Robust triboelectric nanogenerator based on rolling electrification

1. A generator comprising:

a first member; and

a second member comprising a plurality of substantially spherical members, the second member in contact with the first member to generate triboelectric charges, the second member being rollable against the first member to generate a flow of electrons between two electrodes.

2. The generator of claim 1 , wherein the first member defines a substantially planar configuration.

3. The generator of claim 1 , wherein the first member defines a substantially cylindrical configuration.

4. The generator of claim 1 , wherein the first member defines a substantially hollow cylindrical configuration.

5. The generator of claim 1 , wherein the first member includes a material selected from the group consisting of polyethylene terephthalate, poly(methyl methacrylate), polydimethylsiloxan, polytetrafluoroethylene, fluorinated ethylene propylene, poly(vinyl chloride), polyimide, metal and alloy.

6. The generator of claim 1 , wherein the first member includes a first layer and a second layer that are parallel to each other;

wherein at least one of the first and second layers is laterally movable with respect to the other; and

wherein the second member is disposed between the first and second layers.

7. The generator of claim 6 , wherein the first layer is deposited with a first pair of electrodes, and the second layer is deposited with a second pair of electrodes.

8. The generator of claim 7 , wherein the electrodes within each pair are electrically coupled to each other.

9. The generator of claim 7 , wherein the first and second layers each define a first edge and a second edge;

wherein the first pair of electrodes includes a first electrode adjacent to the first edge of the first layer and a second electrode adjacent to the second edge of the first layer;

wherein the second pair of electrodes includes a third electrode adjacent to the first edge of the second layer and a fourth electrode adjacent to the second edge of the second layer;

wherein the first electrode is electrically coupled to the fourth electrode; and

wherein the second electrode is electrically coupled to the third electrode.

10. The generator of claim 1 , wherein the electrodes include a material selected from the group consisting of metal, indium tin oxide and conductive polymer.

11. The generator of claim 1 , wherein the electrodes are adjacent to the first member.

12. The generator of claim 1 , wherein the second member exhibits a substantially cylindrical configuration.

13. The generator of claim 1 , wherein the second member includes a material selected from the group consisting of polyurethane, polyoxydiphenylene-pyromellitimide, polydimethylsiloxan, conductive polymer, metal and alloy.

14. The generator of claim 1 further comprising nanostructures on at least one of the first and second members.

15. The generator of claim 1 further comprising a supporting member to support the plurality of substantially spherical members.

16. The generator of claim 15 , wherein the supporting member includes a material selected from the group consisting of polyimide, polyethylene terephthalate, poly(methyl methacrylate), poly(4,4′-oxydiphenylene-pyromellitimide) and SiO 2 .

17. The generator of claim 1 , wherein the plurality of substantially spherical members are arranged in a fashion of parallel groups, each group forming a linear profile.

18. The generator of claim 1 , wherein the plurality of substantially spherical members form into a plurality of groups, each group being supported by a supporting member.

19. The generator of claim 18 , wherein each group containing a portion of the plurality of substantially spherical members exhibits a circular sector profile of a disk.

20. The generator of claim 1 further comprising a supporting member that supports the two electrodes.

21. The generator of claim 20 , wherein the supporting member includes a material selected from the group consisting of polyimide, polyethylene terephthalate, poly(methyl methacrylate), poly(4,4′-oxydiphenylene-pyromellitimide) and SiO 2 .

22. The generator of claim 1 , wherein the second member is in contact with and rollable against the two electrodes.

23. The generator of claim 1 , wherein the first member defines a substantially planar configuration and the second member defines a substantially cylindrical configuration.

24. The generator of claim 1 , wherein the first member defines a substantially hollow cylindrical configuration and the second member defines a substantially cylindrical configuration.

25. The generator of claim 1 , wherein the first member includes a fluorinated ethylene propylene film having a plurality of parallel, equidistant, identical metal gratings deposited thereon.

26. The generator of claim 1 , wherein the first member is rotatable about a fixed axis.

27. The generator of claim 1 further comprising a supporting member disposed within a hollow defined by the first member.

28. The generator of claim 1 , wherein the second member generates the flow of electrons between the two electrodes when the second member rolls from a first position aligned with one of the electrodes to a position aligned with the other electrode.

29. The generator of claim 1 , wherein the two electrodes are complementary grating electrodes.

30. The generator of claim 1 , wherein the two electrodes are complementary to form a disk profile.

31. The generator of claim 1 , wherein the two electrodes are complementary to form a hollow cylindrical configuration.

32. The generator of claim 1 , wherein the electrodes are interdigitated electrodes.

33. A generator comprising:

two electrodes; and

a member comprising a plurality of substantially spherical members, the member in contact with the two electrodes to generate triboelectric charges, the member being rollable against the electrodes to generate a flow of electrons between the two electrodes.

34. The generator of claim 33 further comprising a supporting member supporting the plurality of substantially spherical members.

35. The generator of claim 34 , wherein the supporting member includes a material selected from the group consisting of polyimide, polyethylene terephthalate, poly(methyl methacrylate), poly(4,4′-oxydiphenylene-pyromellitimide) and SiO 2 .

36. The generator of claim 33 further comprising a supporting member that supports the two electrodes.

37. The generator of claim 36 , wherein the supporting member includes a material selected from the group consisting of polyimide, polyethylene terephthalate, PMMA, poly(4,4′-oxydiphenylene-pyromellitimide) and SiO 2 .

38. The generator of claim 33 , wherein the member includes a material selected from the group consisting of polyethylene terephthalate, poly(methyl methacrylate), polydimethylsiloxan, polytetrafluoroethylene, fluorinated ethylene propylene, poly(vinyl chloride), polyimide, metal and alloy.

39. The generator of claim 33 , wherein the electrodes include includes a material selected from the group consisting of polyurethane, poly-oxydiphenylene-pyromellitimide, polydimethylsiloxan, conductive polymer, metal, alloy and indium tin oxide.

40. The generator of claim 33 , wherein the two electrodes comprise a pair of interdigitated electrodes; and

wherein the member comprises:

a first member adjacent to the electrodes; and

a second member in contact with the first member.

41. The generator of claim 33 , wherein the two electrodes comprise a pair of interdigitated electrodes;

wherein the member lies on top of the interdigitated electrodes, the member generating triboelectric charges when contacted by water; and

wherein the flow of electrons is generated between the interdigitated electrodes as water flows across the member from a position aligned with one electrode to a position aligned with the other electrode.