Application of BiFeO₃ Thin Films for Vibration Energy Harvesting

Abstract

Recently, vibration energy harvesting is receiving a considerable amount of interest. For the piezoelectric vibration energy harvester, the piezoelectrics with low dielectric permittivity and large piezoelectric coefficient are suitable to obtain high conversion efficiency. In this study, BiFeO₃ is focused as one of the promising materials for piezoelectric energy harvester, because BiFeO3 has relatively low dielectric permittivity (~50). The piezoelectric properties of the BiFeO₃ films with different crystal system and orientation were characterized. It was found that the (100) BiFeO₃ films with rhombohedral structure have the largest effective transverse piezoelectric coefficient (e_31,f) of -3.5C/m².