Titanium nitride–carbon nanotube core–shell composites as effective electrocatalyst supports for low temperature fuel cells

Abstract

Titanium nitride–carbon nanotube (TiN–CNT) core–shell nanocomposites were developed by a simplistic two step fabrication procedure and characterized by transmission electron microscopy, X-ray diffraction and thermogravimetric analysis. These materials were utilized as platinum nanoparticle electrocatalyst supports (Pt/TiN–CNT) for the oxygen reduction reaction (ORR) and methanol oxidation reaction (MOR), two important low temperature fuel cell processes. Improved ORR and MOR activities were demonstrated for Pt/TiN–CNTs compared with state of the art commercial Pt/C. Moreover, enhanced CO tolerance towards the MOR was demonstrated attributed to the interaction occurring between adsorbed CO molecules and the TiN–CNT supports. TiN–CNTs are thus presented as highly promising, novel electrocatalyst support materials with enhanced ORR and MOR performance attributed to their anisotropic morphology, enhanced electronic properties and conductivity, and distinct catalyst–support interactions.