Commissariat a L'energie Atomique

Centre National De La Recherche Scientifique

Commissariat &#xc0; L'&#xc9;nergie Atomique Et Aux &#xc9;nergies Alternatives

Ecole Polytechnique

Commissariat a L'energie Atomique & Centre National De La Recherche

Emmanuel Balanzat

Charles Darnez

Jean-Paul Duraud

C Boiziau

Alain Le Moel

Travis Wade

Claude Bieth

Marie-Claude Clochard

Jean-Eric Wegrowe

Melilli Giuseppe

Eric Giglio

Alain LeMoel

Marcel Toulemonde

The invention relates to a process for fabricating a piezoelectric nanogenerator, to a piezoelectric nanogenerator obtained by this process and to a device including such a piezoelectric nanogenerator connected to a capacitor, said process comprising the following steps: a) providing a membrane () made of polarised &#x3b2;-PVDF or polarised P(VDF-TrFe) copolymer and therefore having piezoelectric properties, said membrane () moreover having two external major faces () that are separated by a membrane thickness (e); b) irradiating the entirety of the thickness of said membrane (), via at least one of its two external major faces (), with heavy ions having a fluence of between 103 ions/cm2 and 1010 ions/cm2, as a result of which a membrane () containing latent traces (TL) of the passage of the heavy ions through the entirety of its thickness is obtained; c) revealing the latent traces (TL) using a chemical process of length that is preset so as to preserve a defect zone (ZD) belonging to the latent trace, as a result of which a nanostructured membrane is obtained having nanopores including, around each nanopore, a defect zone (ZD); d) depositing a layer of an electrical conductor on one () of the two external major faces () of said membrane; e) electrodepositing an electrical conductor or semiconductor in the nanopores, the electrodeposition being stopped before the nanopores have been completely filled, as a result of which a nanostructured membrane is obtained having nanowires () partially filling the nanopores; and f) depositing a layer, of an electrical conductor, on the other () of the two external major faces () and which therefore does not make contact with the nanowires.

Process for fabricating a piezoelectric nanogenerator, piezoelectric nanogenerator obtained by this process and device including such a piezoelectric nanogenerator

The invention relates to the production of films having in their thickness at least two superimposed zones, including a semimetallic zone and an electrically insulating zone, by irradiating a polymer film by means of a high energy ion beam. It is possible by this process to produce semimetal (1)/insulant (2)/semimetal (3) structures by irradiating the polymer under vacuum by means of light ions or with a limited stopping power having an energy of at least 1 MeV/amu. It is also possible to obtain insulant (4)/semimetal (5)/insulant (6) structures by irradiating, in a confined atmosphere, the polymer by means of heavy ions or ions having a high energy loss with an energy of at least 1 MeV/amu. By irradiating only certain zones of the film, it is thus possible to form embedded or surface-positioned electrical connections.

Films having in their thickness at least two superimposed zones,

A first irradiation takes place with particles having an inadequate energy to traverse the membrane (5), followed by a second irradiation from the other face (26) of the membrane (5) using also non-issuing particles and whose trajectories come into contact with those of the other particles. Chemical etching produces pores (respectively 33, 34), whereof some issue into other pores produced during the other irradiation. As the finest pore determines the filtering properties, the selectivity of this membrane is very good.

Microporous membrane obtained by the irradiation of two faces and

Process for the production of asymmetrical microporous membranes by double irradiation. A membrane (5) is exposed to two irradiations, whereof one has an inadequate energy level to pass through the same, whereas the other passes through membrane (5). The irradiations produce molecular defects, which are attacked or etched in preferred manner by certain chemical agents. Thus, two networks of pores are obtained, one network being of large diameter and of a non-issuing nature (26), the other being smaller (27, 28, 29) and which issue on to the two surfaces (31, 32) of membrane (5). Application to filtration and sterilization.

Production of asymmetrical microporous membranes by double irradiation

Growing community of inventors

Caen, France

Emmanuel Balanzat