Electrical behaviour of yttrium-doped potassium sodium niobate thin film for piezoelectric energy harvester applications

This study evaluates how the electrical characteristics of potassium sodium niobate, K0.5Na0.5NbO3 (KNN) thin film, are affected by yttrium doping. For the KNN thin films doped with yttrium, the secondary phase was not observed, which means that the films preserved the orthorhombic lattice. Yttrium doping affected the grain structure where microscopic doping concentration (0.5 mol%) was associated with higher homogeneity in the structure. In comparison, doping also led to the dielectric loss reducing to 0.02 at 0.5 mol% yttrium concentration. Additionally, the quality factor rose to 25.73, and the dielectric permittivity had an enhanced value of 508. KNN doped with 0.5 mol% yttrium was determined to be appropriate for applications concerning piezoelectric energy harvesting. Hence, the research highlights the enormous potential of yttrium-doped KNN as an alternative for the traditionally-used lead zirconate titanate (PZT) for harvesting piezoelectric energy. The results indicate that the thin film produced during the process was appropriate for use in high-frequency electronics.