Abstract: A composite with high energy storage capacity for use in energy storage devices includes graphene and mesoporous graphitic carbon nitride (mc@g-C3N4). The graphitic carbon nitride is coated on mesoporous carbon (mc@g-C3N4) at a concentration ranging from 3% to 33%. The graphitic carbon nitride is obtained from condensation of mesoporous carbon and urea or a precursor thereof. Electrodes may be prepared from the composite. High energy high power storage devices such as the Electric Double Layer Capacitor (EDLC) may be fabricated with these electrodes.