Effective desalination by capacitive deionization with functional graphene nanocomposite as novel electrode material

In this work, functional graphene nanocomposite (reduced graphite oxidate-resol like material, named RGO-RF) was successfully synthesized and used as electrode in capacitive deionization (CDI) process. The porosity, morphology and electrochemical characteristics of RGO-RF were confirmed by N-2 adsorption-desorption curve, transmission electron microscopy and cyclic voltammetry, respectively. Further, the deionization performances of the RGO-RF electrode, reduced graphite oxidate (RGO) and activated carbon (AC) were examined for comparison by a lab-scale CDI experimental system. It is found that the RGO-RF shows the best deionization performance among the three target materials, indicating that it is a novel electrode material which has a great potential as effective electrode for CDI. Besides, the electrosorption isotherms and electrosorption kinetics were studied, and it is found that the ion sorption behaviour of RGO-RF follows a Langmuir adsorption isotherm, implying monolayer adsorption. (C) 2012 Elsevier B.V. All rights reserved.