Surface modified carbon felts were utilized as an electrode for the removal of inorganic ions from seawater. The surfaces of the carbon felts were chemically modified by alkaline and acidic solutions, respectively. The potassium hydroxide (KOH) modified carbon felt exhibited high Brunauer-Emmett-Teller (BET) surface areas and large pore volume, and oxygencontaining functional groups were increased during KOH chemical modification. However, the BET surface area significantly decreased by nitric acid (HNO3) chemical modification due to severe chemical dissolution of the pore structure. The capability of electrosorption by an electrical double-layer and the efficiency of capacitive deionization (CDI) thus showed the greatest enhancement by chemical KOH modification due to the appropriate increase of carboxyl and hydroxyl functional groups and the enlargement of the specific surface area.

Abstract
 1. Introduction
 2. Experimental
 3. Results and Discussion
  3.1. Surface characteristics of carbon felt electrode
  3.2. Electrochemical behaviors
  3.3. Capacitive deionization
 4. Conclusions
 References

• Han-Jun Oh(School of Advanced Materials Engineering, Sungkyunkwan University, Suwon 440-746, Korea) Corresponding author
• Young-Jig Kim(School of Advanced Materials Engineering, Sungkyunkwan University, Suwon 440-746, Korea)
• Jeong-Il Youn(School of Advanced Materials Engineering, Sungkyunkwan University, Suwon 440-746, Korea)
• Donghwan Cho(Department of Polymer Science and Engineering, Kumoh National Institute of Technology, Gumi 730-701, Korea)
• Hong-Joo Ahn(Nuclear Chemistry Section, Korea Atomic Energy Research Institute, Daejeon 305-600, Korea)
• Jong-Ho Lee(Departments of Chemistry and 5Materials Science, Hanseo University, Seosan 352-820, Korea)