Graphene-based aerogels have garnered signi cant 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 speci c 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 speci c surface area (2030 m 2 g -1 ) and pore volume (5.4 cm 3 g -1 ). Given its intriguing properties, CNGA demonstrates good performance as a gas adsorbent and sulfur host.