2.2. Preparation of UiO-66 and UiO-66-NH2 Nanofibers

Through a solvothermal method, UiO-66 as well as UiO-66-NH2 powders were formed according to our previous studies. Briefly, a mixture of ZrCl₄ (1.68 g), H₂BDC (0.96 g), DMF (40 mL), and 4 mL of 37% HCl were heated at 80 °C for 8 h to afford UiO-66. Following reaction completion, mixture was centrifuged, followed by frequent washing using DMF and twice with ethanol to eliminate residual DMF. For UiO-66-NH₂ synthesis, ZrCl₄ (0.63 g) as well as 2-aminoterephthalic acid (0.68 g) were dissolved in DMF and then 1 mL of 37% HCl was added to obtain more crystals. After heating at 80 °C with stirring for 7 h, followed by cooling, the collected product was washed using DMF and ethanol (twice), and then dried in the oven overnight.

For preparing nanofibers derived from UiO-66 and UiO-66-NH₂, PVDF and different loadings of MOF powders (10, 20, and 40 wt.%) were dissolved in DMF, followed by stirring at 40 °C for 6 h. The CNMs were electrospun on a flat aluminum foil at 0.3 mL h⁻¹ flow rate 15 kV, and 20 cm distance between the needle and collector. After electrospinning process completion, the composites were left to dry at 60 °C in an oven for 3 h to remove residual solvent.