Importance of energy band theory and screening charge effect in piezo-electrocatalytical processes

The present study tries to shed more light on the controversial discussion around the ‘true’ mechanism behind piezo-electrocatalysis: energy band theory or screening charge effects. For this purpose, piezo-electrocatalysts made of three different materials with different energy band levels and piezoelectric properties, ZnO, BaTiO3 and BF-KBT-PT, were used to degrade Rhodamine B in aqueous solutions where combined ultrasound and mechanical agitation was used as the excitation method. The results suggest that both mechanisms may actually play an important role in the overall process, as the largest overall dye degradation was achieved with the piezo-electrocatalyst most likely to generate radicals via both piezo-electrocatalytic mechanisms.