Self-Powered Wireless Sensor Node Enabled by an Aerosol-Deposited PZT Flexible Energy Harvester

A piezoelectric aerosol-deposited (AD) Pb(Zr_x,Ti_1-x)O₃ (PZT) film prepared with single-step deposition and postannealing was successfully utilized to fabricate a high-performance flexible piezoelectric harvester via a fast, simple, and cost-effective method. The high temperature-annealed AD PZT thick film on a rigid sapphire substrate was transferred onto a flexible substrate by the inoranic-based laser lift-off process. The flexible PZT harvester can convert a maximum output voltage of 200 V and a current signal of 35 ΜA from biomechanical bending motions, which are comparable to those of a similar interdigitated electrode-type flexible single-crystal energy harvester. The high-output performance of the energy harvester originates from the large grain growth of the PZT ceramic film under the high temperature annealing process at 900°C, which leads to outstanding piezoelectric harvesting properties with robust endurance for up to around 115,000 bending cycles on a flexible substrate.