Synthesis of Sub‐nanometer Porous Carbon Film for Energy Storage

Carbon‐based supercapacitors are a kind of supercapacitors with very promising applications because of their low cost, good stability and adjustable properties. Simple and rapid syntheses of carbon materials with a high surface area and narrow pore size distribution are of great significance to practical applications of carbon‐based supercapacitors. Here we report a new strategy to synthesize sub‐nanometer porous carbon films (Snp‐CF) via a condensation reaction under mild conditions. Carbon films exhibit a narrow pore size distribution (6.6 Å) and high surface area (508 m 2  g −1 ) after annealing at 700 °C. Snp‐CF‐700 displays a good specific capacity and excellent cycle performance (130 F g −1 after 5000 cycles, 118 % of initial 110 F g −1 ).