Corrosion Resistant Electrospun Niobium Carbide Nanotube Supports for PEMFC Cathodes

Recent research has shown that metal carbides and nitrides can potentially present the required properties to replace the carbon blacks conventionally used as electrocatalyst supports in Proton Exchange Membrane Fuel Cells (PEMFC). Our aim is to associate these alternative compositions with controlled morphologies to design electronically conductive and chemically stable materials with the appropriate porosity.

Currently we are developing a range of synthesis routes leading to NbC based materials with different morphologies leading to high surface areas. For example, using a three step synthesis, we prepared hollow microspheres of niobium carbide with a surface area of 70 m² g^-1 and an electronic conductivity of 10³ S m^-1. Furthermore we are developing various syntheses leading to electrospun niobium carbide nanofibres with different porosities in order to study the influence of the morphology on surface area and electrochemical activity.

These various supports have been catalysed by deposition of platinum nanoparticles synthesised by a microwave assisted polyol method, and they have been evaluated as electrocatalyst support for the oxygen reduction reaction.

This contribution will describe the preparation of Pt on NbC-based supports and their chemical and electrochemical characterisation including cyclic corrosion tests to evaluate their stability over time compared with Pt on carbon.