Controlled thermal decomposition of aromatic polyethers to attain nanoporous carbon materials with enhanced gas storage

Abstract

Reported is the development of nanostructured synthetic carbon materials that have been synthesized by thermal-decomposition of aromatic rich polyethers: poly(ether ether ketone) (PEEK) and poly(2,6-dimethyl-1,4-phenylene oxide) (PPO). These polymer based nanostructured carbons are efficacious for gas adsorption and storage and have Brunauer–Emmett–Teller (BET) surface areas of more than 3000 m² g⁻¹, and average pore diameters of ≤20 Å. Surface area, pore characteristics, and other critical variables for selecting porous materials of high gas adsorption capacities are presented. Analysis of the fragments evolved under various carbonization temperatures, and the correlation between the activation and carbonization temperatures provides a mechanistic perspective of the pore evolution during activation. Correlations between gas (N₂ and H₂) adsorption capacity and porous texture of the materials have been established. The materials possess excellent hydrogen storage properties, with hydrogen storage capacity up to ∼7.0 wt% (gravimetric) and ∼42 g H₂ L⁻¹ (volumetric) at −196 °C and 4.5 MPa.