Peculiar charging effects on titania in aqueous 1:1, 2:1, 1:2 and mixed electrolyte suspensions

► The charging and stability of titania suspensions can be conveniently controlled with 1:1, 2:1, 1:2 and mixed electrolytes. ► The concentration dependent differences between alkali and earth alkali cations result from solvation (hydration) effects. ► The concentration dependent influences of divalent anions may be related to their complexation behavior with surface sites. ► Combination of 1:1 and 2:1 or 1:2 (mixed) electrolytes leads partly to non-additive effects as a function of concentration. ► The difference between anatase and rutile depends on their manufacture plus properties and solids fraction of the suspension.