Zeolitic imidazolate framework-8 modified poly(vinylidene fluoride-co-hexafluoropropylene)/polyacrylonitrile composite separators for Li-ion batteries

As one of the most stable MOFs, zeolitic imidazolate framework-8 (ZIF-8) has been widely studied for applications in the field of energy storage, catalysis, and environment protection. In this paper, ZIF-8 was employed to enhance the electrochemical properties and thermal stability of the electrospun poly(vinylidene fluoride-co-hexafluoropropylene)/polyacrylonitrile (PVDF-HFP/PAN) composite separator. The results indicate that the test cells assembled with the composite separators show improved rate capability, high discharge capacity, and stable cycling performances. The addition of ZIF-8 can improve the affinity of PVDF-HFP/PAN toward liquid electrolytes, and further enhance the ionic conductivity of the composite separators. In addition, the thermal stability of the PVDF-HFP/PAN separator has been improved by ZIF-8 nanoparticles. This work can provide insight into the application of MOF materials in Li-ion batteries.