SCI和EI收录∣中国化工学会会刊

中国化学工程学报 ›› 2020, Vol. 28 ›› Issue (10): 2555-2565.DOI: 10.1016/j.cjche.2020.04.017

• Catalysis, Kinetics and Reaction Engineering • 上一篇    下一篇

Green bio-synthesis of Ni/montmorillonite nanocomposite using extract of Allium jesdianum as the nano-catalyst for electrocatalytic oxidation of methanol

Mohammad Hossein Sheikh-Mohseni1, Sajjad Sedaghat2, Pirouz Derakhshi3, Aliakbar Safekordi1   

  1. 1 Department of Chemistry, Science and Research Branch, Islamic Azad University, Tehran, Iran;
    2 Department of Chemistry, Shahr-e-Qods Branch, Islamic Azad University, Shahr-e-Qods, Iran;
    3 Department of Chemistry, North Tehran Branch, Islamic Azad University, Tehran, Iran
  • 收稿日期:2019-12-28 修回日期:2020-03-28 出版日期:2020-10-28 发布日期:2020-12-03
  • 通讯作者: Sajjad Sedaghat

Green bio-synthesis of Ni/montmorillonite nanocomposite using extract of Allium jesdianum as the nano-catalyst for electrocatalytic oxidation of methanol

Mohammad Hossein Sheikh-Mohseni1, Sajjad Sedaghat2, Pirouz Derakhshi3, Aliakbar Safekordi1   

  1. 1 Department of Chemistry, Science and Research Branch, Islamic Azad University, Tehran, Iran;
    2 Department of Chemistry, Shahr-e-Qods Branch, Islamic Azad University, Shahr-e-Qods, Iran;
    3 Department of Chemistry, North Tehran Branch, Islamic Azad University, Tehran, Iran
  • Received:2019-12-28 Revised:2020-03-28 Online:2020-10-28 Published:2020-12-03
  • Contact: Sajjad Sedaghat

摘要: In this work, synthesis of Ni nanoparticles was carried out successfully by water extract of Allium jesdianum as a biochemical reducing agent in the presence of montmorillonite clay (MMT) as a natural solid support for the first time. Then the electrochemical activity of the synthesized nanocomposite was investigated in methanol electrocatalytic oxidation. MMT with high cation exchange capacity and nano layer structure was exposed to ion exchange conditions in nickel solution. Then Ni2+ ion exchanged form was used in this process as a source of ions and also capping agent. Water extract of Allium jesdianum used as a reducing agent due to abundant availability of phenolic and flavonoid contents. The synthesized Ni/MMT nanocomposite was characterized using UV-Vis spectroscopy (UV-Vis), Fourier Transform Infrared Spectroscopy (FT-IR), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission electron microscopy (TEM) and Energy-dispersive X-ray spectroscopy (EDX). The surface of prepared modified electrode has been characterized using SEM to evaluate the morphology, showing uniform dispersion of Ni nanoparticles with mean diameter of 12 to 20 nm. The modified carbon paste electrode was then used in methanol electrocatalytic oxidation reaction. Methanol oxidation on the proposed modified electrode surface occurs at 0.6 V and 0.3 V in alkaline and acidic medium respectively. Also, the results showed the better performance of modified electrode toward methanol electrocatalytic oxidation in comparison with carbon paste electrode that is modified by ion exchanged MMT. Charge transfer coefficients and apparent charge transfer rate constant for the modified electrode in the absence of methanol in alkaline medium were respectively found as: αa = 0.53, αc = 0.37 and ks = 1.6×10-1 s-1. Also, the average value of catalytic rate constant for the electrocatalytic oxidation of methanol by the prepared nano-catalyst was estimated to be about 0.9 L·mol-1·s-1 by chronoamperometry technique. The prepared electrode was also effective for electrocatalytic oxidation of ethanol and formaldehyde in alkaline medium.

关键词: Green biosynthesis, Nanoparticles, Montmorillonite, Biocatalysis, Methanol electrocatalytic oxidation, Fuel cell

Abstract: In this work, synthesis of Ni nanoparticles was carried out successfully by water extract of Allium jesdianum as a biochemical reducing agent in the presence of montmorillonite clay (MMT) as a natural solid support for the first time. Then the electrochemical activity of the synthesized nanocomposite was investigated in methanol electrocatalytic oxidation. MMT with high cation exchange capacity and nano layer structure was exposed to ion exchange conditions in nickel solution. Then Ni2+ ion exchanged form was used in this process as a source of ions and also capping agent. Water extract of Allium jesdianum used as a reducing agent due to abundant availability of phenolic and flavonoid contents. The synthesized Ni/MMT nanocomposite was characterized using UV-Vis spectroscopy (UV-Vis), Fourier Transform Infrared Spectroscopy (FT-IR), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission electron microscopy (TEM) and Energy-dispersive X-ray spectroscopy (EDX). The surface of prepared modified electrode has been characterized using SEM to evaluate the morphology, showing uniform dispersion of Ni nanoparticles with mean diameter of 12 to 20 nm. The modified carbon paste electrode was then used in methanol electrocatalytic oxidation reaction. Methanol oxidation on the proposed modified electrode surface occurs at 0.6 V and 0.3 V in alkaline and acidic medium respectively. Also, the results showed the better performance of modified electrode toward methanol electrocatalytic oxidation in comparison with carbon paste electrode that is modified by ion exchanged MMT. Charge transfer coefficients and apparent charge transfer rate constant for the modified electrode in the absence of methanol in alkaline medium were respectively found as: αa = 0.53, αc = 0.37 and ks = 1.6×10-1 s-1. Also, the average value of catalytic rate constant for the electrocatalytic oxidation of methanol by the prepared nano-catalyst was estimated to be about 0.9 L·mol-1·s-1 by chronoamperometry technique. The prepared electrode was also effective for electrocatalytic oxidation of ethanol and formaldehyde in alkaline medium.

Key words: Green biosynthesis, Nanoparticles, Montmorillonite, Biocatalysis, Methanol electrocatalytic oxidation, Fuel cell