A Carbocationic Triarylmethane-Based Porous Covalent Organic Network

Abstract

A thermally stable carbocationic covalent organic network (CON), named RIO-70 was prepared from pararosaniline hydrochloride, an inexpensive dye, and triformylphloroglucinol in solvothermal conditions. This nanoporous organic material has shown a specific surface area of 990 m² g^-1 and pore size of 10.3 Å. The material has CO₂ uptake of 2.14 mmol g^-1 (0.5 bar), 2.7 mmol g^-1 (1 bar), and 6.8 mmol g^-1 (20 bar), the latter corresponding to 3 CO₂ molecules adsorbed per pore per sheet. It is shown to be a semiconductor, with electrical conductivity (σ) of 3.17×10^-7 S cm^-1 , which increases to 5.26×10^-4 S cm^-1 upon exposure to I₂ vapor. DFT calculations using periodic conditions support the findings.

Keywords: carbocation; covalent organic network; dye; porous materials.