Large‐Area and Flexible Lead‐Free Nanocomposite Generator Using Alkaline Niobate Particles and Metal Nanorod Filler

Abstract

The lead‐free nanocomposite generator device for high‐output energy harvesting using piezoelectric alkaline niobate‐based particles (KNLN) and copper (Cu) nanorods filler is reported. To produce the piezoelectric nanocomposite (p‐NC), lead‐free KNLN particles synthesized using a solid‐state method and the Cu nanorods are distributed in a polydimethylsiloxane (PDMS) matrix. The lead‐free flexible nanocomposite generator (NCG) made by a simple spin‐casting method successfully converts mechanical energy to electricity up to 12 V and 1.2 μA. These are higher than previously reported outputs from other lead‐free and composite‐based nanogenerators. The harvested energy is utilized to directly turn on white light emitting diodes (LEDs) without external circuits and to operate a complex circuital liquid crystal display (LCD). A large‐area NCG device (30 cm × 30 cm) is also fabricated using the bar‐coating method to obtain maximum output up to 140 V and 8 μA (≈0.5 mW). This NCG technology has substantial advantages as a simple, cost‐effective, scalable, and high‐throughput approach for practical flexible electronics, bio‐eco‐compatible self‐powered systems, and body sensor networks (BSN).