A green and fast approach to nanoporous carbons with tuned porosity: UV-assisted condensation of organic compounds at room temperature

Abstract

This work reports a green and fast approach to the synthesis of nanoporous carbon materials based on the UV-assisted condensation of organic compounds as precursors. This new approach offers several improvements over the classical soft template and sol-gel routes for the synthesis of materials: versatility of organic precursors, shorter synthesis time, and ambient conditions. Owing to the specificity of the UV-assisted reactions mechanisms, organic compounds of varied chemical composition can be used as precursors in the preparation of nanoporous carbons with tuned porous features. The method consisted in the exposure of an aqueous solution of the organic precursors to UV light for 60 min at room temperature in the absence of a catalyst, allowing an outstanding shortening of the synthesis time compared to sol-gel routes. Furthermore, UV irradiation promoted the cross-linking of the polymer chains of precursors at room temperature, as opposed to classical methods that require an additional step at mild/high temperatures. By changing the chemistry of the organic compound used as precursor, it was possible to modulate the surface area (from 10 to 720 m2 g−1) and the porosity of the synthesized carbons within the micro-/mesopore range. The obtained carbons also presented varied morphology depending on the precursor, from dense aggregates to ordered hexagonal arrangements of nanometric dimensions.