N‐doped Mesoporous Carbon Loaded Co Nanoparticles as Highly Effective Non‐noble Metal Electrocatalysts Towards Oxygen Reduction Reaction in Alkaline Solution

Abstract

Developing non-noble metal electrocatalysts with low cost and advanced catalytic performance for oxygen reduction reaction (ORR) is of great significance for the largescale commercial application of fuel cells. In this work, an Ndoped mesoporous carbon supported Co nanoparticle (Co/ NC) has been innovatively designed by a facile pyrolysis method with a nitrogen-containing organic ligand as nitrogen and carbon sources by forming a complex with Co 2 + to prevent the aggregation of Co nanoparticles during the carbonization process. The Co/NC exhibits excellent electrocatalytic ORR activity, including a positive redox peak potential (0.78 V), onset potential (0.90 V), and half-wave potential (0.78 V) with electron transfer number approximately of 4.02. Co/NC performs long-term stability and has a stronger tolerance to methanol than 20% Pt/C. Furthermore, the calculated Bader charges and the charge density differences clearly demonstrate the strong metal-support interaction (SMSI) for Co/NC catalyst, which induces the change of electron structure on the Co/NC surface and is conducive to enhancing its catalytic performance. The outstanding ORR activity of Co/NC is ascribed to its unique property of prompt electron transfer, large specific surface area, and synergistic effect between Co nanoparticles and NC substrates.