Iron induced porosity of the templated carbon for enhancement of electrochemical capacitance

Abstract

Porous carbon (PC) materials with a large specific surface area and high volume of mesopores were produced using iron-doped calcium tartrate (CaTr) as a template precursor and ethanol as a carbon source. The iron doping concentration was varied from 0.2 to 1.6 at%. Template precursor was decomposed in argon at 800 °C, the formed template nanoparticles were immediately used for chemical vapor deposition (CVD) of ethanol, and after the synthesis, they were removed by HCl treatment. It was shown that the template consisted of CaO nanoparticles 5–20 nm in size with oxidized carbon layers on the surface. The incorporation of iron into CaTr promoted graphitization of the carbon layers and led to formation of iron oxide nanoparticles 3–4 nm in size. These nanoparticles served as a replica for small mesopores in the graphitic layers obtained in the ethanol CVD process. PC materials grown on the templates with an iron doping 0.2–0.4 at% were enriched with small mesopores, and due to this, they had a surface area of 907–931 m2 g−1 and pore volume of 3.3 cm3 g−1. These materials showed the highest specific capacitances of 280–230 F g−1 at 2 mV s−1 in 1 M H2SO4 electrolyte and a good rate capability.