Synthesis, Characterization, and Modeling of a Functional Conjugated Microporous Polymer: CO₂ Storage and Light Harvesting

Rationalization of structure and properties of amorphous porous solids at the microscopic level is essential in developing advanced materials. We delineate the structural modeling of a designed tetraphenylethene-based amorphous conjugated microporous polymer TPE-CMP (<b>1</b>) and its gas storage and photophysical properties. The polymer <b>1</b> exhibits high specific surface area of 854 m²/g. <b>1</b> showed appreciable CO₂ (32.4 wt %) uptake at 195 K up to 1 atm and 31.6 wt % at 273 K up to 35 bar. The structural model of <b>1</b> obtained through computational methods is quantitatively consistent with experimental observations. The microporous structural model of <b>1</b> was further validated by a calculation of CO₂ adsorption isotherm obtained through GCMC simulations. Quantum chemical calculations were employed to understand the nature of interactions of CO₂ with the constituents of the framework <b>1</b>. π–π interaction with strength of 19 kJ/mol was observed between CO₂ and the phenyl rings of TPE. <b>1</b> shows strong turn-on greenish-yellow emission due to the restriction of phenyl ring rotation of TPE node. This framework induced emission (FIE) of microporous polymer <b>1</b> is further exploited for light-harvesting applications by noncovalent encapsulation of a suitable acceptor dye, rhodamine B (RhB), in the framework