Conductive cross-section preparation of non-conductive painting micro-samples for SEM analysis

• Published in: Scientific reports Vol. 12; no. 1; p. 19650
• Main Authors: Jaques, Victory Armida Janine, Zikmundová, Eva, Holas, Jiří, Zikmund, Tomáš, Kaiser, Jozef, Holcová, Katarína
• Format: Journal Article
• Language: English
• Published: England Nature Publishing Group 16.11.2022; Nature Publishing Group UK; Nature Portfolio
• Subjects: Chemical composition; Cross-sections; Cultural heritage; Curing; Epoxy resins; Light microscopy; Morphology; Protective coatings; Scanning electron microscopy
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-022-21882-1

Scanning electron microscopy (SEM) is a common method for the analysis of painting micro-samples. The high resolution of this technique offers precise surface analysis and can be coupled with an energy-dispersive spectrometer for the acquisition of the elemental composition. For light microscopy and SEM analysis, the painting micro-samples are commonly prepared as cross-sections, where the micro-sample positioned on the side is embedded in a resin. Therefore, the sequence of its layers is exposed after the cross-section is polished. In common cases outside of cultural heritage, a conductive layer is applied on the polished side, but in this field, the measurements are mostly done in low-vacuum SEM (LV-SEM). Although the charging effect is reduced in LV-SEM, it can still occur, and can hardly be prevented even with carbon tape or paint. This work presents two conductive cross-section preparation methods for non-conductive samples, which reduce charging effects without impairing the sample integrity.