Electrochemical Performance of N-Doped Carbon-Based Electrodes for Supercapacitors

Capacitors are a ubiquitous component of many modern-day electronics that provide remote sensing, power conditioning, electrical noise filtering, signaling coupling or decoupling, and short-term memory storage. With the desire for flexible, smaller, and more powerful electronics, capacitors and other electrical components will have to be improved to meet these growing demands. Carbon-derived materials are good candidates for use as electrodes in electrochemical capacitors (i.e., supercapacitors) because of their nanoscale and flexible architecture. However, implementations of these materials tend to have inferior specific capacitance and energy density compared with other options. In this work, different carbon derivatives (graphene oxide, Claisen graphene, activated charcoal oxide, and activated charcoal Claisen) were chemically modified via nitrogen doping to optimize the capacitance, power density, energy density, and the overall electrochemical performance of the resulting supercapacitors. Devices with a two-electrode configuration were assembled and confirmed the superior performance for all N-doped carbon derivatives in all analyzed parameters (specific capacitance, energy density, and power density) when compared with their undoped counterparts. The maximum areal capacitance obtained was 421.44 mF/cm2 for the N-doped activated charcoal oxide, which represents an improvement of 242.2% in comparison with the corresponding nonmodified sample, in addition to a 153% improvement in the energy density and strong retention in specific capacitance (in the order of 86% at 1000 cycles of operation).