Ultrathin PEDOT:PSS/rGO Aerogel Providing Tape‐Like Self‐Healable Electrode for Sensing Space Electric Field with Electrochemical Mechanism

Abstract A versatile composite aerogel is developed by introducing of PEDOT:PSS in reduced graphene oxide, resulting in an ultrathin aerogel film around 100 µm thick. Like a tape, the aerogel can tightly attach to smooth or rough substrate, and there forms a self‐healable and anti‐vibration energy storage electrode. With a Ti foil substrate, the electrode offers an electrochemical capacity of 190 mF cm⁻² at 0.1 mA cm⁻² working current density. It also exhibits 98.7% capacitance retention after 10 000 charge/discharge cycles, with almost negligible capacitance decline even after eight damaging/healing cycles or 4000 vibrating cycles. With symmetrical aerogel‐based electrodes, a smart electrochemical device is explored as a sensor for sensitively detecting space electric field strength, ranging from 1100 to 19 000 V m⁻¹. Simulation results verify that the response current in the sensor comes from the internal recombination current in the electrochemical device, which originates from ion recombination near the electrode substrate in space electric field. Further, a validation sensor experiment is designed and realized with affiliated modules, successfully monitoring space electric field.