Optimization study of large electrochemical active area of nanocomposites VACNT-GO and its application in capacitive deionization

Abstract

The aim of this work is to study and develop a composite of Vertically Aligned Carbon Nanotubes with Graphene Oxide (VACNT-GO) on large surfaces areas (up to 70 x 300 mm2) with high specific capacitance, in order to employ this material in capacitive deionization processes (CDI), focusing on treating water by removing pollutants ions (heavy metals, nitrates and nitrites, for example). Depending on the parameters that will be obtained (deionization efficiency and energy efficiency), the study of brackish water desalination or even sea water desalination can become the objective of this project. The study will involve: (a) the growth of highly crystalline VACNT, using thermal CVD process with floating catalyst; (b) the study of appropriate substrates, which must have high electrical conductivity and low contact resistance with the nanotubes to reduce ohmic loss in charging and discharging processes ions; (c) the study of oxidation methods to increase the exfoliation volume of VACNT for the VACNT-GO formation; (d) the study of CDI settings that allow the capillary pumping due to the VACNT-GO superhydrophilicity properties, to deionization studies in small volumes, developing a method of "lab on a chip" and (e) the construction of an CDI system to evaluate the deionization efficiency and energy efficiency in a desalination process. (AU)