Experimental study of TiO2 nanoparticle adhesion to silica and Fe(III) oxide-coated silica surfaces

► pH strongly affects TiO2 nanoparticle adhesion to both Fe-coated and uncoated silica. ► Below pHzpc, TiO2 adhesion increases with increasing pH. ► Above pHzpc, TiO2 adhesion is independent of pH. ► TiO2 adhesion onto Fe-coated silica is similar to that observed onto uncoated silica. ► Our data suggest preferential adhesion of larger particles or agglomerates.