Electrospraying systems and associated methods

Patent metadata

Field	Value
Publication number	US-2016107178-A1
Application number	US-201414892847-A
Country	US
Kind code	A1
Filing date	May 28, 2014
Priority date	May 28, 2013
Publication date	Apr 21, 2016
Grant date	—

Abstract

Electrospraying systems and associated methods are generally described.

First claim

What is claimed is:

1 . An emitter configured for use in an electrospraying device, comprising:
an array of protrusions extending from an emitter substrate, at least a portion of the protrusions in the array comprising a plurality of elongated nanostructures extending from external surfaces of the protrusions.

2 . The emitter of claim 1 , wherein at least a portion of the elongated nanostructures are nanotubes.

3 . The emitter of claim 2 , wherein at least a portion of the elongated nanostructures are carbon nanotubes and/or inorganic nanotubes.

4 . The emitter of any one of claims 1 - 3 , wherein at least a portion of the elongated nanostructures are nanofibers.

5 . The emitter of claim 4 , wherein at least a portion of the elongated nanostructures are carbon nanofibers and/or silicon carbide nanofibers.

6 . The emitter of any one of claims 1 - 5 , wherein the elongated nanostructures are substantially aligned.

7 . An emitter configured for use in an electrospraying device, comprising:
an array of protrusions extending from an emitter substrate, at least a portion of the protrusions in the array comprising a plurality of ordered nanostructures extending from external surfaces of the protrusions.

8 . An emitter configured for use in an electrospraying device, comprising:
an array of protrusions extending from an emitter substrate, at least a portion of the protrusions in the array comprising a plurality of nanostructures extending from an ordered intermediate material between the nanostructures and external surfaces of the protrusions.

9 . The emitter of claim 8 , wherein the ordered intermediate material comprises a catalyst used to form the nanostructures.

10 . The emitter of any one of claims 8 - 9 , wherein the ordered intermediate material comprises a metal.

11 . The emitter of claim 10 , wherein the metal comprises iron and/or gold.

12 . The emitter of any one of claims 8 - 11 , wherein the ordered intermediate material comprises a plurality of islands of the intermediate material.

13 . The emitter of claim 12 , wherein each of the islands of intermediate material have a nearest neighbor distance, and the standard deviation of the nearest neighbor distances are less than about 100% of the average of the nearest neighbor distances.

14 . The emitter of any one of claims 7 - 13 , wherein at least a portion of the nanostructures are nanotubes.

15 . The emitter of claim 14 , wherein at least a portion of the nanostructures are carbon nanotubes and/or inorganic nanotubes.

16 . The emitter of any one of claims 7 - 15 , wherein at least a portion of the nanostructures are nanofibers.

17 . The emitter of claim 16 , wherein at least a portion of the nanostructures are carbon nanofibers and/or silicon carbide nanofibers.

18 . The emitter of any one of claims 1 - 17 , wherein at least a portion of the emitter substrate and/or the emitters are formed of a semiconductor.

19 . The emitter of claim 18 , wherein the semiconductor comprises silicon.

20 . The emitter of any one of claims 1 - 19 , wherein at least a portion of the protrusions have maximum cross-sectional dimensions of at least about 1 micron.

21 . The emitter of any one of claims 1 - 20 , wherein the array comprises at least 10 protrusions having an aerial density of at least about 10 protrusions/cm 2 .

22 . The emitter of claim 21 , wherein the protrusions have an aerial density of between about 10 protrusions/cm 2 and about 100,000 protrusions/cm 2 .

23 . The emitter of any one of claims 1 - 22 , wherein the nanostructures are configured to transport fluid from bases of the protrusions to tips of the protrusions via capillary forces.

24 . The emitter of any one of claims 1 - 23 , wherein the protrusions do not contain internal fluid passageways.

25 . A system, comprising:
the emitter of any one of claims 1 - 24 ; and an electrode; wherein, when a voltage is applied across the emitter and electrode and the emitter is exposed to a fluid, droplets of the fluid are emitted from at least a portion of the protrusions of the emitter toward the electrode.

26 . The system of claim 25 , wherein the fluid is an ionic fluid.

27 . The system of any one of claims 25 - 26 , wherein the fluid comprises a plurality of particles suspended in the fluid.

28 . The system of claim 27 , wherein the plurality of particles suspended in the fluid forms a colloid.

29 . The system of claim 28 , wherein the plurality of particles makes up about 1 vol % or less of the colloid.

30 . The system of any one of claims 27 - 29 , wherein at least a portion of the particles are nanoparticles.

31 . The system of any one of claims 27 - 30 , wherein at least a portion of the particles comprise one or more metals.

32 . The system of claim 31 , wherein at least a portion of the particles comprise tungsten, cobalt, iron, nickel, molybdenum, copper, gold, silver, platinum, palladium, aluminum, zinc, tantalum, and/or titanium.

33 . The system of any one of claims 27 - 32 , wherein at least a portion of the particles comprise a ceramic materials, a carbon-containing material, a dielectric material, a semiconductor, a piezoelectric material, and/or a magnetic material.

34 . The system of claim 33 , wherein at least a portion of the particles comprise titanium dioxide.

35 . A method, comprising applying a voltage across the emitter of any one of claims 1 - 34 and an electrode such that fluid positioned between the emitter and the electrode is emitted from at least a portion of the protrusions of the emitter toward the electrode.

36 . The method of claim 35 , wherein the fluid is an ionic fluid.

37 . The method of any one of claims 35 - 36 , wherein the fluid comprises a plurality of particles suspended in the fluid.

38 . The method of claim 37 , wherein the plurality of particles suspended in the fluid forms a colloid.

39 . The method of claim 38 , wherein the plurality of particles makes up about 1 vol % or less of the colloid.

40 . The method of any one of claims 37 - 39 , wherein at least a portion of the particles are nanoparticles.

41 . The method of any one of claims 37 - 40 , wherein at least a portion of the particles comprise one or more metals.

42 . The method of claim 41 , wherein at least a portion of the particles comprise tungsten, cobalt, iron, nickel, molybdenum, copper, gold, silver, platinum, palladium, aluminum, zinc, tantalum, and/or titanium.

43 . The method of any one of claims 37 - 42 , wherein at least a portion of the particles comprise a ceramic material, a carbon-containing material, a dielectric material, a semiconductor, a piezoelectric material, and/or a magnetic material.

44 . The method of claim 43 , wherein at least a portion of the particles comprise titanium dioxide.

45 . The method of any one of claims 37 - 44 , wherein applying the voltage across the emitter and the electrode results in the expulsion of at least a portion of the particles within the fluid from the emitter toward th

Assignees

• Massachusetts Inst Technology

Inventors

• Velásquez-García Luis Fernando
• Hill Frances Ann
• James Philip

Classifications

• B05B5/057 Primary

  Arrangements for discharging liquids or other fluent material without using a gun or nozzle · CPC title

• C23C16/44

  characterised by the method of coating (C23C16/04 takes precedence) · CPC title

• C23C16/50

  using electric discharges {(generation and control of plasma in discharge tubes for surface treatment H01J37/32, H01J37/34)} · CPC title

• B05B5/0255

  spraying and depositing by electrostatic forces only · CPC title

• B05B5/0536

  Dimensional characteristics of electrodes, e.g. diameter or radius of curvature of a needle-like corona electrode · CPC title