Detection of carbon residue on the surface of 3Y–ZrO2 powder and its effect on the rheology of the slip

The surface composition and rheology of two yttria doped zirconia powders (3Y-ZrO2) were investigated in aqueous suspensions using electron spectroscopy for chemical analysis (ESCA), infrared spectroscopy, potentiometric titration, electrophoretic mobility, and rheological measurements. Both physisorbed and chemisorbed carbon were detected on the surface of powders in different extent. The point of zero charge being different from the isoelectric point (iep) indicated the effect of carbon on the surface charge and likely the specific adsorption of cations inside the slipping plane. Infrared spectroscopy detected both physisorbed and chemisorbed carbon on the surface. Chemisorbed carbon also affected the rheology of the slips especially in acidic suspensions. Contact angle and surface energy measurements showed that powder with chemisorbed carbon has low surface energy and exhibited a hydrophobic surface.