CHRONO AMPEROMETRIC DETERMINATION OF HYDROGEN-PEROXIDE IN SWIMMING POOL WATER USING AN ULTRAMICROELECTRODE ARRAY

Ultramicroelectrode arrays have been applied for monitoring the disinf ectant hydrogen peroxide in swimming pool water. The sensors were manu factured using silicon thin-film technology. Each consisted of nine mi niaturized platinum working electrodes connected in parallel. A platin um counter electrode and a silver/silver chloride reference electrode completed the measuring setup. The ultramicroelectrode arrays were cha racterized by cyclic voltammetry and chrono amperometry. The sensor pr operties could be improved and the interfering influence of the swimmi ng pool water matrix was reduced by covering the working electrodes of the arrays with NAFION(TM) membranes. A comparison of the introduced chrono amperometric method using the ultramicroelectrode array with th e German standard method (DIN) for the hydrogen peroxide determination showed that the accuracy of the NAFION(TM) coated sensors is suitable for monitoring and controlling the hydrogen peroxide concentration in swimming pool waters. (C) 1998 Elsevier Science S.A. All rights reser ved.