High electrolyte uptake of MXene integrated membrane separators for Zn-ion batteries

The recent development of separators with high flexibility, high electrolyte uptake, and ionic conductivity for batteries have gained considerable attention. However, studies on composite separators with the aforementioned properties for aqueous electrolytes in Zn-ion batteries are limited. In this research, a polyacrylonitrile (PAN)/bio-based polyurethane (PU)/Ti(3)C(2)T(x) MXene composite membrane was fabricated using an electrospinning technique. Ti(3)C(2) MXene was embedded in fibers and formed a spindle-like structure. With Ti(3)C(2)T(x) MXene, the electrolyte uptake and ionic conductivity reached the superior values of 2214% and 3.35 × 10(−3) S cm(−1), respectively. The composite membrane presented an excellent charge–discharge stability when assembled in a Zn//Zn symmetrical battery. Moreover, the developed separator exhibited a high flexibility and no dimensional and structural changes after heat treatment, which resulted in the high-performance separator for the Zn-ion battery. Overall, the PAN/bio-based PU/Ti(3)C(2)T(x) MXene composite membrane can be potentially used as a high-performance separator for Zn-ion batteries.