Performance of lead-free piezoelectric materials in cantilever-based energy harvesting devices

摘要

Energy harvesting is one of the emerging applications of piezoelectric materials. In order to replace conventional lead-based materials with lead-free materials, it is important to evaluate their performance for such applications. In the present study, finite element method-based simulation shows mean power density produced from (K_(0.475)Na_(0.475)Li_(0.05)) (Nb_(0.92)Ta_(0.05)Sb_(0.03)O_3 add with 0.4wt.% CeO_2 and 0.4wt.% MnO_2 (KNLNTS) bimorph is 96.64% of lead zirconate titanate (Pb [Zr_xTi_(1-x)] O_3) (PZT) ceramics. Load resistance (R), length of proof mass (L_m) and thickness of host layer (t_h) are optimized (using genetic algorithm) for maximum power density and tuning the operating frequency range which is near to natural frequency of the structure. The lead-free piezoelectric material KNLNTS has comparable results to that of PZT for piezoelectric energy harvester in the ambient frequency range of 90 Hz to 110 Hz. Results show that KNLNTS ceramics can be potentially used in energy harvesting devices.