Polystyrene‐MOF‐Derived 3D Hierarchical Porous Carbon for High‐Performance Supercapacitors

The ability to tailor surface area, porosity, and morphologies has driven extensive research into the synthesis of metal‐organic frameworks derived carbons and their applications in energy storage. This study presents the development of three‐dimensional hierarchically porous carbon derived from polystyrene and small‐sized zeolitic imidazolate framework‐8 (ZIF‐8) particles. Incorporating nanometer‐sized ZIF‐8 particles forms a core‐shell structure in the pre‐carbonization stage, transforming into a porous carbon material with a range of pores from micro to macropores after carbonization. The carbonized material's electrode demonstrates a high capacitance of 428.8 F g‐1 at 1 mV s‐1 in the three‐electrode setup and a very high specific energy of 48.75 Wh kg‐1 at 50 mA g‐1 in the packed flat cell configuration. This exceptional electrochemical performance is attributed to the composite carbon material's high surface area, well‐developed pore structure, and self‐doped nitrogen content.