Abstract: Surface modification of atomic layer deposited (ALD) films with organic species is an ideal way to tailor the surface properties. Here we demonstrate the vapor-phase grafting of various functional silanes on ALD metal oxides. We investigate the grafting of six different silanes with amine, thiol, nitrile and ester functionalities at 100 ℃, 150 ℃ and 200 ℃ temperatures on flat surfaces. It is shown that the density of reacted silanes and surface hydrophobicity can be tuned by using different bifunctional silane agents, on different metal oxides, at different temperatures. Then we extend the study onto porous substrates by coating porous silica with thin ALD metal oxide films followed by grafting with monolayer functional silanes. Currently, we are investigating metal ion adsorption performance of these surfaces.