Electrical charge distribution on carbon surfaces as a function of the pH and point of zero charge. An approximate solution

Abstract

Knowing whether a carbon surface is positively or negatively charged (and to what extend) depending on the characteristics of the medium in which is dispersed could be useful for certain applications of the carbon. In particular, for the electrochemical applications of carbon materials, like electrodes for EDL capacitors, anodes for batteries, etc. This is, however, a non straightforward issue since the charges developed in a carbon surface depends both on its, generally complex, surface chemistry and, on the characteristics of the medium in which is embedded (i.e. pH). In this work some assumptions are made in order to simplify de problem and to come out with an approximate solution.