Reinforced polyaniline-dodecyl benzene sulfonate hydrogel with well-aligned fibrous morphology as durable electrode materials for Zn-ion battery

Conducting polymer hydrogels (CPHs) are appealing organic electrode materials, and their morphology controlled synthesis and the applications in new energy-storage devices are urgently needed to be developed. Herein, based on the self-assembly between polyaniline (PANI) and anionic surfactants, sodium dodecyl benzene sulfonate (SDBS) and sodium dodecyl sulfate (SDS), a new kind of conducting polymer hydrgoels (PANI-SDBS and PANI-SDS) were synthesized. Depending on the conjugated benzene ring in SDBS, the resultant PANI-SDBS exhibited well-aligned fibrous morphology and reinforced mechanical strength. For the first time, the CPHs were employed as cathode materials for Zn-ion battery. The results showed that the three-dimensionally (3D) continuous microstructures of hydrogels could facilitate doping/dedoping kinetics and rate performance of electrodes. Moreover, well-aligned fibrous morphology endowed PANI-SDBS with excellent cycling stability (81.7% of capacity retention after 1500 discharge/charge cycles at 0.5 A g–1). This work presents a facile method to regulate the microstructures of CPHs and opens a window for their application in durable electrode materials for Zn-ion battery.