Synergistic Effects of BaTiO₃/Multiwall Carbon Nanotube as Fillers on the Electrical Performance of Triboelectric Nanogenerator Based on Polydimethylsiloxane Composite Films

Abstract

Herein, polydimethylsiloxane (PDMS) composite films containing BaTiO3 particles with an average size of 70 and 500 nm are prepared and characterized, respectively. Then, triboelectric nanogenerators (TENG) based on the composite films are designed at different BaTiO3 sizes and mass ratios. In addition, multiwall carbon nanotubes (MWCNTs) are also used for uniform dispersion of BaTiO3 particles in composite films for the TENG device. With the synergistic effects of BaTiO3/MWCNT fillers, discrete conductive micronetworks surrounded by BaTiO3 particles form, and then, the effective filler–matrix interface effect in the three‐phase composite is enhanced, leading to superior triboelectric output performance, supported by much higher dielectric permittivity and COMSOL simulation. Moreover, the triboelectric output performance of TENG changes with different‐sized BaTiO3 particles. As to BT‐70‐MWCNT/PDMS composites, with the same mass ratio of BT, the peak output current is always higher than that of BT‐500‐MWCNT/PDMS. Furthermore, the optimum BT mass ratio of BT‐70‐MWCNT/PDMS composites is also higher than that of BT‐500. With BaTiO3 of size 70 nm, the maximum surface charge density is about 160 μC m−2 under an optimized mass ratio, whereas it is about 110 μC m−2 for BaTiO3 of size 500 nm.

Design and engineering of high‐performance triboelectric nanogenerator for ubiquitous unattended devices

“…Yu et al 259 extended the properties modification from the surface to the bulk of the triboelectric material by sequential infiltration synthesis. Moreover, filling high-dielectric-constant materials (eg, ceramic material, 72,148 ferroelectric materials, 88,149 piezoelectric material, 150,151 carbon-based materials, 152,153 MOFs, 154,155 and metal nanoparticles, 71,95 etc.) into the target triboelectric material could effectively improve its intrinsic dielectric properties and the TENG output.…”

“…The dielectric constant is one of the most critical parameters related to the triboelectric layers' surface charge density. 72,148 The transferred charge density under the SC condition can be expressed as 37 :…”

“…Typical high-dielectric-constant filler materials include ceramic material (BaTiO 3 ), 72,148 ferroelectric materials with strong spontaneous polarization, 88,149 piezoelectric material (NaNbO 3 , ZnSnO 3 ), 150,151 carbon-based materials (graphene, CNTs), 152,153 metal-organic frameworks (MOFs), 154,155 metal nanoparticles (Au, Ag NPs), 71,95 and so forth. For instance, Seung et al 88 reported that the poled ferroelectric poly(vinylidenefluoride-co-trifluoroethylene) could significantly improve the electron adsorption, and the high-dielectric-constant BaTiO 3 NPs possess strong charge-trapping capabilities.…”

“…The dielectric constant is one of the most critical parameters related to the triboelectric layers' surface charge density 72,148 . The transferred charge density under the SC condition can be expressed as 37 : Here, σ is the surface charge density of the dielectric layers; X(t) is the distance between two dielectric layers; ; d 1 , d 2 , and ε r 1 , ε r 2 are the thicknesses and dielectric constant of the two dielectric layers, respectively.…”

Nanostructured versus flat compact electrode for triboelectric nanogenerators at high humidity

“…In a flat surface, the amount of the nominal contact area is equal to the real contact area but in a rough or porous structure applying a mechanical force deform these surfaces forcing them to fill vacant spaces due to the elastic property, leading to an increased effective surface area 31 . So covering the substrate surface with the nanotube, nanoparticle, nanowire, and porous media can improve the performance of TENG due to an increased internal surface area as also suggested in 13,15,[32][33][34][35] . On the other hand, TENG charge vanishes in humid environments because of the formation of water film on the surface 19,36,37 .…”