Multiferroic BiFeO₃-based hydrophobic polymer composites for polarization rationalization-induced piezo-tribo hybrid energy harvesting and versatile self-powered mechanosensing

Abstract

In recent times, BiFeO3 (BFO) has become one of the best multifunctional materials due to its several real life applications including multiferroicity, piezoelectricity, magnetism, photovoltaics, spintronics, gas sensing and photocatalysis....

Two-Dimensional Metal-Organic Framework Incorporated Highly Polar PVDF for Dielectric Energy Storage and Mechanical Energy Harvesting

“…Apart from piezoelectric energy harvesting, PVDF-based composite films can be applied for triboelectric energy harvesting too. Triboelectric energy harvesting mainly relies on the mechanism of contact electrification and electrostatic induction [ 63 ]. Therefore, the surface roughness, the difference between the positions of two used triboelectric layers (for contact-separation modes) in the triboelectric series, and many other factors determine the performance of triboelectric nanogenerators.…”

“…Therefore, the surface roughness, the difference between the positions of two used triboelectric layers (for contact-separation modes) in the triboelectric series, and many other factors determine the performance of triboelectric nanogenerators. All these mentioned factors directly or indirectly affect the surface triboelectric charge density ( σ ), which directly determines the output V OC of triboelectric nanogenerators by following Equation (8) as depicted below [ 63 , 64 ]. …”

“…Here, ε 0 and x ( t ) represent the free space permittivity and distance between two triboelectric layers (one dielectric layer and another metal electrode in the present case of device design), respectively. If the distance between two layers, the relative permittivity of the dielectric layer, the work function of the upper metal electrode, and the work function of lower dielectric material be represented by d , ε r , Φ M , and Φ D , respectively, the surface triboelectric charge density ( σ ) can be expressed by the Equation (9) as given below [ 63 , 64 ]. …”

“…Thus, this result clearly proves the superiority of NPVDFH devices for real-life energy harvesting applications. The improved performance of the fabricated HNGs compared to that of the corresponding PENGs is directly associated with the combined effect of piezoelectricity and contact electrification [ 59 , 63 ], as described below.…”

Piezo-Enhanced Photocatalytic Activity of the Electrospun Fibrous Magnetic PVDF/BiFeO3 Membrane

“…Among them, polyvinylidene fluoride (PVDF) is a great choice as a matrix for BFO since it is possible to obtain a piezo-photocatalyst similar to those previously reported [ 28 , 29 ]. The creation of composite polymers based on BFO for various applications was reported earlier [ 30 , 31 , 32 , 33 ]. However, to our knowledge, there have been no studies related to the synthesis of composite fiber membranes based on PVDF and BFO, and no investigations have been conducted to examine their photo-, piezo-, and piezo-photocatalytic properties.…”