High-performance low-velocity turbulent flow piezoelectric energy harvester using porous Ba0.85Ca0.15Zr0.1Ti0.9O3 (BCZT) ceramics

Piezoelectric energy harvesting of water flow offers a promising approach for directly powering Internet-of-Things (IoT) sensors used in water environment monitoring. However, its voltage and power outputs remain limited under practical flow conditions, especially in turbulent and low-velocity flows. To address this challenge, this work presents the first demonstration of a water flow energy harvester integrated with <i>d</i> ₃₃-mode and porosity-engineered lead-free Ba_0.85Ca_0.15Zr_0.1Ti_0.9O₃ (BCZT) piezoelectric ceramics. The performance of the harvester was experimentally evaluated in turbulent water flow at a low velocity of 0.1 m/s. During a capacitor charging test, the porous BCZT harvester achieved a 2.3-times increase in the saturated charging voltage (<i>V</i> _{<i>charge</i>} ) and a 5.1-fold increase in the charging power compared to the dense BCZT harvester. This work fills the knowledge gap related to piezoelectric harvesters in low-velocity turbulent flow, demonstrating the critical role of material design in water flow energy harvesting, and promoting the development of self-powered water monitoring technologies.