Fig. 2From: Transparent PAN:TiO2 and PAN-co-PMA:TiO2 Nanofiber Composite Membranes with High Efficiency in Particulate Matter Pollutants FiltrationMorphology of PAN:TiO2 nanofiber membranes with different spinning times (different thicknesses): a 15 min, b 30 min, c 45 min, d 1 h, e 2 h, f 4 h, g 6 h and h 8 hBack to article page