Triboelectric nanogenerators based on chemically treated cellulose

Patent metadata

Field	Value
Publication number	US-10277147-B2
Application number	US-201615178285-A
Country	US
Kind code	B2
Filing date	Jun 9, 2016
Priority date	Jun 9, 2016
Publication date	Apr 30, 2019
Grant date	Apr 30, 2019

Abstract

Triboelectric nanogenerators that operate in a vertical contact separation mode and methods for fabricating the triboelectric generators are provided. Also provided are methods for using the triboelectric nanogenerators to harvest mechanical energy and convert it into electric energy. In the TENGs, one or both of the triboelectrically active layers comprises a cellulose that has been chemically treated to alter its electron affinity.

First claim

What is claimed is:

1. A triboelectric nanogenerator comprising:
a first electrode comprising a positive active layer comprising cellulose, the positive active layer having a front surface with a positive surface charge and an oppositely facing back surface;
a second electrode comprising a negative active layer comprising cellulose, the negative active layer having a front surface with a negative surface charge and an oppositely facing back surface;
a third electrode comprising a third active layer that is either a positive active layer comprising cellulose or a negative active layer comprising cellulose, the third active layer having a front surface with a positive surface charge if it is a positive active layer, or a negative surface charge if it is a negative active layer, and an oppositely facing back surface; wherein the positive active layer, the negative active layer, and the third active layer are dielectric layers;
a first electrically conducting contact layer on the back surface of one of the positive active layer, the negative active layer, or the third active layer;
a second electrically conducting contact layer on the back surface of another of the positive active layer, the negative active layer, or the third active layer; and
an external load connected across the first and second electrically conducting contact layers, such that the first and second electrically conducting contact layers are in electrical communication through the external load,
wherein the front surface of each of the positive active layer, the negative active layer, and the third active layer is disposed opposite and facing the front surface of at least one other of the positive active layer, the negative active layer, and the third active layer, and
further wherein the positive active layer, the negative active layer, and the third active layer are configured to be moved with respect to one another in a periodic manner that generates a periodically varying electric potential difference between the first electrically conducting contact layer and the second electrically conducting contact layer, and further wherein the cellulose of at least one of the positive active layer, the negative active layer, and the third active layer comprises a chemical functional group that provides the negative and positive active layers with different electron affinities.

2. The nanogenerator of claim 1 , wherein the cellulose of at least one of the positive active layer, the negative active layer, and the third active layer comprises a chemical functional group independently selected from amine groups, methyl groups, ethyl groups, sulfate groups, acetate groups, nitro groups, fluoro groups, chloro groups, or a combination thereof.

3. The nanogenerator of claim 1 , wherein the cellulose of the positive active layer comprises a first chemical functional group that provides the cellulose with a lower electron affinity than unfunctionalized cellulose, and the cellulose of the negative active layer comprises a second chemical functional group that provides the cellulose with a higher electron affinity than unfunctionalized cellulose.

4. The nanogenerator of claim 3 , wherein the first chemical functional group is selected from amine groups, methyl groups, ethyl groups, sulfate groups, acetate groups, or a combination thereof, and the second chemical functional group is selected from nitro groups, fluoro groups, chloro groups, or a combination thereof.

5. The nanogenerator of claim 4 , wherein the first chemical functional group is an amine group and the second chemical functional group is a fluoro group.

6. The nanogenerator of claim 1 , wherein at least one of the positive active layer, the negative active layer, and the third active layer comprises a lignocellulosic material that comprises the cellulose and also comprises hemicelluloses and lignin.

7. The nanogenerator of claim 6 , wherein the cellulosic material comprises a wood fiberboard.

8. The nanogenerator of claim 1 , wherein at least one of the positive active layer, the negative active layer, and the third active layer is an optically transparent layer comprising cellulose in the form of cellulose nanofibrils.

9. The nanogenerator of claim 1 , wherein the chemical functional groups are present from the front surface of the positive active layer, the negative active layer, or the third active layer through at least 1% of the thickness of the positive active layer, the negative active layer, or the third active layer.

10. The nanogenerator of claim 1 , wherein the chemical functional groups are present throughout the thickness of the positive active layer, the negative active layer, or the third active layer.

11. A triboelectric nanogenerator comprising:
a positive active layer comprising cellulose, the positive active layer having a front surface and an oppositely facing back surface;
a negative active layer comprising cellulose, the negative active layer having a front surface and an oppositely facing back surface, wherein the positive active layer and the negative active layer are dielectric layers;
a first electrically conducting contact layer on the back surface of the positive active layer;
a second electrically conducting contact layer on the back surface of the negative active layer; and
an external load connected across the first and second electrically conducting contact layers, such that the first and second electrically conducting contact layers are in electrical communication through the external load,
wherein the front surface of the positive active layer is disposed opposite and facing the front surface of the negative active layer, and the positive and negative active layers are configured to be moved with respect to one another in a periodic manner that generates a periodically varying electric potential difference between the first electrically conducting contact layer and the second electrically conducting contact layer, and further wherein the cellulose of at least one of the positive and negative active layers comprises a chemical functional group that provides the negative and positive active layers with different electron affinities.

12. The nanogenerator of claim 11 , wherein the cellulose of at least one of the positive active layer and the negative active layer comprises a chemical functional group independently selected from amine groups, methyl groups, ethyl groups, sulfate groups, acetate groups, nitro groups, fluoro groups, chloro groups, or a combination thereof.

13. The nanogenerator of claim 11 , wherein the cellulose of the positive active layer comprises a first chemical functional group that provides the cellulose with a lower electron affinity than unfunctionalized cellulose, and the cellulose of the negative active layer comprises a second chemical functional group that provides the cellulose with a higher electron affinity than unfunctionalized cellulose.

14. The nanogenerator of claim 13 , wherein the first chemical functional group is selected from amine groups, methyl groups, ethyl groups, sulfate groups, acetate groups, or a combination thereof, and the second chemical functional group is selected from nitro groups, fluoro groups, chloro groups, or a combination thereof.

15. The nanogenerator of claim 14 , wherein the first chemical functional group is an amine group and the second chemical functional group is a fluoro group.

16. The nanogenerator of claim 11 , wherein at least one of the positive active layer and the negative active layer comprises a lignocellulosic material that comprises the cellulose and also comprises hemicelluloses

Assignees

• Wisconsin Alumni Res Found
• Us Agriculture

Inventors

• Wang Xudong
• Cai Zhiyong
• Yao Chunhua
• Hernandez Alberto
• Yu Yanhao

Classifications

• H02N1/04 Primary

  Friction generators · CPC title

• B29C65/00

  Joining {or sealing} of preformed parts {, e.g. welding of plastics materials}; Apparatus therefor {(general aspects of processes or apparatus for joining preformed parts B29C66/00; using porous material formed by internal pressure generated therein for joining preformed parts B29C44/1228, B29C44/326)} · CPC title

• B29K2001/08

  Cellulose derivatives · CPC title

• C23C16/30

  Deposition of compounds, mixtures or solid solutions, e.g. borides, carbides, nitrides · CPC title

• B29C43/02

  of articles of definite length, i.e. discrete articles {(B29C35/0227 takes precedence)} · CPC title