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Here, in-house Co N C and Fe N C have been prepared by, first, chelating the metals (Co or Fe) with ethylene diamine tetra acetic acid, known as EDTA (nitrogen precursor). UV–Visible (UV–Vis) spectrometry has been used to ensure the chelated metal formation. In the next step, the chelated metals have been deposited on a high surface area oxidized carbon support to increase the electrical conductivity. The latter composite material has been thermally treated at 800 °C (CoNC8 and FeNC8) or 1000 °C (CoNC10 and FeNC10) in nitrogen atmosphere in order to create the catalytic sites that will be able to perform the oxygen reduction reaction (ORR) in the acid medium. Electrochemical tests have been carried out to investigate the activity and durability of the electro-catalysts for the ORR. Methanol tolerance properties have been also evaluated for a possible application in direct methanol fuel cells. It appears that FeNC8 is the most active electrocatalyst in the presence of methanol in the base electrolyte, thus showing promising characteristics for direct methanol fuel cells. Instead, stability tests of these metal nitrogen catalysts indicate the best resistance to corrosion for the catalysts treated at 1000 °C. [ABSTRACT FROM AUTHOR]

Abstract: An iron-based non-precious metal (NPM) catalyst was synthesized by chemically coating a polymer containing nitrogen, such as polyaniline (PANI), on multiwalled carbon nanotubes (MWCNTs), followed by iron complexation and heat treatment in a decomposable source of nitrogen (ammonia) at high temperature. Its excellent activities for oxygen reduction reaction (ORR) in both acidic and alkaline media were confirmed by thin film rotating disk electrode technique. Also, durability test was performed in both media. After 20,000 (0.65–1.0V) potential cycles, the half-wave potential decayed by only 40mV in 0.1M HClO4, while in 0.1M KOH it gained 25mV. In addition, no activity decay was observed by adding methanol in the acidic solution indicating its excellent tolerance to methanol oxidation. [Copyright &y& Elsevier]

Abstract: Co based catalyst were evaluated for oxygen reduction (ORR) in liquid KOH and alkaline anion exchange membrane fuel cells (AAEMFCs). In liquid KOH solution the catalyst exhibited good performance with an onset potential 120mV more negative than platinum and a Tafel slope of ca. 120mVdec−1. The hydrogen peroxide generated, increased from 5 to 50% as the electrode potential decreased from 175 to −300mV vs. SHE. In an AAEMFC environment, one catalyst (GP2) showed promising performance for ORR, i.e. at 50mAcm−2 the differences in cell potential between the stable performance for platinum (more positive) and cobalt cathodes with air and oxygen, were only 45 and 67mV respectively. The second catalyst (GP4) achieved the same stable power density as with platinum, of 200 and 145mWcm−2, with air at 1bar (gauge) pressure and air (atm) cathode feed (60°C), respectively. However the efficiency was lower (i.e. cell voltage was lower) i.e. 40% in comparison to platinum 47.5%. [Copyright &y& Elsevier]