Modification of Vulcan XC-72 for Enhanced Durability of PEMFC Catalyst Layer

Öz

AbstractA series of SiO2 modified Vulcan XC-72 support materials were prepared to investigate the effect of silica modification on the durability of the catalysts layer of Polymer Exchange Membrane Fuel Cells (PEMFC). XRD, TGA, BET, DLS, EDX and TEM were used to examine structural and microstructural properties. The performance of the catalysts layers were evaluated using a single cell operating at 60˚C under fully humidified H2 and O2 purge. Electrochemical Impedance Spectroscopy (EIS) experiments were carried out to observe the impedance behavior of the MEAs. The MEAs were cycled between 0.6V to 1.2V for 24 hours at 20 mV/s (1440 cycles) under hydrogen and nitrogen purge to conduct Accelerated Durability Tests (ADTs). The modification of Vulcan XC-72 was found to be an effective way to improve both the performance and the durability of the catalyst. The MEA with 22.9 wt% SiO2 content showed 13 times less performance loss than that of the MEA prepared with commercial catalyst after ADTs.

Anahtar Kelimeler

• Fuel cells, Catalysts durability, Pt-Co

Kaynakça

1. Bezerra, C. W. B., Zhang, L., Liu, H. S., Lee, K. C., Marques, A. L. B., Marques, E. P., Wang, H. J., and Zhang, J. J., 2007, "A review of heat-treatment effects on activity and stability of PEM fuel cell catalysts for oxygen reduction reaction," Journal of Power Sources, 173(2), pp. 891-908.
2. Sayin, E. S., Bayrakceken, A., and Eroglu, I., 2012, "Durability of PEM fuel cell electrocatalysts prepared by microwave irradiation technique," International Journal of Hydrogen Energy, 37(21), pp. 16663- 16672.
3. Liu, D., and Case, S., 2006, "Durability study of proton exchange membrane fuel cells under dynamic testing conditions with cyclic current profile," Journal of Power Sources, 162(1), pp. 521-531.
4. Zhang, S. S., Yuan, X. Z., Hin, J. N. C., Wang, H. J., Friedrich, K. A., and Schulze, M., 2009, "A review of platinum-based catalyst layer degradation in proton exchange membrane fuel cells," Journal of Power Sources, 194(2), pp. 588-600.
5. Zhang, S. S., Yuan, X. Z., Wang, H. J., Merida, W., Zhu, H., Shen, J., Wu, S. H., and Zhang, J. J., 2009, "A review of accelerated stress tests of MEA durability in PEM fuel cells," International Journal of Hydrogen Energy, 34(1), pp. 388-404.
6. Cheng, X., Shi, Z., Glass, N., Zhang, L., Zhang, J. J., Song, D. T., Liu, Z. S., Wang, H. J., and Shen, J., 2007, "A review of PEM hydrogen fuel cell contamination: Impacts, mechanisms, and mitigation," Journal of Power Sources, 165(2), pp. 739-756.
7. Cheng, X., Zhang, J. L., Tang, Y. H., Song, C. J., Shen, J., Song, D. T., and Zhang, J. J., 2007, "Hydorgen crossover in high temperature PEM fuel cells," Journal of Power Sources, 167(1), pp. 25-31.
8. Watanabe, M., Tsurumi, K., Mizukami, T., Nakamura, T., and Stonehart, P., 1994, "Activity and Stability of Ordered and Disordered Co-Pt Alloys for Phosphoric- Acid Fuel-Cells," Journal of The Electrochemical Society, 141(10), pp. 2659-2668.

9. Akita, T., Taniguchi, A., Maekawa, J., Siroma, Z., Tanaka, K., Kohyama, M., and Yasuda, K., 2006, "Analytical TEM study of Pt particle deposition in the proton-exchange membrane of a membrane electrode- assembly," Journal of Power Sources, 159, pp. 461- 467.
10. Wu, J. F., Yuan, X. Z., Martin, J. J., Wang, H. J., Zhang, J. J., Shen, J., Wu, S. H., and Merida, W., 2008, "A review of PEM fuel cell durability: Degradation mechanisms and mitigation strategies," Journal of Power Sources, 184(1), pp. 104-119.
11. Mitsushima, S., Kawahara, S., Ota, K. I., and Kamiya, N., 2007, "Consumption rate of Pt under potential cycling," Journal of The Electrochemical Society, 154(2), pp. B153-B158.
12. Knights, S. D., Colbow, K. M., St-Pierre, J., and Wilkinson, D. P., 2004, "Aging mechanisms and lifetime of PEFC and DMFC," Journal of Power Sources, 127(1-2), pp. 127-134.
13. Chen, Y. G., Wang, J. J., Liu, H., Li, R. Y., Sun, X. L., Ye, S. Y., and Knights, S., 2009, "Enhanced stability of Pt electrocatalysts by nitrogen doping in CNTs Communications, 11, pp. 2071-2076. cells," Electrochemistry
14. Dundar, F., Uzunoglu, A., Ata, A., and Wynne, K. J., 2012, "Durability of carbon-silica supported catalysts for proton exchange membrane fuel cells," journal of Power Sources, 202, pp. 184-189.
15. Pinchuk, O. A., Dundar, F., Ata, A., and Wynne, K. J., 2012, "Improved thermal stability, properties, and electrocatalytic activity of sol-gel silica modified carbon supported Pt catalysts," International Journal of Hydrogen Energy, 37(3), pp. 2111-2120.
16. Huang, Q., Yang, H., Tang, Y., Lu, T., and Akins, L. D., nanoparticles electrochemistry Communications, 8, pp. 1220-1124. reduction reaction,"
17. Xu, Y., Ruban, V. A., and Mavrikakis, M., 2004, "Adsorption and dissociation of O2 and Pt-Co and Pt- Fe alloys," J Am Chem Soc, 126, pp. 4717-4725.
18. Antolini, E., Salgado, J. R. C., and Gonzalez, E. R., 2006, "The stability of Pt-M (M=first raw transition metal) alloy catalysts and its effect on the activity in low temperature fuel cells A literature review and tests on a Pt-Co catalyst," Journal of Power Sources, 160, pp. 957-968.
19. Santiago, E. I., Varanda, L. C., and Villullas, H. M., 2007, "Carbon-supported Pt-Co catalysts prepared by a modifled polyol process as cathodes for PEM fu el cells," Journal of Physical Chemistry C, 111(7), pp. 3146-3151.
20. Sattler, M., and Ross, P. N., 1986, "THE SURFACE- STRUCTURE SUPPORTED ON CARBON-BLACK AND THE RELATION REDUCTION," Society, 133(8), pp. C300-C300.
21. PT-CRYSTALLITES TO ACTIVITY of Journal the Electrochemical
22. Peuckert, M., Yoneda, T., Betta, R. A. D., and Boudart, M., 1986, "OXYGEN REDUCTION ON SMALL SUPPORTED PLATINUM PARTICLES," Journal of the Electrochemical Society, 133(5), pp. 944-947.
23. Travitsky, N., Ripenbein, T., Golodnitsky, D., Rosenberg, Y., Burshtein, L., and Peled, E., 2006, "Pt- , PtNi- and PtCo-supported catalysts for oxygen reduction in PEM fuel cells," Journal of Power Sources, 161(2), pp. 782-789.
24. Takenaka, S., Hirata, A., Tanabe, E., Matsune, H., and Kishida, M., 2010, "Preparation of supported Pt- Co alloy nanoparticle catalysts for the oxygen reduction reaction by coverage with silica," Journal of Catalysis, 274(2), pp. 228-238.
25. Uzunoglu, A., Dundar, F., and Ata, A., 2011, "C-SiO2 supported catalysts for durability and performance improvement electrochemical Society Transactions, 41(1), p. 1257.