Effects of acoustic waves generated on a positively polarized lead strontium zirconium titanate substrate upon catalytic activity of a deposited Ag thin film

A positively polarized lead strontium zirconium titanate (PSZT) substrate w as employed for the generation of thickness-extensional mode resonance osci llation (TERO), and the effects of TERO on the catalytic activity and the s urface properties of a 100-nm Ag film catalyst deposited on the substrate w ere investigated. The catalytic activity for ethanol oxidation increased 18 -fold with TERO at 3 W. In low energy photoelectron spectroscopy, a thresho ld energy for photoelectric emission from the Ag surface shifted linearly t o the lower energy side with increasing power of TERO, thus indicating a de crease in the work function of the Ag surface. On the basis of the behavior of lattice displacement measured by a laser Doppler method, a model for ch anges in catalytic activity and work function is proposed. (C) 2000 Elsevie r Science B.V. All rights: reserved.