Preparation and properties of carbon nanofiberbased cathode materials for zinc-ion battery doped with rich oxygen deficiency MnOx

Rechargeable aqueous zinc-ion batteries (ZIBs) have been widely studied because of its excellent performance, low price and environment-friendly, and the structure design of ZIBs cathode with high capacity and long cycle life have become the focus. PAN solution containing Mn(NO3)2·xH2O was used as a core layer and PAN solution as skin layer by coaxial electrospinning. Due to the concentration gradient diffusion, Mn(NO3)2·xH2O diffused to the cortex. And MCNFs with sebaceous glandular structure on the surface was obtained by carbonization. MnO2 was electrodeposited on its surface, and MnO2@MCNFs cathode with excellent affinity with electrolytes were prepared. The results show that the sebaceous gland structure not only increases the specific surface area of cathode, but also constructs the riveting effect between MCNFs and α-MnO2, which enhances the interface bonding between the substrate and the active material, reduces the shedding of α-MnO2, reduces the interface resistance, and shortens the electron conduction and ion diffusion path. The test shows that the specific capacity of the first cycle of 3% MnO2@MCNFs can reach about 581.16 mAh/g under the current density of 100 mA/g, and the specific capacity of 120 mAh/g can be maintained after 1000 cycles under the high current density of 1 A/g, and the coulomb efficiency is around 99%