Truxene/triazatruxene-based conjugated microporous polymers with flexible@rigid mutualistic symbiosis for efficient CO2 storage

Conjugated microporous polymers (CMPs), with rigid pi-conjugated skeletons and tunable microporous structure, have shown great potential as gas storage and sequestration materials, however, the inherent poor solubility of initial building block in the polymerization process always leads to low crosslinking polymers and limited application. Here, in this work, we have designed the flexible@rigid mutualistic symbiosis in two series of CMPs (2D extend truxene and triazatruxene cores, P-C(-Et) and P-N(-Et). The results demonstrated that rational flexible groups with additional rigid skeletons structure could change the 2D C-3 symmetric building core into 3D steric configuration, which increased the target polymers' BET surface areas more than 3 times and narrowed the microporous width. The optimized molecule structure delivers a high CO2 uptake ability, 5.8-11.5 wt% for truxene, and 7.8-17.6 wt% for triazatruxene at 273 K and 1.0 bar. Besides, the optimized structures also have superior selectivity of CO2 when the N-2 or CH4 still exists in the system. In conclusion, this work provides a fundamental understanding for the design of CMPs for high CO2 adsorption and separation performances.

Automated summary

This work designed two series of CMPs with flexible@rigid mutualistic symbiosis, which changed the 2D C-3 symmetric building core into a 3D steric configuration by combining rational flexible groups with additional rigid skeletons structure, leading to increased BET surface areas and narrowed microporous width for target polymers, resulting in enhanced CO2 uptake ability.