Viologen Salt Bridge‐Equipped Ionic Covalent Organic Polymers Directed toward Anionic Adsorption

The well‐defined porosity architectures and distinct charge characteristics of ionic covalent organic polymers (ICOPs) have garnered significant attention as promising candidates for drug delivery, adsorption, separation, and gas collection and storage applications. This study reports the synthesis of two novel ICOPs, TPE‐COP and PY‐COP, based on tetraphenylethene and pyrene cores, respectively, with viologen serving as the conjugated bridge. To complement the experimental findings and provide microscopic insights into the adsorption mechanism, density functional theory calculations are performed. Results indicate that the PY‐COP model exhibits a more planar structure compared to TPE‐COP, explaining the observed morphological variations: spherical for TPE‐COP and stacked morphology for PY‐COP. TPE‐COP exhibits markedly stronger stabilization toward oxoanions. Saturated adsorption capacities are determined for both ICOPs against selected anionic pollutants, demonstrating competitive performance compared to existing adsorbents. For KMnO 4 , TPE‐COP and PY‐COP demonstrate capacities of 0.77 and 0.35 g MnO 4 − g −1 , respectively. Similarly, for Na 2 Cr 2 O 7 , the saturated adsorption capacities are 0.17 g Cr 2 O 7 2− g −1 for TPE‐COP and 0.06 g Cr 2 O 7 2− g −1 for PY‐COP. These results demonstrate the superior adsorption performance of TPE‐COP compared to PY‐COP, highlighting the influence of structural design on adsorption efficacy.