Microporous carbon and method for making the same

Abstract

A carbon material includes a carbonized composite formed from a substantially homogeneous composite including a carbon precursor and an activation agent that is soluble in a solution including the carbon precursor. Micropores having a substantially uniform size distribution are formed throughout the carbonized composite. At least 90% of a total pore volume of the carbon material is composed of micropores, and 10% or less of the total pore volume is composed of mesopores and macropores. A surface area of the carbon material ranges from about 1400 m 2 /g to about 3000 m 2 /g.

1 . A carbon material, comprising:
 a carbonized composite formed from a substantially homogeneous composite including a carbon precursor and an activation agent that is soluble in a solution including the carbon precursor; and   micropores having a substantially uniform size distribution formed throughout the carbonized composite;   wherein at least 90% of a total pore volume of the carbon material is composed of micropores, and 10% or less of the total pore volume is composed of mesopores and macropores, and wherein a surface area of the carbon material ranges from about 1400 m 2 /g to about 3000 m 2 /g.   
     
     
         2 . The carbon material as defined in  claim 1  wherein the carbon precursor is a phenolic resin oligomer, resorcinol, or a phloroglucinol based resin oligomer, and wherein the activation agent is selected from potassium hydroxide, sodium hydroxide, potassium carbonate, and sodium carbonate. 
     
     
         3 . The carbon material as defined in  claim 1  wherein hydrogen absorption capacity of the carbon material ranges from about 2.8 wt.% to about 5.75 wt.% at pressures above 25 bar and at about 77 K. 
     
     
         4 . The carbon material as defined in  claim 1  wherein a weight ratio of the activation agent to the carbon precursor ranges from 1 to 3. 
     
     
         5 . A method for using the carbon material as defined in  claim 1 , comprising incorporating the carbon material into a device as a hydrogen storage medium, a catalyst support, an adsorbent, or an electrode. 
     
     
         6 . A method for making microporous carbon, comprising:
 preparing a carbon precursor solution;   mixing an activation agent in the carbon precursor solution to form a substantially homogeneous mixture;   polymerizing the substantially homogeneous mixture, thereby forming a substantially homogeneous composite; and   substantially simultaneously carbonizing and activating the substantially homogeneous composite.   
     
     
         7 . The method as defined in  claim 6  wherein the carbon precursor solution is prepared by reacting phenol with formaldehyde in a liquid medium in the presence of a catalyst. 
     
     
         8 . The method as defined in  claim 7  wherein the liquid medium includes water or a mixture of water and ethanol. 
     
     
         9 . The method as defined in  claim 8  wherein the activation agent is selected from potassium hydroxide, sodium hydroxide, potassium carbonate, and sodium carbonate. 
     
     
         10 . The method as defined in  claim 6 , further comprising controlling a surface area of the microporous carbon by controlling an amount of the activation agent mixed in the carbon precursor solution. 
     
     
         11 . The method as defined in  claim 6  wherein mixing includes stirring the activation agent in the carbon precursor solution, and wherein the method further comprises heating the substantially homogeneous composite prior to carbonizing. 
     
     
         12 . The method as defined in  claim 6  wherein carbonizing and activating are accomplished by heating the substantially homogeneous composite to a temperature ranging from about 500° C. to about 900° C. under an inert atmosphere for a predetermined time period ranging from about 0.5 hours to about 8 hours. 
     
     
         13 . The method as defined in  claim 6 , further comprising washing the substantially homogeneous carbonized composite. 
     
     
         14 . Microporous carbon formed by the process as defined in  claim 6 .