POP-1

The separation of chemical substances with analogous chemical structures and physical properties remains a great challenge. In this work, triptycene-like microporous organic polymers (MOPs), POP-1, was synthesized via choosing 1,4-dimethoxybenzene (DMB) and triptycene as external cross-linkers and building blocks, respectively, and POP-1 was employed to separate xylene isomers and benzene (Bz)/cyclohexane (Cy). Results show that POP-1 has a higher uptake for m-xylene (0.29 g/g) and Bz (1.02 g/g); more intriguingly, their complete separation can be realized within 0.6 min using a column packed with POP-1. The interaction between POP-1 networks and adsorbates was also investigated using theoretical (density functional theory together with noncovalent interaction analysis) and experimental (inverse gas chromatography) approaches. Especially, both results present a good agreement, that is, weak interactions such as CH/π interactions play a dominant role in defining the separation performance of POP-1 for xylene isomers and Bz/Cy mixtures. Our findings suggest that MOPs may open up a new route for separating the chemicals that are similar in structure and size.

In the present work, a novel porous, and chemically stable amine-based covalent organic polymer (POP-1) was designed and synthesized under solvothermal conditions. The porosity, crystallinity, chemical stability, electrochemical properties, and diffuse reflectance of POP-1 were investigated via N₂ sorption experiment, power X-ray diffraction, thermogravimetric analysis, cyclic voltammetry, and ultraviolet visible near infrared spectrometry, respectively. POP-1 exhibits good chemical stability in both acidic and alkaline aqueous solutions, as well as in organic solvents. Undoped POP-1 can be directly used as a photocatalyst for rhodamine B irradiation degradation under light-emitting diode and natural light. The E_a of POP-1 for RhB degradation is 82.37kJ/mol. Furthermore, POP-1 can be reused as a catalyst in RhB degradation without degraded catalytic activity.