Visualization of Hydrogen Evolution at Individual Platinum Nanoparticles at a Buried Interface
Rui Gao1, Martin A Edwards1, Yinghua Qiu1
1Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States.
Journal of the American Chemical Society
|April 23, 2020
Summary
Researchers used scanning electrochemical cell microscopy (SECCM) to image hydrogen evolution reactions (HER) at buried platinum nanoparticle (PtNP) electrocatalysts. Optimal HER activity occurred with a ~200 nm thick Nafion proton exchange membrane layer.
Area of Science:
- Electrochemistry
- Materials Science
- Nanotechnology
Background:
- Electrochemical interfaces are crucial for energy storage devices like fuel cells and solid-state batteries.
- Understanding interfacial activity at the nanoscale is vital for optimizing device performance.
- Buried interfaces are challenging to study with conventional electrochemical methods.
Purpose of the Study:
- To demonstrate nanoscale electrochemical imaging of reactions at buried interfaces.
- To investigate the hydrogen evolution reaction (HER) at individual platinum nanoparticles (PtNPs) beneath a proton exchange membrane.
Main Methods:
- Utilized scanning electrochemical cell microscopy (SECCM) for localized electrochemical measurements.
- Imaged the HER at individual carbon-supported PtNPs covered by varying thicknesses of Nafion (100-800 nm).
Main Results:
- Successfully achieved nanoscale electrochemical imaging of HER at a buried PtNP interface.
- HER rate at PtNPs was dependent on Nafion membrane thickness.
- Maximum catalytic activity was observed for a Nafion film thickness of approximately 200 nm.
Conclusions:
- SECCM enables direct imaging of electrochemical activity at buried interfaces.
- Nafion layer thickness significantly influences the performance of PtNP electrocatalysts for HER.
- Optimizing membrane thickness is critical for enhancing electrocatalytic efficiency in energy devices.
