Last modified: 2014-10-18
Abstract
Nitrogen-doped CNTs, directly grown on a carbon cloth (CNT/CC) hybrid with polybenzimidazole (PBI), are utilized as hybrid electrodes in high-temperature proton exchange membrane fuel cells (HT-PEMFCs). The use of a rotation holder for pulse electrodepositing Pt nanoparticles (NPs) on a CNT electrode is developed herein. The electrochemical surface area of the Pt NPs/PBI-CNTs is approximately 161cm2 mg-1 and the grain size is around 8~9 nm. A comparative study of 0.09 mg cm-2 Pt NPs on a PBI–CNT (Pt/PBI–CNT) electrode and 0.8 mg cm-2 Pt NPs on PBI–carbon black (Pt/PBI–CB) for reducing oxygen at the cathode was carried out. In H2/O2 HT-PEMFC single cell tests, a low Pt-loaded (0.09 mg cm-2) Pt/PBI–CNT/CC electrode outperformed a high Pt-loaded (0.8 mg cm-2) Pt/PBI–CB/CC electrode with maximum power densities of 620 mW cm-2 and 468 mW cm-2, respectively, at 160 oC.
Keywords
References
[1] J. S.Wainright, J. T. Wang, D. Weng, R. F. Savinell, M. Litt, "Acid-doped polybenzimidazoles: A new polymer electrolyte"Journal of the Electrochemical Society, 1995, pp. L121-L123.
[2] Q. Li, R. He, J. O. Jensen, N. J. Bjerrum, "PBI-based polymer membranes for high temperature fuel cells - Preparation, characterization and fuel cell demonstration". Fuel Cells, 2004, pp. 147-159
[3] P. Ajayan, O.Zhou, Springer Berlin, Heidelberg," Applications of Carbon Nanotubes"; 2001; Vol. 80.
[4] H. Y. Du, C. H. Wang, H. C. Hsu, S. T. Chang, S. C. Yen, L. C. Chen, B. Viswanathan, K. H. Chen, ”High performance of catalysts supported by directly grown PTFE-free micro-porous CNT layer in a proton exchange membrane fuel cellJournal of Materials Chemistry", 2011pp. 2512-2516