▎ 摘　　要

NOVELTY - Activated expanded graphite oxide comprises at least one dopant. USE - The activated expanded graphite oxide is useful in a monolayer graphene sheet and an electrode (all claimed) of an ultracapacitor. ADVANTAGE - The activated expanded graphite oxide exhibits increased capacitance relative to undoped activated microwave expanded graphite oxide and monolayer graphene. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: (1) producing the activated expanded graphite oxide, comprising exposing a graphite oxide to at least one of microwave energy and/or thermal energy to provide an expanded graphite oxide, contacting the expanded graphite oxide with an activator, and heat treating the activated expanded graphite oxide in the presence of one or more gaseous or liquid sources of one or more dopant elements; (2) a monolayer graphene sheet comprising one or more dopant elements, where the graphene is produced by chemical vapor deposition, and the dopant atoms are incorporated into the planar molecular lattice of the graphene sheet; and (3) synthesizing graphene comprising one or more dopant elements, comprising loading a metal substrate into a chemical vapor deposition apparatus, heating the metal substrate to a temperature of 400-1400 degrees C, providing hydrogen gas while maintaining the temperature of the substrate, and providing a gaseous carbon source and at least one gaseous source of the dopant elements through the chemical vapor deposition apparatus while maintaining the temperature of the substrate.