Glassy Carbon Electrode Modified with Nickel (II) Tetrasulfophtalocyanine Films and its Behavior as Amperometric Sensor for Nitrite

摘要

In this work, a modification of a glassy carbon electrode with a film of Nickel (II)tetrasulfophtalocyanine (f-NiTSPc) was done, which was obtained by a continuous potential cycling inaqueous solution. It was found that a modified electrode with f-Ni(II)TSPc increases its activity versusnitrite oxidation, in comparison to the bare glassy carbon electrode (GC) and the monomer multilayersof this complex (m-Ni(II)TSPc). Its activity was studied versus different pH, and it was found that thebetter conditions for nitrite oxidation were at pH 7.2. At this pH kinetic calculations were done, findingthat it is a diffusional process with a one-electron transference and a Tafel-slope value of 59 mV/dec,postulating a possible reaction mechanism. Finally, the electrode behavior was studied as possibleamperometric sensor for nitrite, obtaining and calculating its analytical parameters such as accuracy,exactitude, detection and quantification limits, being a good method for nitrite quantification inaqueous solution.