催化学报

催化学报 ›› 2012, Vol. 33 ›› Issue (3): 487-493.DOI: 10.1016/S1872-2067(11)60349-5

• 研究论文 • 上一篇    下一篇

New Modified-Multiwall Carbon Nanotubes Paste Electrode for Electrocatalytic Oxidation and Determination of Hydrazine Using Square Wave Voltammetry

Ali A. ENSAFI*, Mahsa LOTFI, Hassan KARIMI-MALEH   

  1. Department of Chemistry, Isfahan University of Technology, Isfahan 84156-83111, Iran
  • 收稿日期:2011-08-30 修回日期:2011-11-30 出版日期:2012-03-15 发布日期:2015-07-27

New Modified-Multiwall Carbon Nanotubes Paste Electrode for Electrocatalytic Oxidation and Determination of Hydrazine Using Square Wave Voltammetry

Ali A. ENSAFI*, Mahsa LOTFI, Hassan KARIMI-MALEH   

  1. Department of Chemistry, Isfahan University of Technology, Isfahan 84156-83111, Iran
  • Received:2011-08-30 Revised:2011-11-30 Online:2012-03-15 Published:2015-07-27

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摘要： The application of p-aminophenol as a suitable mediator, as a sensitive and selective voltammetric sensor for the determination of hydrazine using square wave voltammetric method were described. The modified multiwall carbon nanotubes paste electrode exhibited a good electrocatalytic activity for the oxidation of hydrazine at pH = 7.0. The catalytic oxidation peak currents showed a linear dependence of the peaks current to the hydrazine concentrations in the range of 0.5–175 μmol/L with a correlation coefficient of 0.9975. The detection limit (S/N = 3) was estimated to be 0.3 μmol/L of hydrazine. The relative standard deviations for 0.7 and 5.0 µmol/L hydrazine were 1.7 and 1.1%, respectively. The modified electrode showed good sensitivity and selectivity. The diffusion coefficient (D = 9.5 × 10–4 cm2/s) and the kinetic parameters such as the electron transfer coefficient (α = 0.7) of hydrazine at the surface of the modified electrode were determined using electrochemical approaches. The electrode was successfully applied for the determination of hydrazine in real samples with satisfactory results.

关键词: hydrazine determination, modified carbon nanotubes paste electrode, electrocatalytic measurement, voltammetry

Abstract: The application of p-aminophenol as a suitable mediator, as a sensitive and selective voltammetric sensor for the determination of hydrazine using square wave voltammetric method were described. The modified multiwall carbon nanotubes paste electrode exhibited a good electrocatalytic activity for the oxidation of hydrazine at pH = 7.0. The catalytic oxidation peak currents showed a linear dependence of the peaks current to the hydrazine concentrations in the range of 0.5–175 μmol/L with a correlation coefficient of 0.9975. The detection limit (S/N = 3) was estimated to be 0.3 μmol/L of hydrazine. The relative standard deviations for 0.7 and 5.0 µmol/L hydrazine were 1.7 and 1.1%, respectively. The modified electrode showed good sensitivity and selectivity. The diffusion coefficient (D = 9.5 × 10–4 cm2/s) and the kinetic parameters such as the electron transfer coefficient (α = 0.7) of hydrazine at the surface of the modified electrode were determined using electrochemical approaches. The electrode was successfully applied for the determination of hydrazine in real samples with satisfactory results.

Key words: hydrazine determination, modified carbon nanotubes paste electrode, electrocatalytic measurement, voltammetry