High resolution imaging of ultrafine bubbles in water by Atmospheric SEM-CL. (November 2022)

• Record Type: Journal Article
• Authors: Inami, Wataru; Hara, Naoto; Kawata, Yoshimasa; Kobayashi, Hideaki; Fujita, Toshihiro
• Is Part Of: Micron. Volume 162(2022)
• Publication Date: 2022-11
• Subjects: Ultrafine bubbles -- Atmospheric SEM-CL -- Silicon nitride membrane -- Nanoparticle tracking analysis; Microscopy -- Periodicals; Electron Probe Microanalysis -- Periodicals; Microscopy -- Periodicals; Microscopie -- Périodiques; Microscopy; Periodicals; 502.82
• DOI: 10.1016/j.micron.2022.103351
• Languages: English
• ISSNs: 0968-4328

Abstract

Abstract: Various analytical methods such as high-resolution observation of ultrafine bubbles in water are required to clarify the mechanisms and interrelationships of various effects brought about by ultrafine bubbles. In this study, we used atmospheric scanning electron microscopy-cathodoluminescence (ASEM-CL) method for observing ultrafine bubbles in water. ASEM can observe samples in water, and the fine electron beam provides high spatial resolution. Furthermore, the gas in the bubble can be estimated from the CL emission spectrum. We have measured characteristics such as bubble size and particle number density. Also, the CL spectra has shown that the ultrafine bubbles contained nitrogen. Graphical Abstract: ga1 Highlights: Ultrafine bubbles in water were observed by atmospheric scanning electron microscope. Ultrafine bubble images were obtained by cathodoluminescence and reflected electrons. Cathodoluminescence from the ultrafine bubbles indicates that they contain nitrogen. Ultrafine bubbles in water with a diameter of about 200 nm were observed.