Evgeni Eltzov, Abri Lavena De Cesarea, ‘Yuen Kei Adarina Low and Robert S. Marks
resonance frequency due to mass loading, has shown high sensitivity for chemicals and has potential application related to artificial noses ( 75 ). For example, piezoelectric substrate modified with SnO2 thinfilms was used for development hydrogen gas surface acoustic wave (SAW) sensors ( 76 ). In this study, enhancement of the sensor performance was proceed by creating bi-layer sensing film made from SnO2 and highly dispersed palladium nanoparticle layers. Also, SAW based sensors were used to monitor methanol, diesels and benzenes ( 77 ), nitrogen dioxides ( 78
for layer thickness was conducted in ThinFilm Companion (TFC) software (Semiconsoft).
Benchmarking the acidic corrosion of the iron surface
To establish a reference, corrosion of iron in acetic acid was monitored using QCM. Experiments were performed with 0.1M and 0.01M acetic acid at 25 °C, and the rates of iron dissolution were established. Fig. 1 . shows and example of the experimental results, the effect of 10 mM acetic acid on the iron surface at 25 °C. After an initial period (~8 min) linear increase of the frequency from zero to 2.3 kHz is