In this paper, a conducting polyaniline hydrogel instead of traditional solid electrode materials is used as an electrode material to prepare high performance flexible solid-state supercapacitors. Conducting polymer hydrogels combine the properties of hydrogel with electrical conductivity, thus offering intrinsic porous conducting frameworks and promoting the transport of charges, ions, and molecules. According to our results, the capacitance of the polyaniline hydrogel electrode is quite remarkable (430 F g⁻¹) in this prototype, flexible solid-state supercapacitor with a two-electrode configuration. Furthermore, this supercapacitor shows excellent rate capability, cyclic stability and bendable performance. Moreover, this supercapacitor can drive a glow armlet to work very well, which demonstrates that the device has great potential to work as a power source in real-life applications.

In this paper, we developed a novel Zn-ion hybrid cell based on a graphene-conducting polymer composite hydrogel (capacitor-type) cathode and a zinc metal (battery-type) anode. The pseudocapacitive-type cathode materials can effectively boost the capacity of Zn-ion hybrid cell compared to that of electrical double layer cathode materials. In particular, the composite hydrogel with rational designed three-dimensional (3D) nano-architecture combining 3D porous nanostructure with hydrogel, can significantly enlarge the active interfaces between the electrode and electrolyte. According to our experiments, the 3D graphene@PANI composite hydrogel electrode exhibits a large capacity of 154 mA h g⁻¹, a superior rate capability and excellent capacity retention of 80.5% after 6000 charge–discharge cycles in a Zn-ion hybrid cell. The outstanding electrochemical properties demonstrate that the 3D nanostructure composite hydrogel materials can effectively promote the material utilization, transport of charges, and reduce the degradation of conducting polymers, leading to a highly efficient, fast and stable electrochemical process. Based on our results, Zn-ion hybrid cells based on a composite hydrogel electrode could be an extremely promising candidate for next generation electrochemical energy storage devices.