One-Step Preparation Pitch-Based Porous Carbon Via Carbonization and Co-Activation for High-Performance Supercapacitors

Hierarchical porous carbon (HPC) material for supercapacitor (SC) application is synthesized via a one-step carbonization and activation method, using a novel composite activating agent with synergistic activation effect from mesophase pitch (MP) as precursor. The obtained mesophase pitch-based porous carbon (MPPC) exhibits an ultra-high specific surface area of 2955.0 m2 g-1, well-controlled pore size distribution, and exceptional electrochemical performance. The specific capacitance of MPPC-4 reaches up to 338.1 F g-1 at 1 A g-1 and maintains at 250.1 F g-1 even at 20 A g-1, demonstrating excellent rate capability. Furthermore, the assembled symmetric supercapacitor achieves a high energy density of 29.83 Wh kg-1 at a power density of 999.93 W kg-1 and still maintains 6.56 Wh kg-1 at a high power density of 19.89 kW kg-1. Additionally, the supercapacitor exhibits good cyclic stability with a capacitance retention rate of 88.55% after 5000 cycles. This novel composite activating agent provides an efficient and creative approach for the preparation of pitch-based porous carbon electrode materials.