Cobalt oxyphosphide as oxygen reduction electrocatalyst in proton exchange membrane fuel cell

• Published in: International journal of hydrogen energy 2011, Vol.36 (1), p.720-724
• Main Authors: Wang, Meiri, Zhang, Huamin, Zhong, Hexiang, Ma, Yuanwei
• Format: Article
• Language: English
• Subjects: Alternative fuels. Production and utilization; Applied sciences; Cobalt; Cobalt oxyphosphide; Electrocatalysts; Energy; Exact sciences and technology; Fuel cells; Fuels; Hydrogen; Membranes; Nanostructure; Oxygen reduction reaction; Proton exchange membrane fuel cell; Pt-free electrocatalyst; Reduction; Stability; Wetness
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2010.09.065

The cobalt oxyphosphides supported on carbon black were prepared using incipient wetness method and characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The possibility of their application as the electrocatalyst for oxygen reduction reaction (ORR) in proton exchange membrane fuel cell (PEMFC) was investigated and the electrocatalytic activities were evaluated by the electrochemical measurements and single cell test, respectively. The electrocatalyst presents attractive catalytic activity towards ORR and good stability in acid media and exhibits an onset potential for oxygen reduction as high as 0.69 V (RHE) in H 2SO 4 solution. The maximum power density obtained in a H 2/O 2 PEMFC is 57 mW cm −2 with Co 4P 2O 9/C loading of 1.13 mg cm −2. No significant performance degradation is observed over 50 h of continuous fuel cell operation. The combination of heteroatom P with nanostructured oxides with high stability, excellent functionality and low cost which are prerequisites for large-scale applications, probably provide a new solution for the critical challenge of finding effective cathode materials for PEMFC.