Abstract
Nuclear magnetic resonance is one of therare techniques able to probe selectively the ions inside thenanoporous network in supercapacitor devices. With amagnetic resonance imaging method able to detect all ions(adsorbed and nonadsorbed), we record one-dimensionalconcentration profiles of the active ions in supercapacitorswith an electrode configuration close to that used inindustry. Larger anionic concentration changes are probedupon charge and discharge in a carbide-derived carbon(CDC) with micropores smaller than 1 nm compared to aconventional nanoporous carbon (CC) with a largerdistribution of pore sizes, up to 2 nm. They highlight theincreased interaction of the anions with CDC and provide a better understanding of the enhanced capacitance in CDC-based supercapacitors.