Oxygen Reduction Reaction Activity of Pt and Pt-W Alloy Nanoparticles Synthesized by Spark-Discharge Generator

0558051 - ÚT 2023 RIV CZ eng A - Abstrakt
Garapati, Meenakshi Seshadhri - Němec, Tomáš
Oxygen Reduction Reaction Activity of Pt and Pt-W Alloy Nanoparticles Synthesized by Spark-Discharge Generator.
HydrogenDays 2022. Praha: The Czech Hydrogen Technology Platform (HYTEP), 2022 - (Stehlík, K.). s. 18-18. ISBN 978-80-907264-8-2.
[HydrogenDays 2022. 23.06.2022-25.06.2022, Praha]
Institucionální podpora: RVO:61388998
Klíčová slova: proton exchange membrane fuel cells * oxygen reduction reaction * catalyst nanoparticles * spark-discharge generator * rotating disk electrode
Obor OECD: Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis)
https://www.hydrogendays.cz/2022/

Proton exchange membrane fuel cells (PEMFC) are the potential candidates to convert energy stored in hydrogen into electrical energy at low temperatures with high efficiency. Nevertheless, the oxygen reduction reaction (ORR) occurring at the cathode of PEMFC limits the performance due to higher overpotential and lower kinetics of the catalysts. Moreover, the carbon material used as the support for platinum catalyst nanoparticles also undergoes corrosion at higher potentials resulting in performance degradation. Herein, carbon-free Pt and Pt-W alloy nanoparticles are synthesized by a spark-discharge generator (SDG). Two different modes of SDG operation have been applied, i.e. alternating discharge (AC) and unipolar discharge (DC), to adjust nanoparticle size and nanoalloy composition. The synthesized Pt and Pt-W nanoparticles are studied as the ORR catalysts. The crystallite properties and morphology of the synthesized catalyst nanoparticles have been analyzed by X-ray diffraction (XRD) and transmission electron microscopy (TEM), respectively. Furthermore, the ORR activity of Pt and Pt-W nanoparticles has been studied by cyclic voltammetry (CV) and rotating disk electrode (RDE) measurements in 0.1 M HClO4 electrolyte. The ORR peak potential in the CV pattern and onset potential of Pt nanoparticles obtained from AC discharges tend to be more positive than for DC mode synthesis suggesting a higher ORR activity of AC mode synthesis. Also, Pt-W alloy nanoparticles demonstrate higher ORR activity in AC mode, which paves the way to develop a new type of ORR catalysts without carbon supports.
Trvalý link: https://hdl.handle.net/11104/0337842