(E)-1,2-Diphenylethene-based conjugated nanoporous polymers for a superior adsorptive removal of dyes from water

Conjugated microporous polymers (CMPs) as prospective adsorbents for organic pollutant treatments are extremely appealing for both basic and applied kinds of research due to their simplicity, high performance, low cost, and processing under ambient conditions. However, the development of CMPs having excellent pollutant adsorption behaviour is still challenging. Herein, we described the targeted synthesis of a series of (E)-1,2-diphenylethene-based CMPs - BIPE-BIPE, BIPE-Py, and BIPE-TPT CMPs - via [4 + 4] and [4 + 3] Suzuki-Miyaura polymerizations of the novel (E)-1,2-bis(3,5-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)ethene (BITPE-4Bpin) with 1,2-bis(3,5-dibromophenyl)ethene (BIPE-4Br), 1,3,6,8-tetrabromopyrene (Py-4Br), and 2,4,6-tris(4-bromophenyl)-1,3,5-triazine (TPT-3Br), respectively. The porosities, chemical structures, and morphologies of the three CMPs were studied. The synthesized CMPs displayed high BET surface areas (up to 1400 m2 g-1) and outstanding thermal stabilities (up to a Td10 of 604 °C and char yield of 81 wt%). In addition, the as-prepared CMPs showed an extraordinarily high adsorption capacity for the organic dye rhodamine B (RhB) from water; the maximum adsorption capacity for RhB was 1027 mg g-1. Interestingly, our CMPs exhibited good recyclability and quickly attained 99.6% of their maximal adsorption capacity within 3 min. Our CMPs with the excellent adsorption behaviour could be good materials for water treatment and purification applications.