Iron Nanoparticles Wrapped with an N-Doped Carbon Material Produced by Using a Zinc Hydroxide Ferrocyanide Nanohybrid for Use in Commercial-like Supercapacitors

According to the technology of carbon-based supercapacitors,modifyingthe structure of carbon as an active electrode material leads to anincrease in capacitance. A modification involves introducing heteroatomssuch as nitrogen into the carbon structure and composing it with metalssuch as iron. In this research, an anionic source called ferrocyanidewas used to produce N-doped carbon consisting of iron nanoparticles.In fact, ferrocyanide was located as a guest between the layers ofa host material, which is zinc hydroxide in the alpha phase. Thisnew nanohybrid material was then heat-treated under Ar, and the heatedproduct after acid washing was iron nanoparticles wrapped with N-dopedcarbon materials. This material was used as an active material inthe production of symmetric supercapacitors with different organic(TEABF(4) in acetonitrile) and aqueous (sodium sulfate) electrolytesas well as a new electrolyte (KCN in methanol). Accordingly, the supercapacitormade by the N/Fe-carbon active material and the organic electrolyteshowed a capacitance value of 21 F/g at a current density of 0.1 A/g.This value is comparable to and even higher than the values observedin commercial supercapacitors.