TITLE:
An Electrochemical Nitrite Sensor Based on a Multilayer Film of Polyoxometalate
AUTHORS:
Yosra Sahraoui, Sana Chaliaa, Abderrazak Maaref, Amor Haddad, Nicole Jaffrezic-Renault
KEYWORDS:
Nitrite Sensor; Polyoxometalate; Mono-Lacunary Keggin Anion; Layer by Layer Assembly Process
JOURNAL NAME:
Journal of Sensor Technology,
Vol.3 No.3,
September
12,
2013
ABSTRACT: In this work, we have developed an electrochemical sensor for nitrite detection, based on a polyoxometalate (POM) namely mono-lacunary keggin anion [SiW11O39]8﹣ cited as (SiW11). Electrochemical characterization of SiW11 shows two-step reduction processes, with formal potentials of ﹣0.5 V (I) and ﹣0.68 V (II). Oppositely charged polyelectrolyte (poly (allylamine hydrochloride) (PAH)) and (SiW11) were assembled alternately to modify glassy carbon electrode. The electrochemical behavior of the modified electrode was studied in detail using cyclic voltammetry (CV). The results showed that SiW11/PAH/GC electrode present good electrocatalytic activity for the reduction of nitrite. The sensor showed a dynamic range from 100 μM to 3.6 mMof nitrite and no interference from other classical anions. Experimental factors that affect electron-transfer rate in these films, such as pH effect and layers number, were systematically analyzed.