Tuning pore structure of polymer-derived carbon materials for supercapacitor electrode materials using microscopic phase separation engineering

Abstract

Specific surface area and pore structure have critical impact on the performance of carbon-based supercapacitors. However, for carbon materials, the association between pore architecture and electrochemical performance remains unclear. In this study, sub-nano porous carbon materials with precisely controllable pore size were fabricated by a simple direct carbonization method using interpenetrating polymer networks (IPN), Besides, the correlation between pore architecture and electrochemical performance was explored by controlling the relative content of the two polymer phases to enhance or weaken the degree of microscopic phase separation so as to modulate the pore structure. C-IPN1 exhibited the highest Specific Surface Area (SSA) at 827 m2 g−1, where micropores contributed 95.8 % for the total SSA. Within the three-electrode device, C-IPN1 provided an excellent Specific Capacitance of 238.5 F g−1 at the current density of 0.5 A g−1, which had high cycle stability (100 % capacity retention for 10,000 cycles) and achieved 79.5 % capacitance retention for 20-fold increase in current density (0.5 A g-1 to 10 A g−1). Furthermore, assembled symmetrical supercapacitors achieved an energy density of 7.31 Wh Kg−1 at the power density of 62.5 W Kg−1. This could provide a new avenue for the development of high-performance carbon electrode materials for double layer capacitors, given its simple synthesis process and excellent performance.