Compton scattering imaging of liquid water in porous carbon-based materials

Abstract

Synchrotron-based Compton scattering imaging with intense high-energy X-rays allows the visualization of light element substances in an electrochemical device under an operando condition. In this study, we apply this imaging technique to a water-contained, porous carbon-based composite, which is used as a material for the gas diffusion layer in polymer electrolyte fuel cells. Analyses of the two-dimensional intensity images of Compton scattered X-rays provide the cross-sectional distributions of liquid water, as well as the depth dependency of the water content. In addition, the analyses reveal a significant interaction between the carbon materials and water droplets.