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Ammeter

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Related Experiment Video

Updated: Jun 4, 2026

Clinical Imaging of Microwave Mammography

Clinical Imaging of Microwave Mammography

Published on: November 14, 2025

The imaging ammeter.

Christopher L Wirth¹, Paul J Sides, Dennis C Prieve

¹Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA. cwirth@andrew.cmu.edu

Journal of Colloid and Interface Science

|February 15, 2011

Summary

This summary is machine-generated.

This study introduces a novel method to measure local current density using colloidal particle motion observed via microscopy. This technique offers high resolution for electrocatalyst screening without electrode segmentation.

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Area of Science:

Electrochemistry
Materials Science
Microscopy

Background:

Measuring local current density is crucial for understanding electrochemical processes.
Existing methods often require complex electrode fabrication or spatial scanning.
A need exists for simpler, high-resolution current density measurement techniques.

Purpose of the Study:

To present a new method for measuring local current density.
To demonstrate the technique's effectiveness using model electrochemical reactions.
To establish the resolution and applicability of the method for electrocatalyst screening.

Main Methods:

Utilizing an electrochemical total internal reflection microscope to observe colloidal particle motion.
Correlating particle scattering intensity and motion with local current density.
Developing a function to convert scattered light intensity to current density values.
Employing numerical simulations to validate experimental findings.

Main Results:

The method successfully measured local current density without electrode segmentation or scanning.
Spatial resolution was found to be approximately 5.7 μm, with current density resolution better than 100 nA cm⁻².
Demonstrated control of probe particle vertical motion by local current density.

Conclusions:

The developed technique provides a direct, high-resolution measurement of local current density.
This method shows promise for high-throughput screening of electrocatalysts.
The technique offers a valuable tool for electrochemical research and development.