Porous Organic Polymer Synthesized by Green Diazo-Coupling Reaction for Adsorptive Removal of Methylene Blue

[Image: see text] A porous organic polymer (marked as DT-POP), which contains abundant free phenolic hydroxyl groups, is synthesized by the well-known green azo-coupling reaction in water, characterized, and utilized as an effective adsorbent for the elimination of methylene blue (MB) from water solutions. The presence of permanent mesopores, abundant active functional groups, and π-electron enrichment ascribed to phenyl rings make DT-POP an efficient adsorbent for MB due to strong hydrogen bonding, π–π, and electrostatic interactions with the cationic dye MB. DT-POP with high stability and high adsorption capacity can be reused many times and thus shows high applicability in pollutant disposal.