Method of preparing an electrode for a capacitive deionization device, an electrode for a capacitive deionization device, and a capacitive deionization device having the electrode

Abstract

A method of preparing an oxidized electrode for a capacitive deionization device, the method including electrochemically oxidizing an electrode including a hydrophobic active material to produce the oxidized electrode.

1 . A method of manufacturing an oxidized electrode for a capacitive deionization device, the method comprising:
 electrochemically oxidizing an electrode comprising a hydrophobic active material to produce the oxidized electrode.   
     
     
         2 . The method of  claim 1 , wherein the electrode further comprises a binder and a conducting agent. 
     
     
         3 . The method of  claim 2 , wherein the electrode is prepared using a powdered hydrophobic active material. 
     
     
         4 . The method of  claim 1 , wherein the hydrophobic active material comprises a carbonaceous material. 
     
     
         5 . The method of  claim 4 , wherein the carbonaceous material comprises at least one selected from the group consisting of activated carbon, carbon nanotube, mesoporous carbon, activated carbon fiber, graphite, and graphite oxide. 
     
     
         6 . The method of  claim 5 , wherein the graphite comprises high surface area graphite. 
     
     
         7 . The method of  claim 1 , wherein the electrochemical oxidization of the electrode is performed in an electrochemical cell comprising the electrode, a counter electrode, an electrolyte solution in which the electrode and the counter electrode are immersed, and a separator which electrically insulates the electrode from the counter electrode,
 wherein the electrode is used as a positive electrode, and the counter electrode is used as a negative electrode in the electrochemical cell.   
     
     
         8 . The method of  claim 7 , wherein the electrode and the counter electrode are the same or different from each other. 
     
     
         9 . The method of  claim 7 , wherein the electrode and the counter electrode are the same. 
     
     
         10 . The method of  claim 7 , wherein the electrode and the counter electrode are different from each other. 
     
     
         11 . The method of  claim 7 , wherein the electrolyte solution is an acidic, alkaline, or neutral solution. 
     
     
         12 . The method of  claim 7 , wherein the electrolyte solution is an acidic solution. 
     
     
         13 . The method of  claim 7 , wherein the electrolyte solution is an alkaline solution. 
     
     
         14 . The method of  claim 7 , wherein the electrolyte solution is a neutral solution. 
     
     
         15 . The method of  claim 7 , wherein an amount of electric charge charged in the electrochemical cell during the electrochemically oxidizing the electrode is about 20 to about 30,000 coulombs per gram, based on a weight of an active material of the electrode. 
     
     
         16 . The method of  claim 7 , wherein a contact angle between the electrode and a hydrophilic electrolyte solution is decreased by the electrochemical oxidization of the electrode. 
     
     
         17 . The method of  claim 1 , further comprising washing the electrochemically oxidized electrode with a cleaning solution. 
     
     
         18 . An electrode for a capacitive deionization device, the electrode comprising:
 an electrochemically oxidized active material.   
     
     
         19 . The electrode of  claim 18 , further comprising an acidic functional group on the electrode. 
     
     
         20 . The electrode of  claim 19 , wherein the amount of the acidic functional group per unit weight of the electrode is about 0.7 to about 5 millimoles per gram. 
     
     
         21 . The electrode of  claim 19 , wherein the acidic functional group comprises at least one selected from the group consisting of a carboxyl group, a carboxylate group, and a phenol group. 
     
     
         22 . A capacitive deionization device comprising the electrode of  claim 18 .