Embodiments include an electrode material including a plurality of cores fused to a plurality of redox active linkers via Aza units to form a layered two-dimensional (2D) Aza-fused pi-conjugated covalent organic framework (COF). Embodiments also include a negative electrode material including the electrode material, as well as a supercapacitor device and an asymmetric supercapacitor device including the electrode material. Embodiments further include a method of making an electrode material including one or more of the following steps: combining a hexaketocyclohexane compound and an aromatic tetraamine compound in a solution; mixing the solution including the hexaketocyclohexane compound and the aromatic tetraamine compound; and heating the mixed solution to form a 2D Aza-fused pi-conjugated COF.