Enzyme-free H2O2 Sensing at ZnO-Graphene Oxide-modified Glassy Carbon Electrode

摘要

The detection of hydrogen peroxide(H2O2)is of great importance,because it is an essential substrate in textile,mining,clinical,pharmaceutical,and food industries and also an end product of different enzymatic reactions in humans.Numerous analytical methods such as spectrophotometric,titrimetric,chromatographic,colorimetric,and electrochemical techniques have been employed for monitoring and detection of H2O2.Among them,the enzyme-free electrochemical method is of particular interest because of its low cost,ease of operation,and in situ quantification.Unfortunately,the kinetics of electrochemical oxidation-reduction of H2O2 over conventional working electrode surfaces is very slow owing to large overpotentials,which restricts its commercial applications.12-14 Therefore,chemically modified electrodes containing specifically selected redox substrates have been studied with a view to enhance the electrochemical response of H2O2.