A carbon adsorbent storage and dispensing system is provided with a structurally modified particulate carbon adsorbent designed with optimal volumetric surface area for a certain range of particle sizes. Bulk density and specific surface area are carefully balanced to ensure the volumetric surface area remains within an optimal range to create high performance, as measured by dispensing capacity of the dopant fluid that is reversibly adsorbed onto the structurally modified particulate carbon adsorbent.