Sub-3 nm Pt@Ru toward Outstanding Hydrogen Oxidation Reaction Performance in Alkaline Media
Fei Yang1,2,3, Yian Wang2, Yingdan Cui2
1Eastern Institute for Advanced Study, Eastern Institute of Technology, Ningbo 315200, Zhejiang, China.
Journal of the American Chemical Society
|December 6, 2023
Summary
Researchers developed sub-3 nm Pt@Ru core-shell nanoparticles using a simple impregnation method. These advanced electrocatalysts significantly boost hydrogen oxidation reaction kinetics for anion-exchange membrane fuel cells (AEMFCs).
Area of Science:
- Materials Science
- Electrochemistry
- Nanotechnology
Background:
- Anion-exchange membrane fuel cells (AEMFCs) are promising for hydrogen conversion but face challenges due to slow hydrogen oxidation reaction kinetics in alkaline media.
- Developing efficient electrocatalysts is crucial for advancing AEMFC technology.
Purpose of the Study:
- To synthesize highly active and stable sub-3 nm Pt@Ru core-shell nanoparticles.
- To improve the hydrogen oxidation reaction kinetics in AEMFCs.
- To demonstrate a facile synthesis method for advanced nanocatalysts.
Main Methods:
- Utilized a simple impregnation process to sequentially reduce platinum (Pt) and ruthenium (Ru) at different annealing temperatures, creating Pt@Ru core-shell nanoparticles.
- Characterized the synthesized nanoparticles' size, structure, and electrochemical surface area (ECSA).
- Evaluated electrocatalyst performance using rotating disk electrode (RDE) measurements and membrane electrode assembly (MEA) tests.
Main Results:
- Synthesized ultrasmall Pt@Ru core-shell nanoparticles with an average size of ~2.5 nm and a high ECSA of 166.66 m² gPt+Ru-1.
- Achieved exchange current densities (j0) 8.0 and 5.8 times higher than commercial Pt/C, with the mass-normalized j0 being the highest reported to date.
- Demonstrated a peak power density of 1.78 W cm-2 in MEA tests, surpassing commercial PtRu/C.
Conclusions:
- The simple impregnation method is effective for synthesizing fine Pt@Ru core-shell nanocatalysts.
- The enhanced activity is attributed to electron transfer from Ru to Pt and the ultrafine particle size.
- This work highlights the potential of core-shell nanostructures for improving AEMFC performance and the importance of atomic structure control.
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