Enhanced Electricity Generation and Tunable Preservation in Porous Polymeric Materials via Coupled Piezoelectric and Dielectric Processes

Abstract

Biological systems and artificial devices convert omnipresent low‐frequency and weak mechanical stimulation into electricity for important functions. However, in‐depth understanding of the energy conversion, boosting, and preservation processes of the coupled piezo‐dielectric phenomenon in polymeric artificial materials is still lacking. In this study, combined experimental and simulation methods are employed to rationalize the process of energy conversion and preservation via a coupled piezo‐dielectric phenomena in composite polymeric films. Both the intensity of the transmembrane electric voltages and the kinetic aspects of the energy generation and preservation process are elucidated. The study indicates that composite films consisting of a conductive filler fraction below the percolation threshold, effectively convert low‐frequency mechanical stimulation to preserved electrical energy. Interestingly, film structure engineered into porous film has the ability to break the intertwined high‐voltage and exhibits a low‐preservation‐period relationship; it can simultaneously provide high electric field intensity, high induction velocity, and a long preservation period. The model is not only supported by the experiments but is also consistent with the electricity generation and preservation features of other reported piezo‐dielectric films. The systematic understanding can facilitate and inspire new device designs to better address the energy, environmental, and biomedical challenges faced by modern societies.

A healing promoting wound dressing with tailor-made antibacterial potency employing piezocatalytic processes in multi-functional nanocomposites

“…2b. 50 After a mechanical stimulus is applied to the film, the piezoelectric field ( V 1 ) is generated attributed to the reorientation of the H–C–C–F dipoles in the piezoelectrically active β phase during film deformation (I–II). Meanwhile, the conductive CB fillers are polarized under the effect of the piezoelectric field and produce an opposite electrical field denoted as V 2 , which would counter-balance V 1 , given a sufficient reorientation period and sufficient amount of movable electrons from the fillers (III).…”

Enzyme‐Mimetic Molecular Selective Catalysis via Single Zr Atom Catalysis in Chelated Cage Embedded in a Flexible Piezoelectrical Matrix

“…The crystalline peaks of MOP-NH 2 are absent in the composite film, indicating that MOP-NH 2 is highly dispersed in the composite film without detectable aggregation phase. Such microscopic morphology presents three advantages: (i) The MOP cage cavity can be used to capture guest molecules in a molecular selective manner, [16] (ii) The dense microscopic pores enhance piezoelectrical capacity in response to external mechanical stimuli, [17] and at the same time provide channels that allow the flow of guest molecular within the porous PVDF-HFP film, [18] and (iii) The large specific surface area can increase the catalytic active sites.…”

Understanding the Percolation Effect in Triboelectric Nanogenerator with Conductive Intermediate Layer

“…At the frequency of 1 kHz, the conductivity of the film increases from 1.49 to 13.89 × 10 −10 S/cm when the MXene loading transfers from 0% to 25%. It is worth noting that there is a sharp turning point in the dielectric permittivity and conductivity at the loading of 15%, revealing the existence of percolation [ 28 , 29 ]. At this turning point (percolation limit), the distance of the neighboring conductive fillers drops significantly resulting in a very thin insulator layer between the MXene flakes.…”