Stepwise Adsorption of Metal Alkoxides on Hydrolyzed Surfaces : A Surface Sol-Gel Process

Abstract
Ultrathin films of TiO2-based gel were prepared by repeating adsorption of titanium(IV) butoxide (Ti(O-nBu)4) and subsequent hydrolysis of the surface. Linear film growth was observed for at least 20 cycles, as monitored by quartz crystal microbalance (QCM). Similar thin films were prepared from aluminum(III) butoxide (Al(O-nBu)3), zirconium (IV) propoxide (Zr(O-nPr)4), niobium(V) butoxide (Nb(O-nBu)5), tetramethyl orthosilicate (Si(O-Me)4), and their combinations.