Nitrogen Doping on Carbon Paper Electrodes

Carbon papers are widely used as electrode materials for electrochemical applications, include but not limited to; flow batteries, fuel cells, supercapacitors, sensors, and bioelectrochemical systems. In order to increase the hydrophilicity of carbon paper, and hence improve the electrochemical properties, one of the common approaches is to incorporate oxygen containing functional groups when heating in air at relatively elevated temperature, resulting in increases of the wetting properties of carbon paper and improve the electrochemical performance. As our work demonstrate here, this approach is not ideal, especially when dealing with electrochemical system that contain high acid concentration or are sensitive to hydrogen peroxide production from oxygen reduction. We provided here a simple alternative approach via a pre-physiochemical treatment to successfully prepare a nitrogen-doped carbon paper that reduces the in-situ H 2 O 2 production and at the same time, remarkably increases the electrochemical activity of the electrode. Characterisation using Raman spectroscopy for the prepared N-doped graphite paper indicates higher defects in structure that fit well with XPS and BET analyses and provide explanation of many interfacial charge transfer observations. For example, VO 2 + /VO 2+ and [Fe(CN) 6 ] 4−/3− redox couples show with the N-doped carbon paper a superior catalytic activity compared to other preheated or bare carbon papers could be obtained. Thus, the prepared N-doped carbon paper, can provide alternative promising electrode material which is suitable for higher efficiency for various electrochemical applications.