Publication

NMSL Lab

Publication

0.8BNT–0.2BKT Ferroelectric-based Multimode Energy Harvester for Self-powered Body Motion Sensors
Author
Nirmal Prashanth Maria Joseph Raj, Gaurav Khandelwal, Sang-Jae Kim
Journal
Nano Energy
Page
105848
Year
2021

Abstract

Exploring the various modes of forces such as tensile, bending along with regular compressive force stimulation is required to achieve superior applications from piezoelectric nanogenerators (PENG). The synthesized 1-x(Bi0.5Na0.5TiO3)-x(Bi0.5K0.5TiO3) (BNKT) structural analysis revealed the formation of a morphotropic phase boundary (MPB) at x = 0.2. The MPB 0.8BNT–0.2BKT system exhibited a dielectric constant of 1338 at 1 kHz, a remanent polarization (Pr) of 37.14 μC/cm2 with a coercive field (Ec) of 28.8 kV/cm at 1 Hz, and a piezoelectric coefficient (d33) of 110 pC/N. Composite films based on BNKT82 were then used to prepare stretchable, planar, and compressive PENGs. The stretchable PENG (SPENG) generated 8.1 V and 80 nA. The planar PENG (PPENG) in bending mode yielded 12.5 V and 110 nA, while the same device in compressive mode delivered 22.5 V and 210 nA with a power density of 13.81 mW/m2 at 90 MΩ. The PENGs analyzed under poled, unpoled, displacement, and acceleration effects systematically; also inspected stability, capacitor charging tests. The PENGs are demonstrated as self-powered human body sensors under the multimode of forces generated by the human body's movement.