Piezoelectric Energy Harvester Based on LiNbO₃ Thin Films

This paper reports the results of the influence of the energy of laser pulses during laser ablation on the morphology and electro-physical properties of LiNbO₃ nanocrystalline films. It is found that increasing laser pulse energy from 180 to 220 mJ results in the concentration of charge carriers in LiNbO₃ films decreasing from 8.6 × 10¹⁵ to 1.0 × 10¹³ cm^-3, with the mobility of charge carriers increasing from 0.43 to 17.4 cm²/(V·s). In addition, experimental studies of sublayer material effects on the geometric parameters of carbon nanotubes (CNTs) are performed. It is found that the material of the lower electrode has a significant effect on the formation of CNTs. CNTs obtained at the same growth time on a sample with a Cr sublayer have a smaller diameter and a longer length compared to samples with a V sublayer. Based on the obtained results, the architecture of the energy nanogenerator is proposed. The current generated by the nanogenerator is 18 nA under mechanical stress of 600 nN. The obtained piezoelectric nanogenerator parameters are used to estimate the parameters of the hybrid-carbon-nanostructures-based piezoelectric energy converter. Obtained results are promising for the development of efficient energy converters for alternative energy devices based on lead-free ferroelectric films.