Electronic nature of linkers-based conjugated microporous polymers: a sustainable approach to enhance CO2 capture†
Abstract
Conjugated microporous polymers (CMPs) represent a promising class of materials with diverse applications due to their unique chemophysical characteristics. We introduce a novel approach for developing a TPPDA–TPA CMP- and TPPDA–ThZ CMP-based dynamic tetraphenyl-p-phenylenediamine (TPPDA) unit employing the optimum conditions for the Suzuki protocol. These CMPs incorporate triphenylamine (TPA) and 4,7-di(thiophen-2-yl)benzo[c]thiadiazole (ThZ), and exhibit distinct electronic properties. Our CMPs demonstrate high thermal durability (char yield up to 69.5 wt%) and significant surface areas (up to 132 m2 g−1). The TPPDA–TPA CMP shows a notable presence of nucleophilic bonding sites, enhancing the selective uptake of CO2, with around twofold-higher CO2 uptake (27.49 cm3 g−1) compared with TPPDA–ThZ CMP (14.67 cm3 g−1). Additionally, we evaluate the selectivity of CO2 over N2 gases on TPPDA CMPs. We analyze CO2 uptake based on key thermodynamic and kinetic principles, including the Clausius–Clapeyron equation and Henry's law. This research offers a promising strategy for enhancing CO2-adsorption capacities on CMPs.