Preparation of Membrane Electrode Assemblies Using Waste Tire Derived Carbon Supported Platinum Catalyst

Since the world’s population and energy demand are constantly growing and energy is largely based on the use of non-renewable energy sources, it would be necessary to find an alternative, more environmentally friendly energy carrier [1]. One of the most important alternative energy carriers is hydrogen, which is used in the operation of the polymer electrolyte membrane fuel cell (PEMFC), where chemical energy is converted into electrical energy, and only heat and pure water are released during operation [2]. As the demand for means of transport is also increasing in the world, more and more old tires are generated every year (5 billion are predicted for 2030 ) [3]. Waste tires do not decompose and generally end up in landfills, which is not a sustainable solution. Therefore, opportunities are being sought for the recycling of waste tires in various fields. In this work, a Pt catalyst material is synthesized using carbon made from waste tires as a support material [4]. The aim of this work was to investigate the activity of oxygen reduction reaction (ORR) of synthesized platinum catalysts. The Pt deposition was performed by two different methods. Synthesized catalyst materials (S1 and S2) and commercial catalyst (K) for comparison were characterized physically to obtain information on Pt weight percent and Pt crystallite size, material elemental composition, specific surface area, and porosity. Catalysts were characterized electrochemically using rotating disk electrode and cyclic voltammetry methods to determine their ORR kinetics. Measurements of PEMFC performance in air showed that catalyst materials with smaller Pt crystallite size and higher ECA values also had higher ORR activity. In addition, it was found that the power density depends significantly on the carbon used in the synthesis of the Pt catalyst and the method of preparation of the membrane electrode assembly (MEA). Based on the PEMFC measurements of the optimized MEAs, the power density increased in the order S1 < S2 < K. References: [1] M.Z. Jacobson, M.A. Delucchi, Z.A.F. Bauer, S.C. Goodman, W.E. Chapman, M.A. Cameron, C. Bozonnat, L. Chobadi, H.A. Clonts, P. Enevoldsen, J.R. Erwin, S.N. Fobi, O.K. Goldstrom, E.M. Hennessy, J. Liu, J. Lo, C.B. Meyer, S.B. Morris, K.R. Moy, P.L. O’Neill, I. Petkov, S. Redfern, R. Schucker, M.A. Sontag, J. Wang, E. Weiner, A.S. Yachanin, Joule 1 (2017) 108. [2] O.Z. Sharaf, M.F. Orhan, Renew. Sustain. Energy Rev. 32 (2014) 810. [3] P. Grammelis, N. Margaritis, P. Dallas, D. Rakopoulos, G. Mavrias, Energies 14 (2021) 571. [4] G.-S. Kang, G. Lee, S.Y. Cho, H.-I. Joh, D.C. Lee, S. Lee, Appl. Surf. Sci. 548 (2021) 149027. Acknowledgements: European Union Regional Development Fund for the financial support of the project TK141 „Innovative materials and high-tech equipment for energy recovery systems“(2014-2020.4.01.15-0011) The Estonian Research Agency project (personal research support group grant project No. PRG676)