Polycarbazole and biomass-derived flexible nitrogen-doped porous carbon materials for gas adsorption and sensing

Abstract

Carbazole-based porous organic polymers (CPOPs) and their derived carbon materials have been found to be promising candidates for many applications, such as gas adsorption and energy storage, due to their highly porous structure and nitrogen-containing functionalities. However, most of the reported CPOPs or CPOP-derived carbons are powder-like materials, which limit their industrial applications. Hereby, flexible nitrogen-doped porous carbon materials (FNPCs) were synthesized through in situ oxidative coupling polymerization in/on flexible biomass textiles and subsequent carbonization procedures. During the carbonization procedure, the microporous structure and the nitrogen in CPOPs were maintained. The CPOP-derived FNPCs possess good flexibility and relatively large specific surface area and pore volume, together with high nitrogen contents. In light of these merits, gas adsorption, separation, and preliminary sensing experiments were conducted. The carbon dioxide and methane adsorption capacities of the FNPC are 21.0 wt% and 3.5 wt% (at 273 K and 1.0 bar), respectively. Meanwhile, due to the interaction between CO₂ and the FNPCs, the materials can also be used for CO₂/N₂ separation and gas sensing, and a preliminary experiment on FNPC as a gas sensor for exhaled breath was conducted. More importantly, the materials are flexible and they can be easily assembled into gas adsorption devices and sensors.