Probing the Cellulose-Ionic Liquids Interaction by X-ray Photoelectron Spectroscopy

X-ray photoelectron spectroscopy is used as a probe to demonstrate the interaction between cellulose and 1-butyl-3-methylimidazolium chloride. The fitting models of C 1s spectra for the ionic liquid, cellulose and cellulose containing solutions are developed. The measured binding energy of C² 1s component is used to indicate the ionic liquid-cellulose interaction. In the case of the cellulose containing solution, due to the weaker charge-transfer effect between hydrophilic groups of cellulose and the imidazolium cation, the C² atom is in a more electropositive environment and thus exhibits higher binding energy.