Efficient CO Capture Using Nitrogen-Enriched Microporous Carbon Derived from Polybenzoxazine in a Single-Step Process for Environmental Sustainability.

In this research, we successfully synthesized nitrogen-enriched microporous carbon through a meticulous process involving two different activation procedures. Initially, polybenzoxazine was carbonized at 800 °C to create a precursor material, which was then activated with two different activating agents (KOH and KMnO) at the same temperature. This activation significantly enhanced the material's porosity, increasing its specific surface area from 335 m/g (KOH activated) to 943 m/g (KMnO activated). XPS analysis confirmed the presence of nitrogen functionalities, including secondary-N, oxide-N, pyridone-N, and pyridine-N, which are critical for CO adsorption. Adsorption tests demonstrated a high CO uptake of 3.8 mmol/g at 25 °C and 1 bar, driven by a combination of physisorption (physical interaction with the surface area) and chemisorption (chemical interaction with nitrogen sites). This high adsorption capacity can be attributed to the carbon's substantial surface area, significant micropore volume, and the interconnected network of pores, which together provide structural stability and facilitate the diffusion of CO molecules. These findings suggest that this nitrogen-enriched microporous carbon, derived from polybenzoxazine, holds significant promise as a highly efficient material for applications in CO capture and storage.