PtAu Electrocatalysts.pdf

Researchers investigated chemical partitioning at crystalline defects in PtAu alloys to stabilize electrocatalysts. They found that adding 5 at.% Au to Pt can improve the stability and longevity of Pt electrocatalysts by more than an order of magnitude. The study used advanced atomic-scale material characterization methods, including high-resolution scanning transmission electron microscopy (HR-STEM) and atom probe tomography (APT), to quantify the defect types and segregation chemistry. The results showed that Au segregation at defects can protect Pt electrocatalysts from dissolution and passivate undecorated defects where dissolution is expected to initiate. The study proposes a mechanistic understanding of the dissolution process and opens up pathways to use solute segregation to defects for the atomic-scale design and synthesis of advanced, stable electrocatalysts for efficient and sustainable energy conversion and storage. Key findings include:

Au segregation at defects can improve the stability and longevity of Pt electrocatalysts
The addition of 5 at.% Au to Pt can reduce dissolution by more than an order of magnitude
Advanced atomic-scale material characterization methods can quantify defect types and segregation chemistry
The study provides a mechanistic understanding of the dissolution process and proposes a new approach to stabilize electrocatalysts.