Silicon-carbonaceous encapsulated materials

Abstract

A process includes preparing a solution including a silicon precursor or mixture of silicon precursors and a monomer or mixture of monomers; polymerizing the monomer to form a polymer-silicon precursor matrix; and pyrolyzing the polymer-silicon precursor matrix to form an electrochemically active carbon-coated silicon material.

What is claimed is: 
     
         1 . A process comprising:
 contacting a silicon compound with a carbon source gas at a temperature sufficient to degrade the carbon source gas to carbon and deposit the carbon on the surface of the silicon compound to form SiO 2 C or SiO x C, wherein x is less than 2 and greater than zero;   wherein:
 the silicon compound is silicon, a silicon suboxide, a silicon oxycarbide, or a mixture of any two or more such materials. 
   
     
     
         2 . The process of  claim 1 , wherein the silicon compound is SiO 2  produced by the Stöber method. 
     
     
         3 . The process of  claim 1 , wherein the temperature is from about 400° C. to about 1600° C. 
     
     
         4 . The process of  claim 1 , wherein the carbon source gas comprises a C 1 -C 12  alkane, a C 1 -C 12  alkene, a C 1 -C 12  alkyne, or a mixture of any two or more such gases. 
     
     
         5 . The process of  claim 1 , wherein the carbon source gas comprises methane, ethane, n-propane, n-butane, 2-methylpropane, n-pentane, 2-methylbutane, 2,2-dimethylpropane, hexane, ethylene, propylene, 1-butene, cis-2-butene, trans-2-butene, 2-methylpropene, 1,3-butadiene, 1-pentene, 2-pentene, 3-pentene, 2-methyl-l-butene, 2-methyl-2-butene, 3-methyl-l-butene, hexene, acetylene, acetylene, 1-butyne, 2-butyne, 1-pentyne, 2-pentyne, 3-methyl-1-pentyne, hexyne, or toluene. 
     
     
         6 . An anode material comprising the electrochemically active carbon-coated silicon material produced according to  claim 1 . 
     
     
         7 . An anode material comprising the SiO 2 C or SiO x C produced according to  claim 1 . 
     
     
         8 . An electrochemical device comprising the anode material of  claim 6 . 
     
     
         9 . An electrochemical device comprising the anode material of  claim 7 .