Features of spectroscopy and formation process of silica sol-gel films doped with silver nanoparticles

Silver nanoparticles and clusters were produced within the conventional sol-gel process with tetraethylorthosilicate hydrolysis. The appearance of the reduced silver species was recorded by optical absorption spectroscopy as the plasmon resonances in the range of lambda < 370 nm, and the other absorption features (lambda < 370 nm) were prescribed to small silver clusters. The tuning of the preparation method can provide the participation of low-size pores in the sol-gel silica films like those in zeolites with regular cavities whose sizes are compatible with sizes of few-atomic clusters. (C) 2002 Elsevier Science B.V. All rights reserved.