*2.3. Preparation of RCMs*

The RCMs were prepared via the electrospinning method. First, the mixed solution with contents of 10 wt% (PAN) and 1 wt% (RPMs) was prepared by adding PAN (2.0000 g) and RPMs (0.2000 g) into DMSO (20 mL) under continuous magnetic stirring at 85 ◦C for 2.5 h. The mixed solution was extracted 10 mL by using a 10 mL disposable syringe and then the composite membranes were prepared by electrostatic spinning. Electrospinning was carried out at a temperature of 25 ± 5 ◦C, humidity of 30 ± 5%, the fixed voltage of 20 KV, feeding rate of 0.1 mL/h and a distance of 16 cm. Electrospinning was stopped after 10 h. Finally, RCMs were obtained after methanol extraction for 24 h and vacuum dried at 60 ◦C for 12 h. The scheme for preparing the RCMs was represented in Figure 1.

**Figure 1.** The scheme for preparing the RCMs.
