Porous carbon materials was synthesized using MCM-41as template and self–N–doped porous carbon material was fabricated via a well–directed synthesized 1–butyl–3–methylimidazolium triazole [Bmim]tr, an exemplary ionic liquid (IL) possessing 36.4 wt % N content and dual–aromatic anion/cation. The obtained materials had well–distributed hierarchical meso–/micro–pore structure, a large surface area (1425.6 m² g⁻¹), and high N content (11.29 wt%), which provided efficient electron transmission capability, thus significantly enhancing the electrochemical performance. At 1.0 A g⁻¹, the specific capacitance from the CN₉₀₀ sample achieved 376.4 F g⁻¹. In addition, a high energy density of 13.07 Wh kg–1 at 500 W kg–1 was demonstrated. Furthermore, a high stability of more than 97.7% after 10,000 cycles was obtained. This study presents that the dual–aromatic cation/anion–based ILs with high N–content/MCM–41 template strategy is promising for the preparation of self–N–doped carbon materials for supercapacitor applications.