Piezo/triboelectric hybrid nanogenerators based on Ca-doped barium zirconate titanate embedded composite polymers for wearable electronics

Abstract Recently, hybrid nanogenerators (HNGs) based on the synergetic piezo/triboelectric effect have shown great promise for attaining high electrical output. In this work, microparticles (MPs) of calcium-doped barium zirconate titanate (Ca-BZT) are synthesized by a solid-state technique and subseqently dispersed into polydimethylsiloxane (PDMS) to prepare a composite film. This composite film is employed to develop an HNG device to efficiently harvest energy from various mechanical motions by individual piezoelectric or triboelectric effects, or a combined synergetic effect. The surface roughness, charge density, and dielectric permittivity of the composite films are significantly enhanced, resulting in an increase in output performance of the HNG device. The effect of Ca doping concentration on the ferroelectric characteristics of the BZT MPs and the output performance of the HNG device are systematically investigated. The BZT MPs with 2 mol% of Ca dopant optimize the high remnant polarization and piezoelectric coefficient of the Ca-BZT/PDMS composite. Moreover, the HNG device with the corresponding composite film also exhibits a maximum electrical output performance, with open-circuit voltage, short-circuit current, and power density values of 550 V, 34 μA, and 23.6 W/m2, respectively. Additionally, the mechanical stability and durability of the HNG device are investigated. To verify the practical applicability of the HNG, the generated output power is employed to demonstrate its ability to harvest biomedical energy and to power several light-emitting diodes as well as portable electronic devices.