High Throughput Correlative Electrochemistry-Microscopy Analysis on a Zn-Al Alloy

Area of Science:

• Electrochemistry
• Materials Science
• Surface Science

Background:

• Electrode and electrocatalyst performance is influenced by complex compositional and structural features.
• Understanding how these microstructural motifs impact electrochemical activity is crucial for material design.

Purpose of the Study:

• To investigate the electrochemical activity of microstructural features on Zn-Al alloy surfaces.
• To correlate local composition and structure with electrochemical behavior using advanced microscopy and voltammetry.

Main Methods:

• Voltammetric Scanning Electrochemical Cell Microscopy (SECCM) for spatially resolved electrochemical measurements.
• Correlative Energy-Dispersive X-ray Spectroscopy (EDS) mapping for high-resolution elemental composition analysis.
• High-throughput electrochemical screening of over 651 distinct sites on Zn-Al alloy surfaces.

Main Results:

• The α-phase Zn-Al was identified as favoring metal dissolution (oxidation) and electrochemical reduction processes like the oxygen reduction reaction (ORR).
• High Al content (30-50%) in the nanospot α-phase correlates with local Al dissolution during ORR in unbuffered media.
• Structure-composition heterogeneity significantly impacts local electrochemical activity on complex electrode surfaces.

Conclusions:

• SECCM combined with EDS provides critical insights into the structure-electrochemical activity relationships of complex alloys.
• These findings are essential for the rational design of next-generation electromaterials with tailored properties.
• The study highlights the importance of microstructural analysis for optimizing electrode performance in applications like batteries and cathodic protection.