Fig. 4From: Porous polymers bearing functional quaternary ammonium salts as efficient solid catalysts for the fixation of CO2 into cyclic carbonatesSEM images of a, c DVB-HTA and b DVB-BTA; EDS elemental mapping of d Br element, e O element, and f N element; and TEM images of g DVB-HTA and h DVB-BTABack to article page