Scanning Acoustic Microscopy for Quantifying Two-phase Transfer in Operando Alkaline Water Electrolyzer

Improved understandings of two-phase transport in electrochemical gas-evolving systems are increasingly demanded, while high-performance imaging techniques using simplified instrumentations are not readily available. This work presents volumetric scanning acoustic microscopy (SAM) imaging for quanti...

Full description

Saved in:
Bibliographic Details
Published in:arXiv.org 2024-05
Main Authors: Dou, Zehua, Rox, Hannes, Ramos, Zyzi, Baumann, Robert, Ravishankar, Rachappa, Czurratis, Peter, Yang, Xuegeng, Andrés Fabian Lasagni, Eckert, Kerstin, Czarske, Juergen, Weik, David
Format: Article
Language:English
Subjects:
Acoustic microscopes
Bubbles
Electrodes
Electrolysis
High resolution
Image resolution
Imaging techniques
Residual gas
Scanning acoustic microscopy
Spatial distribution
Wettability
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Improved understandings of two-phase transport in electrochemical gas-evolving systems are increasingly demanded, while high-performance imaging techniques using simplified instrumentations are not readily available. This work presents volumetric scanning acoustic microscopy (SAM) imaging for quantifying the dynamics of gas bubbles and electrolyte in porous Nickel electrodes with different wettability and structures during alkaline water electrolysis (AWE). We realize high-resolution 3D imaging at 10's um level using high frequency spherically focused ultrasound. The high resolution allowed us to clearly visualize the spatial distributions of produced bubbles in the porous electrodes over time. Moreover, we are able to quantify the residual gas volume in an electrode and its coverage due to bubble evolution, which dominate its transport overpotential. Taking these advantages, we elucidate the impacts of electrodes' wettability and structures on their electrolysis performance, on a regular laboratory base. The obtained knowledge provides us important optimization guidelines of AWE designs and operating schemes.
ISSN:2331-8422