Compressed Sensing Image Reconstruction of Scanning Electrochemical Microscopy Measurements Carried Out at Ultrahigh...

Area of Science:

• Electrochemistry
• Surface Science
• Imaging Techniques

Background:

• Scanning electrochemical microscopy (SECM) with continuous line probes (CLPs) offers faster imaging than conventional ultramicroelectrode (UME) methods.
• Increasing CLP scan speed improves imaging rates but degrades image quality due to electrolyte transport effects.

Purpose of the Study:

• To investigate the application of compressed sensing (CS) postprocessing for CLP-based SECM.
• To determine if CS can enable high-quality imaging at scan rates exceeding conventional limits.

Main Methods:

• CLP-SECM measurements were performed at varying probe scan rates.
• Compressed sensing algorithms were applied as a postprocessing technique to reconstruct images.
• Image quality was systematically evaluated across different scan rates, characterized by Péclet numbers (Pe).

Main Results:

• CS postprocessing successfully reconstructed high-fidelity CLP-SECM images even at greatly increased scan rates.
• Accurate image reconstruction was achieved for Péclet numbers approaching 5, an order of magnitude higher than conventional SECM.
• This demonstrates a new upper bound for CLP scan speeds, limited by the onset of chaotic convective flows.

Conclusions:

• Compressed sensing is a powerful tool for enhancing the speed of SECM imaging with CLPs.
• CS allows SECM to surpass the conventional speed limit, enabling faster electrochemical analysis.
• Understanding hydrodynamic effects is crucial for designing future high-speed SECM probes.