Constructing ionic porous organic polymers with high specific surface area through crosslinking strategy.

Ionic porous organic polymers with high surface area and desirable ionic density are obtained by crosslinking strategy and these polymers have shown remarkable catalytic performance for the cycloaddition reaction of CO 2 with epoxides under mild conditions. [Display omitted] • Crosslinking strategy is proposed to improve the specific surface area of IPOPs. • IPOP1-XL and IPOP2-XL are successfully synthesized by crosslinking strategy. • IPOP1-XL and IPOP2-XL both possess excellent porosity and preferable ionic density. • IPOP1-XL shows remarkable catalytic performance in CO 2 chemical fixation. Ionic porous organic polymers (IPOPs) emerge as porous networks with charged characteristics for versatile applications. However, most of the reported IPOPs have suffered from poor porosity due to the presence of electric charges in the synthesis process. Until now, it is a challenge to obtain IPOPs with both great porosity and high ionic density. Herein, we demonstrate a simple crosslinking strategy to integrate large specific surface area and abundant ionic sites in IPOPs (named as IPOPs-XL). Especially, IPOP1-XL synthesized via crosslinking strategy exhibits a large Brunauer–Emmett–Teller (BET) specific surface area of 1830 m2 g−1, which is 18 times higher than that of the pyridine-based polymer before crosslinking (IPOP-1, 96 m2 g−1). The uptake capacity for carbon dioxide (CO 2) of IPOP1-XL (11.7 wt%) is also much higher than that of IPOP-1 (4.5 wt%) at 273 K due to the enhanced porosity. Meanwhile, IPOP1-XL also possesses an improved ionic density (3.5 mmol g−1), which plays a pivotal role in CO 2 chemical fixation. This work provides a feasible method to improve the porosity of IPOPs. [ABSTRACT FROM AUTHOR]