Passivated nanoparticles, method of fabrication thereof, and devices incorporating nanoparticles

• US 20070248826A1
• Filed: 06/27/2007
• Published: 10/25/2007
• Est. Priority Date: 09/05/2001
• Status: Active Grant

• Current Assignee: Rensselaer Polytechnic Institute
• Original Assignee: Rensselaer Polytechnic Institute
• Inventors: Dutta, Partha
• Granted Patent: US 7,834,468 B2
• Time in Patent Office: Days
• US Class Current: 428/403
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C01B 19/007 Tellurides or selenides of metals C01B19/002 takes precedence
• CPC Class Codes: C01G 21/21 Sulfides
• CPC Class Codes: C01P 2004/52 highly monodisperse size distribution
• CPC Class Codes: C01P 2004/64 Nanometer sized, i.e. from 1-100 nanometer
• CPC Class Codes: C01P 2006/40 Electric properties
• CPC Class Codes: C09D 11/52 Electrically conductive inks
• CPC Class Codes: C09D 5/028 Pigments; Filters
• CPC Class Codes: C09D 5/24 Electrically-conducting paints conductive materials H01B1/00
• CPC Class Codes: C09K 11/025 non-luminescent particle coatings or suspension media
• CPC Class Codes: C30B 29/40 AIIIBV compounds wherein A is B, Al, Ga, In or Tl and B is N, P, As, Sb or Bi
• CPC Class Codes: C30B 29/48 AIIBVI compounds wherein A is Zn, Cd or Hg, and B is S, Se or Te
• CPC Class Codes: C30B 29/605 Products containing multiple oriented crystallites, e.g. columnar crystallites
• CPC Class Codes: C30B 7/00 Single-crystal growth from solutions using solvents which are liquid at normal temperature, e.g. aqueous solutions from molten solvents C30B9/00; by normal or gradient freezing C30B11/00; under a protective fluid C30B27/00
• CPC Class Codes: C30B 7/14 the crystallising materials being formed by chemical reactions in the solution
• CPC Class Codes: H01L 21/02521 Materials
• CPC Class Codes: H01L 21/02568 Chalcogenide semiconducting materials not being oxides, e.g. ternary compounds
• CPC Class Codes: H01L 21/02601 Nanoparticles fullerenes H10K85/211
• CPC Class Codes: H01L 21/02628 using solutions
• CPC Class Codes: H01L 21/02664 Aftertreatments planarisation in general H01L21/304
• CPC Class Codes: H10K 50/11 : characterised by the electroluminescent [EL] layers
• CPC Class Codes: Y10S 977/778 : within specified host or matrix material, e.g. nanocomposite films
• CPC Class Codes: Y10S 977/786 : Fluidic host/matrix containing nanomaterials
• CPC Class Codes: Y10S 977/813 : Of specified inorganic semiconductor composition, e.g. periodic table group IV-VI compositions
• CPC Class Codes: Y10S 977/835 : Chemical or nuclear reactivity/stability of composition or compound forming nanomaterial
• CPC Class Codes: Y10S 977/847 : Surface modifications, e.g. functionalization, coating
• CPC Class Codes: Y10S 977/856 : including etching/cutting
• CPC Class Codes: Y10S 977/888 : Shaping or removal of materials, e.g. etching
• CPC Class Codes: Y10T 428/2991 : Coated

Abstract

A plurality of semiconductor nanoparticles having an elementally passivated surface are provided. These nanoparticles are capable of being suspended in water without substantial agglomeration and substantial precipitation on container surfaces for at least 30 days. The method of making the semiconductor nanoparticles includes reacting at least a first reactant and a second reactant in a solution to form the semiconductor nanoparticles in the solution. A first reactant provides a passivating element which binds to dangling bonds on a surface of the nanoparticles to passivate the surface of the nanoparticles. The nanoparticle size can be tuned by etching the nanoparticles located in the solution to a desired size.

Claims

1. A plurality of semiconductor nanoparticles having an elementally passivated surface.

2. The nanoparticles of claim 1, wherein the passivated surface comprises passivated dangling bonds.

3. The nanoparticles of claim 2, wherein the passivated surface comprises an inorganic passivating element bound to the dangling bonds.

4. The nanoparticles of claim 3, wherein:

the nanoparticles comprise a II-VI, IV-VI, or a III-V semiconductor material; and

the passivating element is selected from a group consisting of H, S, Se and Te.

5. The nanoparticles of claim 4, wherein the passivating element is sulfur.

6. The nanoparticles of claim 5, wherein the nanoparticles are selected from a group consisting of CdS, PbS, ZnS and compounds thereof.

7. The nanoparticles of claim 6, wherein the nanoparticles comprise PbS nanoparticles having an average size of 2 to 100 nm.

8. The nanoparticles of claim 4, wherein:

the nanoparticles are selected from a group consisting of CdSe, ZnSe, PbSe and compounds thereof; and

the passivating element comprises Se.

9. The nanoparticles of claim 5, wherein the nanoparticles comprise a III-V semiconductor material.

10. The nanoparticles of claim 3, wherein the nanoparticles are capable of being suspended in water without substantial agglomeration and substantial precipitation on container surfaces for at least 30 days.

11. The nanoparticles of claim 10, wherein the nanoparticles are suspended in water without substantial agglomeration and substantial precipitation on container surfaces.

12. The nanoparticles of claim 1, wherein the nanoparticles have an average size between about 2 nm and about 100 nm with a size standard deviation of less than 60 percent of the average nanoparticle size measured by photon correlated spectroscopy (PCS) method.

13. The nanoparticles of claim 1, wherein:

the nanoparticles are suspended in a solution, suspension or mixture;

or

the nanoparticles are located on a solid substrate or in a solid matrix.

14. An article of manufacture comprising the nanoparticles of claim 1, selected from the group consisting of:

(a) polishing slurry comprising a polishing slurry fluid and the nanoparticles of claim 1 in the slurry fluid;

(b) a device containing a hardness or wear resistant coating, wherein the coating comprises the nanoparticles of claim 1, located on at least a portion of the device;

(c) an ultra low porosity material having a porosity below 10 volume percent comprising a solid matrix and the nanoparticles of claim 1 incorporated into the matrix;

(d) a filter comprising compressed nanoparticles of claim 1;

(e) a paint comprising a liquid base and the nanoparticles of claim 1;

(f) an article of clothing or footwear containing a moisture barrier, wherein the moisture barrier comprises a layer of nanoparticles of claim 1, located on at least one surface of the article;

(g) an environmental sensor comprising a radiation source and a matrix material containing the nanoparticles of claim 1;

(h) a light emitting device comprising light emitting nanoparticles of claim 1;

(i) an organic light emitting diode comprising an organic light emitting material in a matrix of nanoparticles of claim 1, a first electrode, and a second electrode;

(j) a lamp, comprising a shell, a source of radiation located in the shell, and a layer of nanoparticles of claim 1 located on at least one surface of the shell, wherein the nanoparticles absorb the radiation emitted by the radiation source and emit visible light;

(k) a magnetic data storage device comprising a magnetic field source, a data storage medium comprising the nanoparticles of claim 1;

and a photodetector which detects radiation emitted from the nanoparticles in response to the application of a magnetic field by the magnetic field source;

(l) a magnetic storage medium comprising a magnetic material and the nanoparticles of claim 1;

(m) an optical storage medium comprising a substrate, and the nanoparticles of claim 1 located in predetermined areas of the substrate, such that first areas of the substrate contain the nanoparticles while the second areas of the substrate do not contain the nanoparticles;

(n) an optical system, comprising at least one microcantilever, and light emitting nanoparticles comprising the nanoparticles of claim 1 located on a tip of the at least one microcantilever;

(o) an optical switch, comprising light emitting nanoparticles comprising the nanoparticles of claim 1, and a source of magnetic field which is adapted to extinguish radiation emitted by the nanoparticles when it provides a magnetic field adjacent to the nanoparticles;

(p) an ink comprising a liquid ink and the nanoparticles of claim 1;

and

(q) a cleaning composition comprising a cleaning fluid containing the nanoparticles of claim 1.

15. The article of claim 14, wherein:

the device (b) comprises at least one of a tool, a drill bit, a turbine blade, a gear and a cutting apparatus;

the liquid base of the paint (e) evaporates after being applied to a surface, such that the nanoparticles of claim 1 provide a color to a surface;

the moisture barrier of the apparel or footwear (f) generates heat when exposed to sunlight or traps heat emitted by a body;

the layer of nanoparticles in the lamp (j) contains nanoparticles which emit different color light, such that the combined light output of the nanoparticles appears as white light to a human observer; and

the nanoparticles in the magnetic storage medium (l) comprise barrier layers located in the magnetic material such that the barrier layers form domain walls in the magnetic material or the medium (l) further comprises a substrate containing the nanoparticles doped with atoms of the magnetic material, such that each nanoparticle is adapted to store one bit of data.

16-43. -43. (canceled)

44. An article, comprising one of:

(a) a polishing slurry comprising a polishing slurry fluid containing semiconductor nanoparticles;

(b) a device comprising a semiconductor nanoparticle hardness or wear resistant coating located on at least a portion of the device;

(c) an ultra low porosity material having a porosity below 10 volume percent comprising a solid matrix and semiconductor nanoparticles incorporated into the matrix;

(d) a filter comprising semiconductor nanoparticles;

(e) a paint comprising a liquid base and semiconductor nanoparticles;

(f) an article of apparel or footwear comprising a semiconductor nanoparticle moisture barrier layer located on at least one surface of the article;

(g) an edifice comprising a semiconductor nanoparticle moisture barrier layer located on at least one surface of the edifice;

(h) an environmental sensor comprising a radiation source and a matrix material containing semiconductor nanoparticles;

(i) an organic light emitting diode comprising an organic light emitting material in a matrix of semiconductor nanoparticles, a first electrode, and a second electrode;

(j) a lamp, comprising a shell a source of radiation located in the shell, and a layer of semiconductor nanoparticles located on at least one surface of the shell which absorb the radiation emitted by the radiation source and emit visible light;

(k) a magnetic data storage device comprising a magnetic field source, a data storage medium comprising semiconductor nanoparticles, and a photodetector which detects radiation emitted from the nanoparticles in response to the application of a magnetic field by the magnetic field source;

(l) a magnetic storage medium comprising a magnetic material and semiconductor nanoparticles;

(m) an optical storage medium comprising a substrate, and semiconductor nanoparticles located in predetermined areas of the substrate, such that first areas of the substrate contain the nanoparticles, while second areas of the substrate do not contain the nanoparticles;

(n) an optical system, comprising at least one microcantilever, and light emitting semiconductor nanoparticles located on a tip of the at least one microcantilever;

(o) an optical switch, comprising light emitting semiconductor nanoparticles, and a source of magnetic field which is adapted to extinguish radiation emitted by the nanoparticles when it provides a magnetic field adjacent to the nanoparticles;

(p) an ink composition comprising a liquid ink and semiconductor nanoparticles; and

(q) a cleaning composition comprising a cleaning fluid containing semiconductor nanoparticles.

45. The article of claim 44, wherein:

the device (b) comprises at least one of a tool, a drill bit, a turbine blade, a gear and a cutting apparatus;

the liquid base of the paint (e) evaporates after being applied to a surface, such that the nanoparticles provide a color to the surface;

the moisture barrier of the apparel or footwear (f) generates heat when exposed to sunlight or traps heat emitted by a body;

the layer of nanoparticles in the lamp (j) contains nanoparticles which emit different color light, such that the combined light output of the nanoparticles appears as white light to a human observer; and

the nanoparticles in the magnetic storage medium (l) comprise barrier layers located in the magnetic material such that the barrier layers form domain walls in the magnetic material or the medium (l) further comprises a substrate containing the nanoparticles doped with atoms of the magnetic material, such that each nanoparticle is adapted to store one bit of data.

46. The article of claim 44, wherein dangling bonds on the semiconductor nanoparticle surface are passivated with an inorganic passivating element bound to the dangling bonds.