Synthesis, characterization and electrochemical-sensor applications of zinc oxide/graphene oxide nanocomposite

Abstract

Nanostructured metal oxides received considerable research attention due to their unique properties that can be used for designing advanced nanodevices. Thus, in the present study, zinc oxide/graphene oxide (ZnO/GO) nanocomposite was synthesized, characterized and implemented in an electrochemical system. The formation of a compacted ZnO/GO nanocomposite was confirmed by field emission scanning electron microscopy, high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), and attenuated total reflectance spectroscopy. HRTEM showed that ZnO nanocrystals (NCs) are well formed on the GO surface and are interconnected via GO functional groups. From the XRD patterns, the average size of ZnO NCs was found to be about 21.7 ± 2.3 nm which is in agreement with the HRTEM results. The newly developed nanocomposite-based electrochemical system showed a significant improvement in both electrical conductivity and the electrocatalytic activity as noted from the cyclic voltammetry measurements. Consequently, direct electron transfer efficiency was confirmed and used for the amperometric detection of hydrogen peroxide (H 2 O 2 ). Fast and sensitive electrochemical responses for the detection of H 2 O 2 at 1.1 V in the linear response range from 1 to 15 mM with the detection limit (S/N = 3) of 0.8 mM were obtained. These results demonstrated that the prepared ZnO/GO/CPE displayed a good performance along with high sensitivity and longterm stability.

Removal of Toxic Metal Ions From Potable Water by Graphene Oxide Composites

“…FTIR spectra (Figure A) of Zinc Oxide − Graphene Oxide (ZnO‐GO) shows vibration stretching of O–H around 3429 cm −1 while vibration peak at 2926 and 2856 cm −1 shows asymmetric stretching and symmetric CH 2 and minor peak with low intensity indicates CO stretching vibrations in the carboxyl group are also visible around 1618 cm −1 . XRD pattern of ZnO‐GO shows peaks at 20.35, 30.64, 31.52, 36.32 and 45.27° and a peak of GO at 11.16° was disappeared which indicate the synthesis of ZnO‐GO (Figure (B)) . TEM image clearly shows ZnO particles on GO layers (Figure (C)).…”

Effect of Annealing Temperature on ECD Grown Hexagonal-Plane Zinc Oxide

“…Additionally, excessive amounts of KCl could promote other growth species, such as KNO 3 and ZnCl 2 while 0.1 M is proven to be sufficient for the purpose of capping the (0001) plane [52]. Thus, 0.1 M was chosen as the standard growth condition in this work [45,53]. Through extraction of the reduction current (${\mathrm{I}}_{\mathrm{normalP}\left(\mathrm{re}\right)}$) and oxidation current (${\mathrm{I}}_{\mathrm{normalP}\left(\mathrm{ox}\right)}$) from Figure 3b into Figure 3c, there is a clear enhancement trend shown with increasing KCl concentration, while presented in Figure 3d is the ratio of ${\mathrm{I}}_{\mathrm{normalP}\left(\mathrm{ox}\right)}/{\mathrm{I}}_{\mathrm{normalP}\left(\mathrm{re}\right)}$, which remains relatively constant as a function of [KCl].…”

Review on Zinc Oxide-Graphene Oxide Nanocomposites: Synthesis Techniques, Properties and Applications

“…Ehab Salih et.al. [12] reported the synthesis of Zinc oxide/Graphene oxide (ZnO/GO) nanocomposite in an electrochemical system. The formation of a ZnO/GO nanocomposite was confirmed by HRTEM, XRD, FESEM and attenuated total reflectance spectroscopy.…”