Radially dependent effective piezoelectric coefficient and enhanced piezoelectric potential due to geometrical stress confinement in ZnO nanowires/nanotubes

Abstract

A theoretical model for the radially dependent effective piezoelectric coefficient and corresponding piezoelectric potential in intrinsic ZnO nanowires (NWs)/nanotubes (NTs) is presented. Substrate-bound ZnO structures oriented along the c-axis with diameters of 100–5000 nm (NWs) and inner diameters of 100–900 nm (NTs; fixed outer diameter, 1000 nm) were examined using finite element method analysis. The piezoelectric potential depended nonlinearly on the NT/NW size, which we explain using the effective piezoelectric coefficient and peak piezoelectric potentials. We propose that this coefficient can be used to judge the degree of enhancement of the piezoelectric potential in ZnO NWs/NTs.

High‐Performance Piezoelectric Nanogenerators with Imprinted P(VDF‐TrFE)/BaTiO3 Nanocomposite Micropillars for Self‐Powered Flexible Sensors

“…Because the PDMS material was very soft in nature compared with P(VDF‐TrFE) or P(VDF‐TrFE)/BaTiO 3 nanocomposite material, so the embedded P(VDF‐TrFE)/BaTiO 3 pillars will not be constrained by the surrounding PDMS material, hence they are expected to deform more than the solid film. Besides, the geometrical strain confinement along the axial direction of the piezoelectric nanocomposite pillars can also lead to an enhancement of the piezoelectric potential . By reducing the diameter of the nanocomposite pillars or increase the height, the stress will be geometrically more confined in the axial direction, which leads to an enhanced piezoelectric output.…”

Effects of external surface charges on the enhanced piezoelectric potential of ZnO and AlN nanowires and nanotubes

“…) is related to the piezoelectric potential along the z-axis. 16 Next, we focus on the surface charges all around the surface of the NWs except for the fixed bottom of grounding potential, which can also induce an enhanced piezoelectric potential as the surface charge density increases. Fig.…”

Piezoelectric Nanogenerators Based on Helical Carbon Materials and Polyvinyledenedifluoride–Trifluoroethylene Hybrids with Enhanced Energy‐Harvesting Performance

“…Previous studies have shown that the geometry of piezoelectric materials also significantly affected the performance of the corresponding piezoelectric energy harvesters, besides their dielectric constant and piezoelectric coefficient . Structural design is one of the important parts of wearable flexible devices as well .…”

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“…Helical structures are one of the most common shapes in nature, from macroscopic plant vasculatures and tendrils to nanoscopic DNA. The helically structured nanobelt with a high ratio of inner‐to‐outer diameters should have a better performance than nanowires because of the stronger confinement effect . Hao et al theoretically predicted that the piezoelectric potential of the ZnO nanohelix was much higher than that of its nanowire based on FEM simulation .…”