Facile Fabrication of CeO2/Electrochemically Reduced Graphene Oxide Nanocomposites for Vanillin Detection in Commercial Food Products

Abstract

In this paper, CeO2 nanoparticles were synthesized by the solvothermal method and dispersed uniformly in graphene oxide (GO) aqueous solution by ultrasonication. The homogeneous CeO2-GO dispersion was coated on the surface of a glassy carbon electrode (GCE), and the CeO2/electrochemically reduced graphene oxide modified electrode (CeO2/ERGO/GCE) was obtained by potentiostatic reduction. The results of X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) showed that CeO2 nanocrystals were uniformly coated by gossamer like ERGO nanosheets. The electrochemical behavior of vanillin on the CeO2/ERGO/GCE was studied by cyclic voltammetry (CV). It was found that the CeO2/ERGO/GCE has high electrocatalytic activity and good electrochemical performance for vanillin oxidation. Using the second derivative linear sweep voltammetry (SDLSV), the CeO2/ERGO/GCE provides a wide range of 0.04–20 µM and 20 µM–100 µM for vanillin detection, and the detection limit is estimated to be 0.01 µM after 120 s accumulation. This method has been successfully applied to the vanillin detection in some commercial foods.

Nickel Nanoparticles Supported on Nitrogen-Doped Carbon for Vanillin Detection

“…From the slope of the curve, it can be calculated that the value of α n is 1.147. For the completely irreversible electrode process, α is usually 0.5, and then the electron-transfer number n = 2, which is identical with the previous reports. ,− The reaction mechanism of vanillin has also been investigated in detail in our previous reports. , Based on the results obtained in this work and previous studies, we believe the electron-transfer mechanism of vanillin on the Ni NPs/N–C/CPE can be illustrated as Scheme .…”

Simultaneous Determination of Ferulic Acid and Vanillin in Vanilla Extracts Using Voltammetric Sensor Based on Electropolymerized Bromocresol Purple

“…According to the Tafel plots at the low-potential scan rates [ 28 ], the anodic transfer coefficients of 0.52 and 0.47 were calculated for ferulic acid and vanillin, respectively. The number of electrons participating in electrooxidation was obtained from Equation (1) [ 28 ] and is equal to 2.2 for ferulic acid and 2.3 for vanillin, which is in line with what is reported in [ 16 , 32 , 33 , 34 , 35 , 36 , 37 , 38 ]. ∆ E 1/2 =47.7/α a n …”

Highly Sensitive Voltammetric Sensor for Nanomolar Dopamine Detection Based on Facile Electrochemical Reduction of Graphene Oxide and Ceria Nanocomposite

“…[29][30][31] Recently, some electrochemical sensors based on ceria-GR nanocomposites have been reported. [32][33][34][35][36][37] For example, Zhu and co-workers prepared a non-enzymatic nanocomposite of heteropolyacids and CeO 2 @Pt alloy nanoparticles doped reduced graphene oxide (rGO) and investigated its electrochemical performances towards the simultaneous determination of xanthine and uric acid. 32 Chaturvedi et al developed nanoceria-nanoplatinum-GR hybrid nanocomposite as a base transducing layer for mediator-free enzymatic biosensors.…”

“…34 Hu and co-workers construct a highly sensitive realtime electrochemical sensing platform for NO detection based on shape-controlled ceria-rGO nanocomposites. 35 Nie et al fabricated a CeO 2 nanoparticles-GR composite modified electrode for the sensitive detection of tryptophan 36 and vanillin. 37 The combination of ceria nanoparticles with GR nanosheets has been demonstrated to produce synergistic effect, so as to enhance catalytic activity, improve the stability and conductivity of ceria nanoparticles.…”