Production process for nanometer-size silicon material

Patent metadata

Field	Value
Publication number	US-9527748-B2
Application number	US-201314441883-A
Country	US
Kind code	B2
Filing date	Nov 18, 2013
Priority date	Nov 21, 2012
Publication date	Dec 27, 2016
Grant date	Dec 27, 2016

Abstract

A nanometer-size silicon material produced by heat treating a lamellar polysilane exhibits Raman-shift peaks existing at 341±10 cm −1 , 360±10 cm −1 , 498±10 cm −1 , 638±10 cm −1 , and 734±10 cm −1 in a Raman spectrum, has a large specific surface area, and has a reduced SiO content.

First claim

The invention claimed is:

1. A production process for nanometer-size silicon material comprising: reacting a mixture of hydrogen fluoride (HF) and hydrogen chloride (HCl) with calcium disilicide (CaSi 2 ) to obtain a lamellar polysilane; and
heat treating the lamellar polysilane r at a temperature beyond 300° C. under a nonoxidizing atmosphere.

2. The production process for nanometer-size silicon material as set forth in claim 1 , wherein a nitrogen-gas atmosphere is excepted from said nonoxidizing atmosphere.

3. The production process for nanometer-size silicon material as set forth in claim 1 , wherein said nanometer-size silicon material has a specific surface area of 55 m 2 /g or less measured by a BET method.

4. The production process for nanometer-size silicon material as set forth in claim 1 , wherein said nanometer-size silicon material has a specific surface area of 25 m 2 /g or less measured by a BET method.

5. The production process for nanometer-size silicon material as set forth in claim 1 , wherein said nanometer-size silicon material includes oxygen in an amount of 30% by mass or less.

6. The production process for nanometer-size silicon material as set forth in claim 1 , wherein said nanometer-size silicon material includes oxygen in an amount of 15% by mass or less.

7. The production process for nanometer-size silicon material as set forth in claim 1 , wherein said nanometer-size silicon material includes oxygen in an amount of 10% by mass or less.

8. The production process for nanometer-size silicon material as set forth in claim 1 , wherein said nanometer-size silicon material has a crystallite size of from 1 nm to 50 nm, the crystallite size computed by the Scherrer equation from a half-value width of a diffraction peak in the (111) plane according to the result of an X-ray diffraction measurement.

Assignees

• Toyota Jidoshokki Kk

Inventors

• Sugiyama Yusuke
• Nakanishi Masataka
• Mori Takashi
• Murase Masakazu
• Niimi Tomohiro
• Nakagaki Yoshihiro
• Koishi Shigenori
• Hirate Hiroshi

Classifications

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title

• H01M4/134

  Electrodes based on metals, Si or alloys · CPC title

• C01P2004/64

  Nanometer sized, i.e. from 1-100 nanometer · CPC title

• H01M2004/027

  Negative electrodes · CPC title

• C08G77/60

  in which all the silicon atoms are connected by linkages other than oxygen atoms · CPC title