Process for coating with single source precursors

• US 5,425,966 A
• Filed: 10/27/1994
• Issued: 06/20/1995
• Est. Priority Date: 10/27/1994
• Status: Expired due to Fees

• Current Assignee: Wayne State University
• Original Assignee: Wayne State University
• Inventors: Lewkebandara, T. Suren, Winter, Charles H.
• Primary Examiner(s): PIANALTO, BERNARD D
• Application Number:
  US08/329,841
• Time in Patent Office: 236 Days
• Field of Search: 427/294, 427/248.1, 427/255.1
• US Class Current: 427/255.36
• CPC Class Codes: C23C 16/305 Sulfides, selenides, or tellurides
• CPC Class Codes: H01M 4/04 Processes of manufacture in general
• CPC Class Codes: H01M 4/0404 by coating on electrode collectors
• CPC Class Codes: H01M 4/0428 Chemical vapour deposition
• CPC Class Codes: H01M 4/581 Chalcogenides or intercalation compounds thereof
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

Reaction products of metal halides with organic chalcogenides and dichalcogenides provide single source precursors for metal dichalcogenide coatings. The single source precursors are sublimed at reduced pressure and allowed to contact a substrate maintained at an elevated temperature. The resulting dichalcogenide coatings are smooth, and adherent, and may be utilized in numerous applications, for example, as cathodes for lithium batteries.

Claims

1. A process for coating a substrate with metal dichalcogenide by chemical vapor deposition from a single source precursor, comprising:

a) selecting as said precursor the reaction product of the halide of a metal, M, capable of forming a metal dichalcogenide, and an organic chalcogenide or dichalcogenide or mixture thereof, wherein said organic chalcogenide has the formula R¹ TR² and said organic dichalcogenide has the formula R¹ TTR², wherein T is a chalcogen selected from the group consisting of sulfur, selenium, and tellurium and mixtures thereof, and wherein R¹ and R² may be the same or different, and are substituted or unsubstituted organic radicals selected from the group consisting of linear or branched C_1-18 alkyl, linear or branched C_2-18 alkenyl, C_3-8 cycloalkyl, C_3-8 cycloalkenyl, and C_6-14 aryl radicals, or wherein R¹ and R² together form a C_3-8 cyclic diradical, or wherein R¹ and R² are selected from organic germanyl radicals, silyl radicals, and stannyl radicals;

b) subliming said precursor at a pressure of less than about 760 mm Hg; and

c) contacting said sublimed precursor with a substrate maintained at a temperature sufficient to effect decomposition of said precursor to metal dichalcogenide, whereby a coating of metal dichalcogenide is formed on said substrate.

2. The process of claim 1 wherein said metal halide has the formula MX₄.

3. The process of claim 2 wherein said metal halide has the formula MCl₄.

4. The process of claim 1 wherein said metal halide is a metal chloride.

5. The process of claim 1 wherein said metal is selected from the group consisting of titanium, zirconium, and hafnium.

6. The process of claim 1, wherein said subliming takes place at a pressure of from 0.001 mm Hg to 1 mm Hg, and wherein said substrate is maintained at a temperature of from 300°

C. to 700°

C.

7. The process of claim 1 wherein said sublimed precursor is first contacted with an inert gas stream flowing in the direction of the substrate to be coated.

8. The process of claim 1 wherein R¹ and R² are selected from the group consisting of methyl, ethyl, propyl, butyl, t-butyl, and phenyl, and when R¹ and R² together form a cyclic diradical, said diradical is selected from the group consisting of trimethylene, tetramethylene, and pentamethylene.

9. The process of claim 1 wherein said precursor has an empirical formula selected from the group consisting of

10. The process of claim 9 wherein M is selected from the group consisting of titanium, zirconium, and hafnium and X is chlorine.

11. The process of claim 1 wherein said coating comprises a metal disulfide, and wherein said single source precursor comprises the reaction product of a titanium (IV) halide with an organic chalcogen compound selected from the group consisting of dimethyldisulfide, tetrahydrothiophene, pentamethylene sulfide, and dimethylsulfide.

12. The process of claim 1 wherein said coating comprises a metal diselenide and wherein said single source precursor comprises the reaction product of a titanium (IV) halide and dimethylselenide.

13. The process of claim 1 wherein said coating comprises a metal ditelluride and wherein said single source precursor comprises the reaction product of a titanium (IV) halide and diphenylditelluride.