Determination of Nitrite with the Modified Electrode of YbHS/MWCNT′s/GCE

The modified electrode was prepared by dropping a suspension of multiwall nanocarbon tubes (MWCNT′s) in a solution of ytterbium salt of heteropoly acid (YbHS) onto the surface of glassy carbon electrode (GCE),which is abbreviated as YbHS/MWCNT′s/GCE.The surface property of the modified electrodes was characterized by AC impedance method,and its electrochemical property was studied by cyclic voltammetry.It was found that nitrite ion showed an oxidation peak at the potential of -0.45 V.Based on these findings,a selective method for determination of nitrite by cyclic voltammetry was proposed.Linear relationship between values of peak current and concentration of NO-2 was ranged from 5.0×10-6 to 1.0×10-4mol·L-1.The proposed method was used in the analysis of environmental water samples,giving values of recovery in the range of 97.2%-98.0%.