Dispersion Stability of Inorganic Powders Harnessed to Mosaic Surface Ligands via Multifit Hansen Solubility Parameters

This study assessed the dispersion stability of industrial carbide/oxide powders that have mosaic surfaces comprised of multiple surface ligands. A large number (∼50) of probe liquids were used with an aim to effectively explain the data within the Hansen solubility parameter (HSP) framework. The proposed log-fit method, complemented by multi-HSP analysis featuring harmonic-mean-mixing HSPs, significantly improved the fit to experimental results for various mosaic-surface powders composed of complex surface ligands. X-ray photoelectron spectroscopy and thermal desorption spectroscopy analyses were employed synergistically to decipher the surface ligands of these mosaic-surface powders, which facilitated credible identification and quantification of the surface ligands. These results are in good agreement with the surface ligands and their coverage as determined by the multi-HSP analysis. Consequently, when it comes to characterizing powder surfaces, dispersion stability measurements paired with multi-HSP analysis are superior to conventional XPS and TDS analyses in terms of both topmost surface sensitivity and practicality.