Nitrogen precursor effects in iron-nitrogen-carbon oxygen reduction catalysts

Metal-nitrogen-carbon (MNC) cathode catalysts were synthesized using nitrogen precursors of varying NitrogenCarbon (NC) ratio by pyrolysis in a constant volume reaction vessel. Here, we demonstrate that increasing a key property, the NC ratio of the nitrogen precursor increased the accessible active site density by reducing carbon deposition in the pores of the carbon support during pyrolysis. The most active catalysts were obtained in this work using melamine, having a NC ratio of 2. Kinetic current density as high as 13 A cm-3 at 0.8 ViR-free and over 100 h of stable current at 0.5 V were observed with melamine based MNC catalysts. \ua9 2011 The Electrochemical Society.Peer reviewed: YesNRC publication: Ye