Porous graphene with high porosity derived from nitrogen-doped graphene aerogel for vapor adsorption and lithium–sulfur batteries

Abstract

Graphene-based aerogels have garnered significant attention due to their combined advantages derived from both graphene and aerogels. Nevertheless, a key limitation in their practical applications arises from their relatively modest specific surface area and pore volume. In this study, porous graphene materials with high porosity are synthesized through the physical and chemical activation of nitrogen-doped graphene aerogel (NGA) using carbon dioxide and KOH as activating agents. Utilizing various characterization techniques, including scanning electron microscopy, nitrogen adsorption–desorption measurements, and X-ray photoelectron spectroscopy, the morphology, porous characteristics, and chemical composition of porous graphene are elucidated. The carbon dioxide-activated NGA (CNGA) maintains the spongy aerogel structure and exhibits a hierarchical porous structure encompassing micropores, mesopores, and macropores. Notably, CNGA exhibits a high specific surface area (2030 m2 g–1) and pore volume (5.4 cm3 g–1). Given its intriguing properties, CNGA demonstrates good performance as a gas adsorbent and sulfur host.