Fig. 5: Surface wettability analysis of the membranes.

Water contact angles in air and underwater oil contact angles on the surface of the various membranes (a) p-CM, (b) CLGO-N-CM, and (c) OD-CLGO-N-CM. d Histograms show the water contact angles (blue color) and underwater oil contact angles (red color) on the surfaces of the membranes. The water and underwater oil contact angles were measured using the 5 µl drop of liquid.