Copper oxide - Graphite composite electrodes: Application to nitrite sensing

A simple method for the modification of carbon powder with copper oxides is presented. Carbon powder is impregnated with copper(II) nitrate by stirring carbon powder in copper(II) nitrate solution for 1 hour and subsequently thermally treated at 823 K. The modified carbon powder was characterized using electrochemical and spectroscopic techniques. The existence of both copper(l) and copper(II) oxides have been established. The copper oxide modified carbon powder was used for preparation of composite electrodes, and the electrochemical and electrocatalytic behavior of the resulting composite electrodes was studied. The copper oxide modified carbon powder - epoxy composite electrodes showed a high electrocatalytic activity for the nitrite detection in aqueous media, with the detection limit comparable or lower than detection limits obtained with other electrochemical sensors.