Synthesis and characterization of LaMnO3 nanocrystals and graphene oxide: fabrication of graphene oxide–LaMnO3 sensor for simultaneous electrochemical determination of hydroquinone and catechol

Mohammad Mehdi Foroughi,Sedighe Akbari,Shohreh Jahani,Hadi Hassani Nadiki

doi:10.5599/jese.634

Abstract

For the first time, a new method for preparation of graphene oxide-LaMnO3 (GO-LaMnO3) nanocompositeas a material of electrochemical sensor for simultaneous determination of catechol (CT) and hydroquinone (HQ) is developed. LaMnO3 nanoparticles have been characterized by Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM) and energy dispersive X-ray analysis (EDX) technique. Due to the excellent catalytic activity, enhanced electrical conductivity and high surface area, the simultaneous determination of HQ and CT with two well-defined peaks has been achieved at the GO-LaMnO3 modified electrode. Comparing with unmodified electrodes, the oxidation currents of HQ and CT increased remarkably. Also, the result exhibited a great decrease in anodic overpotentialresulting in about 150 mV negative shift of potential. The catalytic peak current values are found linearly dependent on the HQ and CT concentrations in the range of 0.5–433.3 and 0.5–460.0 μM with sensitivity of 0.0719 and 0.0712 μA μM-1, respectively. The detection limits for HQ and CT are determined as 0.06 and 0.05 μM, respectively.

Highlights

Phenolic materials compounds are widely used in a broad class of industries, such as coal mining, cosmetics, paint, pharmaceutical preparation and polymer [1]
We have evaluated analytical performance of this sensor for simultaneous determination of HQ and CT by the voltammetry technique
The intense peak at 1710 cm-1 was derived from the existence of the C=O stretch and the band at 1285 cm-1 exhibits the presence of the C–O stretch

Summary

Introduction

Phenolic materials compounds are widely used in a broad class of industries, such as coal mining, cosmetics, paint, pharmaceutical preparation and polymer [1]. BGCE electrode showed a weak and broad oxidation peak for a mixture of HQ and CT at 0.33 V (curve a in Figure 3) suggesting slow electron transfer kinetics.

Results

Conclusion