 2.79 mm. • The highest .|SRL l | and |SRL lt | values of 603 and 216 are achieved. • There is a clear logical relationship among sunlight, heat, electricity and self-repairability of film.