Ayalneh, Girum (PhD)Addis, Fitsum2018-07-122023-11-182018-07-122023-11-182017-05http://etd.aau.edu.et/handle/12345678/8375The rapid growth of the global population and industrial activities pose a great challenge to meeting ever-increasing energy demands. This thesis adapts a modified synthesis of graphene oxide (GO), an important starting material in graphene chemistry, convert graphene oxide back to graphene-like structure, and finally shows the electrochemical behavior poly (4-amino-3-hydroxynaphtalene sulfonic acid)/rGO composite and also demonstrates its possible application in electrocatalytic reduction of oxygen. In this work, the electrochemical, XRD, and FTIR analysis gave evidence for the formation of graphene oxide (GO) from graphite and the reduced graphene oxide (rGO) from GO. The electrocatalytic activity of the poly (4-amino-3-hydroxynaphtalene sulfonic acid)/rGO composite modified electrodes towards oxygen reduction reaction were studied. The p-(AHNSA) modified glassy carbon electrode shows a two-electron reduction of oxygen to hydrogen peroxide and the p-(AHNSA)/rGO modified glassy carbon electrode shows a direct four-electron reduction of oxygen to water. Koutecky-Levich plot analysis was used to predict the mechanism and evaluate the kinetic parameters.en4-Amino-3-Hydroxynaphtalene Sulfonic AcidThesis