Original Micrographs.zip

Electrically non-conducting wood-based and -derived materials often suffer from charging artifacts in scanning electron microscopy (SEM). Ionic liquids (ILs) can dissipate the excess charges but have not replaced conventional coatings. In this study, we addressed the lack of low-cost options and attention to true nanoscale features by applying 1-ethyl-3-methylimidazolium methane sulfonate ([EMI][MeSO₃]) to different wood-based and -derived materials. Aqueous IL treatment of microcrystalline cellulose (MCC) improved the visibility of the particles and surface microfibrils and simplified sample preparation compared to gold and carbon coatings. Tailored IL solutions restored topographic contrast without significantly altering the surface morphology of sugar maple sawdust and pinecone scales. Imaging at 1 kV on treated samples revealed more nanoscale features than at the standard 5 kV. The IL treatment outperformed variable-pressure SEM in spatial resolution and signal-to-noise ratio. This convenient and affordable method can benefit rapid, high-resolution, and high-fidelity SEM imaging of non-conducting materials.