Co2TiO4/Reduced Graphene Oxide Nanohybrids for Electrochemical Sensing Applications

VENEGAS, CONSTANZA J.; GUTIERREZ, FABIANA A.; EGUÍLAZ, MARCOS; MARCO, JOSÉ F.; REEVES-MCLAREN, NIK; RIVAS, GUSTAVO A.; RUIZ-LEÓN, DOMINGO; BOLLO, SOLEDAD

Nanomaterials

MDPI

Año: 2019 vol. 9

Abstract: For the first time, the synthesis, characterization, and analytical application for hydrogenperoxide quantification of the hybrid materials of Co2TiO4 (CTO) and reduced graphene oxide (RGO)is reported, using in situ (CTO/RGO) and ex situ (CTO+RGO) preparations. This synthesis forobtaining nanostructured CTO is based on a one-step hydrothermal synthesis, with new precursorsand low temperatures. The morphology, structure, and composition of the synthesized materials wereexamined using scanning electron microscopy, X-ray diffraction (XRD), neutron powder diffraction(NPD), and X-ray photoelectron spectroscopy (XPS). Rietveld refinements using neutron diffractiondata were conducted to determine the cation distributions in CTO. Hybrid materials were alsocharacterized by Brunauer?Emmett?Teller adsorption isotherms, Scanning Electron microscopy,and scanning electrochemical microscopy. From an analytical point of view, we evaluated theelectrochemical reduction of hydrogen peroxide on glassy carbon electrodes modified with hybridmaterials. The analytical detection of hydrogen peroxide using CTO/RGO showed 11 and 5 timesgreater sensitivity in the detection of hydrogen peroxide compared with that of pristine CTO and RGO,respectively, and a two-fold increase compared with that of the RGO+CTO modified electrode. Theseresults demonstrate that there is a synergistic effect between CTO and RGO that is more significantwhen the hybrid is synthetized through in situ methodology.