Metanolün Elektrokimyasal Yükseltgenmesi İçin Pt katalizör Destek Malzemesi Olarak Tiyofen Kullanımı

Yıl 2022, , 812 - 818, 31.03.2022

Sadaf Adhami , Evrim Hür

https://doi.org/10.31590/ejosat.1083344

Cited By: 1

Öz

Bu çalışma da, doğrudan metanol yakıt hücrelerinde kullanılmak üzere modifiye elektrot sistemleri hazırlanmıştır. Hazırlanan elektrot sistemlerinin metanol oksidasyonuna ait elektrokimyasal davranışlarını incelemek için dönüşümlü voltametri (CV), kronoamperometri (CHR), ve elektrokimyasal empedans spektroskopisi (EIS) yöntemleri kullanılmıştır. Çalışma elektrotu olarak kalem ucu grafit (KUG) kullanılmıştır. KUG elektrotun yüzeyinde tiyofenin (Th) susuz ortamda CV yöntemi ile elektropolimerizasyonu için gerilim aralığı, tarama hızı, döngü sayısı ve asit derişimi optimizasyonları yapılmıştır. Daha sonra katalizör olarak polimer filmin üzerine platin (Pt) 4 faklı derişimde (3, 3,25, 3,50 ve 3,75mM) katkılanmıştır. Hazırlanan modifiye elektrot sistemlerinin metanol oksidasyonuna ait elektrokimyasal davranışları araştırılıp yorumlanmıştır. Bununla birlikte çalışmada kullanılan modifiye elektrot sistemlerinin SEM-EDS analizleri yapılarak polimer filmlerin morfolojik yapıları hakkında ve filmlere katkılanan Pt miktarları ile ilgili bilgi edinilmiştir. İletken polimer filmi ve Pt metanol oksidasyonu için ayrı ayrı katalizör olarak kullanıldıklarında alınan cevaplar hemen hemen benzerdir. Ancak iletken polimer Pt için destek malzeme olarak kullanıldığında, oldukça yüksek metanol oksidasyon performansı göstermektedir. CV ve EIS yöntemleri kullanılarak yapılan analizler sonucu elde edilen verilerden yararlanılarak modifiye elektrotların elektrokimyasal aktif yüzey alan (ECSA) ve spesifik kapasitans (Cs) değerleri hesaplanmıştır. Hesaplanan en yüksek ECSA ve Cs değerleri sırasıyla 1,17 m2/gr ve 0,21 Fg-1olup KUG/3,50mMPt@PTh elektroduna aittirler.

Anahtar Kelimeler

Metanol oksidasyonu, Pt, Politiyofen, İletken polimer, Elektrokimyasal oksidasyon, Yakıt hücresi

Destekleyen Kurum

Eskişehir Osmangazi Üniversitesi

Proje Numarası

2019-2990

Teşekkür

Bu araştırma tez çalışması kapsamında Eskişehir Osmangazi Üniversitesi Bilimsel Araştırma Proje birimi tarafıdan (2019-2990) desteklenmiştir. Araştırmaların yürütülebilmesinde gerekli olan kimyasal ve cam malzemelerin alınmasında sundukları maddi kaynak için BAP birimine teşekkürlerimizi sunarız.

Use Of Thiophene As Pt Catalyst support Material For Elektrochemical Oxidation Of Methanol

Öz

In this study, modified electrode systems were prepared to be used directly in methanol fuel cells. To examine the electrochemical behavior of the modified electrode systems for methanol oxidation, cyclic voltammetry (CV), chronoamperometry (CHR), and electrochemical impedance spectroscopy (EIS) methods were used. Pencil tip graphite (KUG) used as the working electrode. Optimizations of voltage range, scanning speed, number of cycles and acid concentration in anhydrous medium, were made for electropolymerization of thiophene (Th) on the surface of the KUG electrode by CV method.
Then, platinum (Pt) as a catalyst, was doped on the polymer film at 4 different concentrations (3, 3.25, 3.50 and 3.75mM). The electrochemical behavior of the modified electrode systems for methanol oxidation was investigated and interpreted. In addition, SEM-EDS analyzes of the modified electrode systems which used in the study were performed to be informed about the morphological structures of the polymer films and the amount of Pt doped to the films. Based on the results; when the conductive polymer film and Pt are used as catalyst separately for methanol oxidation, the responses are almost similar. However, when conductive polymer used as a support material for Pt as catalyst, it exposes very high methanol oxidation performance. The electrochemical active surface area (ECSA) and specific capacitance (Cs) values for the modified electrodes were calculated using the data obtained from the results of CV and EIS methods. The highest calculated ECSA and Cs values are 1.17 m2/gr and 0.21 Fg-1, respectively, and belonging to the KUG/3.50mMPt@PTh electrode.

Anahtar Kelimeler

Methanol oxidation, Pt, Polythiophene, Conductive polymer, Electrochemical oxidation, Fuel cell.

Proje Numarası

2019-2990

Kaynakça

• Kamarudin, S. K., Achmad, F., & Daud, W. R. W. (2009). Overview on the application of direct methanol fuel cell (DMFC) for portable electronic devices. International Journal of hydrogen energy, 34(16), 6902-6916.
• Andújar, José Manuel, and Francisca Segura. "Fuel cells: History and updating. A walk along two centuries." Renewable and sustainable energy reviews 13.9 (2009): 2309-2322
• Verma, L. K. (2000). Studies on methanol fuel cell. Journal of power sources, 86(1-2), 464-468.
• Spătaru, T., Marcu, M., Preda, L., Osiceanu, P., Moreno, J. M. C., & Spătaru, N. (2011). Platinum–polytyramine composite material with improved performances for methanol oxidation. Journal of Solid State Electrochemistry, 15(6), 1149-1157.
• Zainoodin, A. M., S. K. Kamarudin, and W. R. W. Daud (2010). Electrode in direct methanol fuel cells." International Journal of Hydrogen Energy, 35.10 (2010): 4606-4621
• Moussa, M., El-Kady, M. F., Zhao, Z., Majewski, P., & Ma, J. (2016). Recent progress and performance evaluation for polyaniline/graphene nanocomposites as supercapacitor electrodes. Nanotechnology, 27(44), 442001.
• Kiliç, R., Hür, E., & Arslan, A. (2017). Poly (1, 5-diaminonaphthalene) films for supercapacitor electrode materials: effect of electropolymerization technique on specific capacitance. Chemical Papers, 71(7), 1311-1321.
• Arslan, A., Hür, D., & Hür, E. (2019). Novel poly (2-(6-(5-oxo-4-(thiophen-2-ylmethylene)-4, 5-dihydrooxazol-2-yl) naphthalen-2-yl)-4-(thiophen-2-ylmethylene) oxazol-5 (4H)-one): Synthesis, electrochemical polymerization and characterization of its super capacitive properties. Synthetic Metals, 257, 116166.
• Hür, E., Varol, G. A., & Arslan, A. (2013). The study of polythiophene, poly (3-methylthiophene) and poly (3, 4-ethylenedioxythiophene) on pencil graphite electrode as an electrode active material for supercapacitor applications. Synthetic Metals, 184, 16-22.
• Arico, A. S., Cretı̀, P., Modica, E., Monforte, G., Baglio, V., & Antonucci, V. (2000). Investigation of direct methanol fuel cells based on unsupported Pt–Ru anode catalysts with different chemical properties. Electrochimica Acta, 45(25-26), 4319-4328.
• Surampudi, S., Narayanan, S. R., Vamos, E., Frank, H., Halpert, G., LaConti, A. N. T. H. O. N. Y. B., ... & Olah, G. A. (2003). Advances in direct oxidation methanol fuel cells. In Across Conventional Lines: Selected Papers of George A Olah Volume 2 (pp. 1226-1234).
• Breiter, M. W. (1967). On the nature of reduced carbon dioxide. Electrochimica Acta, 12(9), 1213-1218.
• Lee, J. S., Han, K. I., Park, S. O., Kim, H. N., & Kim, H. (2004). Performance and impedance under various catalyst layer thicknesses in DMFC. Electrochimica acta, 50(2-3), 807-810.
• Raghuveer, V., & Manthiram, A. (2005). Mesoporous carbons with controlled porosity as an electrocatalytic support for methanol oxidation. Journal of the Electrochemical Society, 152(8), A1504.
• Weidlich, C., Mangold, K. M., & Jüttner, K. (2005). EQCM study of the ion exchange behaviour of polypyrrole with different counterions in different electrolytes. Electrochimica Acta, 50(7-8), 1547-1552.
• Kitani, A., Akashi, T., Sugimoto, K., & Ito, S. (2001). Electrocatalytic oxidation of methanol on platinum modified polyaniline electrodes. Synthetic metals, 121(1), 1301-1302.
• Liu, F. J., Huang, L. M., Wen, T. C., & Gopalan, A. (2007). Large-area network of polyaniline nanowires supported platinum nanocatalysts for methanol oxidation. Synthetic Metals, 157(16-17), 651-658.
• Kost, K. M., Bartak, D. E., Kazee, B., & Kuwana, T. (1988). Electrodeposition of platinum microparticles into polyaniline films with electrocatalytic applications. Analytical Chemistry, 60(21), 2379-2384.
• Rajesh, B., Thampi, K. R., Bonard, J. M., Mathieu, H. J., Xanthopoulos, N., & Viswanathan, B. (2003). Conducting polymeric nanotubules as high performance methanol oxidation catalyst support. Chemical communications, (16), 2022-2023.
• Baldauf, M., & Preidel, W. (1999). Status of the development of a direct methanol fuel cell. Journal of Power Sources, 84(2), 161-166.
• Chen, Y. X., Miki, A., Ye, S., Sakai, H., & Osawa, M. (2003). Formate, an active intermediate for direct oxidation of methanol on Pt electrode. Journal of the American Chemical Society, 125(13), 3680-3681.
• Zhu, Y., Uchida, H., Yajima, T., & Watanabe, M. (2001). Attenuated total reflection− Fourier transform infrared study of methanol oxidation on sputtered Pt film electrode. Langmuir, 17(1), 146-154.
• Herrero, E., Chrzanowski, W., & Wieckowski, A. (1995). Dual path mechanism in methanol electrooxidation on a platinum electrode. The Journal of Physical Chemistry, 99(25), 10423-10424.
• Wu, G., Li, L., & Xu, B. Q. (2004). Effect of electrochemical polarization of PtRu/C catalysts on methanol electrooxidation. Electrochimica Acta, 50(1), 1-10.
• Domínguez-Domínguez, S., Arias-Pardilla, J., Berenguer-Murcia, Á., Morallón, E., & Cazorla-Amorós, D. (2008). Electrochemical deposition of platinum nanoparticles on different carbon supports and conducting polymers. Journal of Applied Electrochemistry, 38(2), 259-268.
• Li, S. M., Wang, Y. S., Yang, S. Y., Liu, C. H., Chang, K. H., Tien, H. W., ... & Hu, C. C. (2013). Electrochemical deposition of nanostructured manganese oxide on hierarchically porous graphene–carbon nanotube structure for ultrahigh-performance electrochemical capacitors. Journal of power sources, 225, 347-355.
• Prabakar, S. R., Kim, Y., Jeong, J., Jeong, S., Lah, M. S., & Pyo, M. (2016). Graphite oxide as an efficient and robust support for Pt nanoparticles in electrocatalytic methanol oxidation. Electrochimica Acta, 188, 472-479.
• Chen, Z., Xu, L., Li, W., Waje, M., & Yan, Y. (2006). Polyaniline nanofibre supported platinum nanoelectrocatalysts for direct methanol fuel cells. Nanotechnology, 17(20), 5254.
• Snook, G. A., Kao, P., & Best, A. S. (2011). Conducting-polymer-based supercapacitor devices and electrodes. Journal of power sources, 196(1), 1-12.