Nitrogen‐Immobilized, Ionic Liquid‐Derived, Nitrogen‐Doped, Activated Carbon for Supercapacitors

To synthesize nitrogen‐remained activated carbon (AC) following KOH activation, nitrile‐functionalized ionic liquid (IL) that immobilizes nitrogen atoms in the form of aromatic amines, such as graphitic, pyridinic, or pyrrolic nitrogen, was synthesized and used as a carbon precursor. Aromatic amines are more robust in adverse conditions than aliphatic amines. The nitrogen‐doped (N‐doped) AC was prepared by activating the carbon derived from the nitrile‐functionalized IL that acts as both a carbon precursor and a nitrogen‐doping source. The N‐doped AC had an optimized doped nitrogen and porous structure, and was prepared by controlling the activation conditions. The nitrogen residue in the N‐doped AC after KOH activation enhanced electrochemical properties of the N‐doped AC. Thus, it is important to use a carbon precursor that includes immobilized nitrogen to effectively prepare the AC after the KOH activation. Nitrile‐functionalized ionic liquid was synthesized and used as a carbon precursor to synthesize activated carbon with nitrogen residue after KOH activation. The nitrogen‐doped activated carbon (N‐doped AC) exhibits high porosity as well as high‐nitrogen content. The N‐doped AC has an optimized doped nitrogen and a porous structure, and was prepared by controlling the activation condition.