Investigation on a new analytical method for determination of Vanadate(V) based on the combination of electrochemical parallel catalytic wave effect and chemiluminescence signal sensing

It was found that,in the presence of hydrogen peroxide in alkaline medium,vanadate(Ⅴ) could be reduced at the surface of the graphite electrode,giving parallel catalytic wave effect.Further study indicated that,butyl-rhodamine B can react with the reagent produced through vanadate(Ⅴ) catalyzing the reduction of hydrogen peroxide to emit a sensitive CL signal.The electrochemical reaction rate and chemiluminescence reaction rate of this system were measured,and the possibility of the combination of electrochemical parallel catalytic wave effect with chemiluminescence was proved.Based on these findings,a novel electrogenerated chemiluminescence method for the determination of vanadate(Ⅴ) was developed.At the same time,a new concept was also proposed for improving the sensitivity of electrochemical analysis based on the combination of electrochemical parallel catalytic wave effect and chemiluminesence signal sensing.Under the optimum experimental conditions,the linear range was 4.0×10-7 mol/L～8.0×10-5 mol/L for vanadate(Ⅴ).The detection limit was 3×10-8 mol/L.