Nitrogen-doped carbon aerogels derived from polyimide for high-performance supercapacitor

Carbon aerogels have attracted increasing interest as electrode material and conductive template for supercapacitors due to their unique porous structure and strong electrical conductivity. However, the satisfactory strategy for fabricating carbon aerogels with excellent electrochemical performance remains to be explored. Herein, polyimide aerogels with porous fibrous networks were successfully synthesized by ambient pressure drying, and nitrogen-doped carbon aerogel were obtained after high-temperature processing by using the polyimide aerogel as the precursor. The pore structure of carbon aerogel was controlled by adjusting the repeat unit of polyimide molecular chain. When the repeat unit was 60 and carbonization temperature was 800 °C, PA-60-800 exhibits a typical honeycomb porous structure, which contains numerous meso-micro-porosity and provides a large specific surface area > 1000 m2 g−1. In addition, PA-60-800 showed excellent electrochemical behavior with the specific capacitance of 314.1 F g−1 at 0.5 A g−1. After 10,000 cycles of galvanostatic cycling, the electrode still maintains a capacity retention of 98.8%. Moreover, PA-60-800-assembled symmetric supercapacitor display a high energy density of 23 Wh kg−1 at a power density of 535.8 W kg−1. This work proposes an alternative path for the preparation of high-performance nitrogen-doped carbon aerogel electrode materials.