Flexible 3D porous MnOx/rGO hydrogel with fiber reinforced effect for enhancing mechanical and zinc storage performances

3D Porous MnO x /rGO hydrogel (3DP MnO x /rGO hydrogel) as cathode material for aqueous zinc ion batteries (AZIBs) is synthesized by polyvinyl alcohol (PVA), nanowires of MnO x (NW MnO x ) and reduced graphene oxide (rGO) via repeated freeze-thaw method, which has a high flexibility and puncture resistance. The 3D self-supporting hydrogel presented complex 3D cross-linking system and excellent flexibility through hydrogen bonding and reinforcement of inorganic nano wires. The electrochemical and mechanical properties of the 3DP MnO x /rGO hydrogel are optimized by adjusting the respective percentages of NW MnO x (30%), rGO (5%), PVA (25%), and H 2 O (40%) in the total mass. The flexible hydrogel cathode exhibits a high capacity of 297.6 mA h g −1 and good cyclic stability after 500 cycles at 1 A g −1 . Finite element method confirms that the hydrogel material can alleviate the stress distribution caused by zincification process. The soft-packaged AZIBs, which utilize 3DP MnO x /rGO hydrogel as the cathode and Zn foil as the anode, exhibit excellent cycling performance (152.2 mA h g −1 at 1 A g −1 after 500 cycles under an angle of 180°) and provide a stable power supply across different bending angles.