Carbon supported platinum catalysts for proton exchange membrane fuel cell (PEMFC) applications have been studied intensively in the scientific community.^1,2 The catalytic activity of the catalyst depends on the characteristics of the carbon support material³ and on the Pt depositing method^4,5. The aim of the study was to investigate the oxygen reduction reaction (ORR) on Pt nanoparticles deposited on peat-derived carbon. The Pt nanoparticles were deposited on the carbon support material by three different methods using NaBH₄ (NBH), ethylene glycol (EG) and isopropyl alcohol (IA) as a reducing agent.

The studied materials were characterized using N₂ sorption, X-ray diffraction (XRD) and thermogravimetric analysis (TGA). Structure of the platinum nanocatalyst on carbon support was also studied using scanning electron microscopy with energy-dispersive X-ray analysis (SEM-EDX). For electrochemical characterization, the electrochemically active surface area (ECA) of the materials were measured in a three-electrode system (0,1 M HClO₄) and in a completed PEMFC. The ORR kinetics of the materials were studied by the rotating disk electrode (RDE) method as well as in a PEMFC configuration.

As a result, it was found that the higher the ECA of the material, the higher the catalytic activity. The catalytic activity of the synthesized materials increases in order: IA < NBH < EG. ECA of the materials increases in the same order. Also, the special surface area of the materials increases in the same order. The catalytic activities of the synthesized materials were compared to a commercial catalyst material, 60% Pt on HSA Ketjenblack.

References

1. O. Z. Sharaf and M. F. Orhan, Renew. sust. energ. rev., 32, 810–853 (2014).
2. Y. Wang, K. S. Chen, J. Mishler, S. C. Cho, and X. C. Adroher, Appl. Energ., 88, 981–1007 (2011).
3. S. Sharma and B. G. Pollet, J. Power Sources, 208, 96–119 (2012).
4. S. Sepp et al., Electrochim. Acta, 203, 221–229 (2016).
5. P. Valk et al., J. Electrochem. Soc., 165, F315–F323 (2018).

Acknowledgements

The author thanks the 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) and the Estonian Energy Technology Program: SLOKT10209T “. Nanomaterials – research and applications (NAMUR)” project 3.2.0304.12-0397. The author also thanks the private limited company AuVe Tech.