The present disclosure relates to a piezoelectric anode. a piezoelectric cathode, a unitized regenerative fuel cell comprising the piezoelectric anode and the piezoelectric cathode, and a method of fabricating thereof. The piezoelectric anode comprises metal oxide nanoparticles deposited over zero-dimensional (0D) material modified silica, a composite comprising carbon nanofibers and a zero-dimensional (0D) material, and an anode electro catalyst composition comprising alkali metal halide nanoparticles (NPs) and a polysaccharide. The piezoelectric cathode comprising metal-impregnated cellulose modified silica and a cathode electrocatalyst composition comprising calcium peroxide polymer(s).

A preparation method for a piezoelectric fiber is provided including a piezoelectric functional layer and an insulating layer coated on the piezoelectric functional layer. The piezoelectric functional layer includes a piezoelectric composite layer of a spiral winding structure, and the piezoelectric composite layer includes a first piezoelectric layer, a conductive layer and a second piezoelectric layer that are sequentially stacked. The preparation method includes taking one end of the piezoelectric composite layer as a winding axis, winding the piezoelectric composite layer in a direction perpendicular to the winding axis to form the piezoelectric functional layer, wherein turns of winding the piezoelectric composite layer are greater than 5, coating the piezoelectric functional layer with the insulating layer, and vacuum heating to consolidate, to prepare a preform rod.

A preparation method for a piezoelectric fiber is provided including a piezoelectric functional layer and an insulating layer coated on the piezoelectric functional layer. The piezoelectric functional layer includes a piezoelectric composite layer of a spiral winding structure, and the piezoelectric composite layer includes a first piezoelectric layer, a conductive layer and a second piezoelectric layer that are sequentially stacked. The preparation method includes taking one end of the piezoelectric composite layer as a winding axis, winding the piezoelectric composite layer in a direction perpendicular to the winding axis to form the piezoelectric functional layer, wherein turns of winding the piezoelectric composite layer are greater than 5, coating the piezoelectric functional layer with the insulating layer, and vacuum heating to consolidate, to prepare a preform rod.

The present invention provides a micro electromechanical system (MEMS), which includes: a base with a cavity, a vibration structure includes a structural layer, a piezoelectric composite layer and a flexible layer; the structural layer includes a structural slab, a structural fixing portion and a plurality of structural springs; the piezoelectric composite layer includes a piezoelectric film, a first electrode layer and a second electrode layer; the stress of the piezoelectric composite layer can be released through the elastic actions of the structural springs. In addition, the rigidity of the overall structure is ensured and will not be too low. Therefore, the sound pressure level of the MEMS piezoelectric loudspeaker is improved, and the THD is reduced to improve the performance of the MEMS piezoelectric loudspeaker.

The present invention provides a micro electromechanical system (MEMS), which includes: a base with a cavity, a vibration structure includes a structural layer, a piezoelectric composite layer and a flexible layer; the structural layer includes a structural slab, a structural fixing portion and a plurality of structural springs; the piezoelectric composite layer includes a piezoelectric film, a first electrode layer and a second electrode layer; the stress of the piezoelectric composite layer can be released through the elastic actions of the structural springs. In addition, the rigidity of the overall structure is ensured and will not be too low. Therefore, the sound pressure level of the MEMS piezoelectric loudspeaker is improved, and the THD is reduced to improve the performance of the MEMS piezoelectric loudspeaker.

Provided are a piezoelectric element for a speaker and a method of manufacturing the same. The piezoelectric element for a speaker includes a plurality of piezoelectric ceramic layers stacked on one another in a thickness direction, and a plurality of electrodes provided to be connected to middle portions of sides of the plurality of piezoelectric ceramic layers along external walls of the plurality of stacked piezoelectric ceramic layers, wherein middle portions of some sides from among a plurality of sides of each of the plurality of piezoelectric ceramic layers are etched, and wherein the plurality of piezoelectric ceramic layers are stacked on one another in the thickness direction not to overlap non-etched sides from among the plurality of sides.

A method for manufacturing a piezoelectric element for generating electricity upon flexing of the element including the steps spin-coating a first substrate layer onto a support substrate; depositing a first electrode film onto the first substrate layer; spin coating polyvinylidene fluoride (PVDF) containing solution on the first electrode film to result in a PVDF film; annealing the PVDF film; depositing a second electrode film onto the PVDF film; spin-coating a second substrate layer on top of the second electrode film; forming a hole through the first and second substrate layers; filling the hole with silver paste to contact to the first and second electrode layers; peeling a resulting substrate/electrode/PVDF/electrode/substrate device from the support substrate; and placing a drop of silver paste in the hole formed in the first substrate layer.

A method for manufacturing a piezoelectric element for generating electricity upon flexing of the element including the steps spin-coating a first substrate layer onto a support substrate; depositing a first electrode film onto the first substrate layer; spin coating polyvinylidene fluoride (PVDF) containing solution on the first electrode film to result in a PVDF film; annealing the PVDF film; depositing a second electrode film onto the PVDF film; spin-coating a second substrate layer on top of the second electrode film; forming a hole through the first and second substrate layers; filling the hole with silver paste to contact to the first and second electrode layers; peeling a resulting substrate/electrode/PVDF/electrode/substrate device from the support substrate; and placing a drop of silver paste in the hole formed in the first substrate layer.

A conductive piezoelectric multi-layer film having high transparency is achieved. A conductive piezoelectric multi-layer film is configured such that a first coating layer having a refractive index of 1.45 or greater and less than 1.60, a second coating layer having a refractive index of 1.60 or greater and less than 1.80, and a conductive layer having a refractive index of 1.80 or greater and 2.20 or less are stacked in this order on at least one surface of a piezoelectric film having a refractive index of 1.30 or greater and 1.50 or less.

A conductive piezoelectric multi-layer film having high transparency is achieved. A conductive piezoelectric multi-layer film is configured such that a first coating layer having a refractive index of 1.45 or greater and less than 1.60, a second coating layer having a refractive index of 1.60 or greater and less than 1.80, and a conductive layer having a refractive index of 1.80 or greater and 2.20 or less are stacked in this order on at least one surface of a piezoelectric film having a refractive index of 1.30 or greater and 1.50 or less.