The promotion of electrode active materials with higher rate capabilities and lower cost has been a long-standing challenge in the field of supercapacitors. In this work, a novel composite of asphalt with graphene oxide is developed, and it is found that the introduction of a small amount of graphene oxide such as 1 wt% could increase conductivity up to ∼400% and surface area up to ∼114%. The composite materials without the addition of any conducting material demonstrate both high capacitance and cycling stability. In addition, their rate capability is well maintained from 0.5 A g−1 to 100 A g−1 with high capacitance retention (∼88%). Furthermore, the optimized material, which is made mainly from the cheap waste material asphalt, demonstrates an excellent energy density (22.0 Wh kg−1) at an ultra-high power density (55.4 kW kg−1), which indicates its promising potential for industrial applications in green energy.
