Determination of Nitrite and Nitrogen Oxides by Anodic Voltammetry at Conductive Diamond Electrodes

Abstract

The oxidation of nitrite at boron-doped diamond (BDD) electrode was investigated by use of anodic voltammetry. The voltammetric curves exhibit well-defined anodic peaks, with response that is superior to that obtained with glassy carbon electrodes. The influence of pH, nitrite concentration, and potential sweep rate on the electrode response was thoroughly investigated. The results show that the measurement of the oxidation peak current can be used as the basis for a simple, accurate, rapid method for the determination of within a concentration range of 0.002-1 mM. Flow injection analysis with amperometric detection was also examined and improved sensitivity was observed, with analytical useful signals being obtained at 50 nM. The possibility of using anodic voltammetry for the determination of nitrogen oxides (NO and was also assessed. It is shown that BDD is a very promising electrode material for the detection of nitrogen oxides in gases and the determination of NO in aqueous solution. © 2001 The Electrochemical Society. All rights reserved.