Temperature-dependent vibration energy harvesting performance of polyimide/(Na,K)NbO₃ piezoelectric composites

Abstract

A composite structure of piezoelectric particles and soft polymer composite materials is one of the candidates that convert environmental vibration energy into electrical energy. Presently, expanding the usage of applications is needed in terms of the working environment at harsh temperatures. Polyimide is flexible and temperature–stable polymer. In this research, we report a synthesis of polyimide/(Na,K)NbO3 flexible composites. We constructed a setup, where vibration and heat are simultaneously applied to the PI/NKN composites. The frequency and temperature dependence of the output voltage were investigated at room temperature up to 200°C. Relative permittivity, piezoelectric constant, and output voltage of the PI/NKN showed temperature stability. Flexibility and glass transition temperature of a polymer matrix is important factors. PI/NKN composites are potential energy harvesting materials with flexibility and excellent high-temperature stability.

Investigation of the crystal-oriented behavior of rare earth substituted Sr2NaNb5O15 lead-free piezoelectric materials under a high magnetic field

“…Various lead-free piezoelectric materials, such as (K,Na)NbO 3 -based, (Bi,Na)TiO 3 -based, (Sr,Ca) 2 NaNb 5 O 15 (SCNN), and bismuth layer-structured ferroelectrics have been actively studied and reported to have certain advantages over PZT. [10][11][12][13][14][15][16][17][18][19][20] The c-axis crystal-oriented SCNN ceramics have good piezoelectric properties and outstanding high-power properties compared to hard-PZT, and have also demonstrated a superior performance as an ultrasonic motor using ceramics for highpower ultrasonic devices in our previous studies. 15,16,[21][22][23][24][25][26][27][28] However, there are challenges that must be addressed to achieve mass production.…”

Fabrication, Evaluation, and Multiscale Simulation of Piezoelectric Composites Reinforced Using Unidirectional Carbon Fibers for Flexible Motion Sensors

“…[ 1–4 ] A prominent piezoelectric material is Pb(Zr 1−x Ti x )O 3 . [ 5,6 ] However, lead‐free piezoelectric materials, such as (K 1−x Na x )NbO 3 (KNN), [ 7,8 ] BaTiO 3 , [ 9 ] and ZnO, [ 10,11 ] have become more commonplace due to increased environmental awareness. These materials are widely used in sensors and actuators due to their electromechanical conversion efficiency.…”