Electrochemical Reduction Behavior of Nitrobenzene at Carboxylated Multiwall Carbon Nanotubes Modified Glassy Carbon Electrode

Electrochemical behaviour of nitrobenzene at the GCE modified with carboxylated multwall carbon nanotubes was studied and its mechanism of electrochemical reduction was discussed.It was found that in 0.2 mol·L-1 H2SO4 solution,the reduction of nitrobenzene at the modified electrode was remarkably catalyzed,showing a positive shift of the reductive peak potential of 90 mV as from -0.44 V (at the bare GCE) to -0.35 V (at the modified electrode of CMWCNT′s/GCE) and a negative shift of the oxidative peak potential of 50 mV as from 0.35 V (at the bare GCE) to 0.30 V (at the modified GCE).Cyclic voltammetric determination of nitrobenzene was performed in the linearity range of 5.0×10-7-4.2×10-5mol·L-1 in respective to the values of reductive peak current.Value of detection limt (3S/N) found was 8.2×10-8mol·L-1.Using the sample of lake water as matrix,test for recovery was made by standard addition method,and values of recovery found were in the range of 98.3%-100.6%.