Electrochemical behaviors of diphenyl carbazide on multi-wall carbon nanotubes modified glassy carbon electrode(MWCNT/GCE)were investigated by cyclic voltammetry(CV)、Chronocoulometry(CC)and Chronoamperometry(CA).The ...Electrochemical behaviors of diphenyl carbazide on multi-wall carbon nanotubes modified glassy carbon electrode(MWCNT/GCE)were investigated by cyclic voltammetry(CV)、Chronocoulometry(CC)and Chronoamperometry(CA).The experimental results showed that on MWCNT/GCE its oxidation currents increase with the potential shift positively,it appears an irreversible oxidation peak at 0.070V,and also the peak current increase greatly,which indicates that MWCNT/GCE can catalyze the electrochemical oxidation of diphenyl carbazide very well.It has also done the research on the influence of the experimental conditions on diphenyl carbazide electrochemical behaviors.It has showed that diphenyl carbazide electrochemical oxidation,which is a diffusion-limited electrode reaction process,at the same time the diffusion coefficient D,electron transfer coefficient α and the electrode reaction rate constant kf were gives the values of 6.5×10-5 cm2/s,0.865 and 6.7×10-3 cm/s.According to the experimental results of the amperometric i-t curve that current signal of MWCNT/GCE was proportional to diphenyl carbazide concentration,response time less than 4 seconds,and the lowest concentration is 1×10-6 mol/L,which can be used in diphenyl carbazide electrochemical quantity determination with both low detection limit and high sensitivity.展开更多
The method for the sepration and determination of trace Cr(VI) exiting in mass Cr(III) has been researched. The method is highly sensitive and less interference, but is simple and useful for analysis trace Cr(VI).
文摘Electrochemical behaviors of diphenyl carbazide on multi-wall carbon nanotubes modified glassy carbon electrode(MWCNT/GCE)were investigated by cyclic voltammetry(CV)、Chronocoulometry(CC)and Chronoamperometry(CA).The experimental results showed that on MWCNT/GCE its oxidation currents increase with the potential shift positively,it appears an irreversible oxidation peak at 0.070V,and also the peak current increase greatly,which indicates that MWCNT/GCE can catalyze the electrochemical oxidation of diphenyl carbazide very well.It has also done the research on the influence of the experimental conditions on diphenyl carbazide electrochemical behaviors.It has showed that diphenyl carbazide electrochemical oxidation,which is a diffusion-limited electrode reaction process,at the same time the diffusion coefficient D,electron transfer coefficient α and the electrode reaction rate constant kf were gives the values of 6.5×10-5 cm2/s,0.865 and 6.7×10-3 cm/s.According to the experimental results of the amperometric i-t curve that current signal of MWCNT/GCE was proportional to diphenyl carbazide concentration,response time less than 4 seconds,and the lowest concentration is 1×10-6 mol/L,which can be used in diphenyl carbazide electrochemical quantity determination with both low detection limit and high sensitivity.
文摘The method for the sepration and determination of trace Cr(VI) exiting in mass Cr(III) has been researched. The method is highly sensitive and less interference, but is simple and useful for analysis trace Cr(VI).