INMA researchers monitor the transformation of the structure, composition and electrical conduction of graphene oxide with temperature
Graphene oxide is a material with a structure similar to that of graphene, with a wide and diverse field of applications. To make use of its potential, the team of researchers led by Raúl Arenal, ARAID researcher at the Institute of Nanoscience and Materials of Aragon, INMA, a joint centre between the CSIC and the University of Zaragoza and the Advanced Microscopy Laboratory, LMA – University of Zaragoza, have managed to study, for the first time at the nano scale, the variation in the structure of this material with increasing temperature and to monitor how its electrical conductivity changes with these variations, going from being an insulating material to a conductive one.
Graphene oxide is a two-dimensional nanomaterial (lamellar) with a structure close to that of graphene, but with a large number of functional groups and water (physisorbed and chemisorbed). These functional groups give it its unique properties and allow it to be incorporated into other materials in solution or in composites. Among its most important properties are its flexibility of use and transformation, as well as its ability to be reduced. According to INMA researcher Raúl Arenal, “In order to make use of its potential applications, this reduction is the critical point that needs to be well understood, which is not easy given the structural and chemical complexity of this material”.
Thus, the two recently published papers by the research group led by Arenal, have made it possible to study, on a local (sub-nanometric) scale, the reduction of graphene oxide through in-situ transmission electron microscopy (TEM) measurements. These thermal and Joule heating treatments have provided unique information on the behaviour, at different temperatures, of the different functional groups and water that make up this graphene oxide. Thanks to recently published research, it has been possible to observe and monitor how the reduction of this material is taking place and how its structure, chemical composition and electrical conduction properties are changing.
This work, which opens the door to the development of potential applications of graphene oxide, has been published in two renowned journals in the field of carbon-based materials, 2D Materials (IOP) and Carbon (Elsevier), where it has been featured on the cover of the June issue.
The studies have been carried out by the researchers: Raúl Arenal, ARAID researcher at INMA and LMA; Mario Peláez postdoctoral fellow at INMA and LMA, and Simon Hettler postdoctoral fellow at LMA, all belonging to the INMA research group “Nanoscopy on Low Dimensional Materials” (NLDM) led by Raúl Arenal. This work has been carried out in collaboration with Wolfgang Maser and Ana Benito from the Institute of Carbochemistry (CSIC).
Photo caption
Imagen 1: investigadores de izquierda a derecha: Simon Hettler, Raúl Arenal, Mario Peláez, Wolfgang Maser y Ana Benito.
Imagen 2: esquema ilustrativo de la reducción térmica del óxido de grafeno.
Simon Hettler, David Sebastian, Mario Peláez-Fernández, Ana M. Benito, Wolfgang K. Maser, Raúl Arenal: “In-situ reduction by Joule heating and measurement of electrical conductivity of graphene oxide in a transmission electron microscope”, 2D Materials 8, 031001 (2021). https://iopscience.iop.org/article/10.1088/2053-1583/abedc9
Mario Peláez-Fernández, Alba Bermejo-Solis, Ana M. Benito, Wolfgang K. Maser, Raúl Arenal: “Detailed thermal reduction analyses of Graphene Oxide via in-situ TEM/EELS studies”, Carbon 178, 477-487 (2021). https://doi.org/10.1016/j.carbon.2021.03.018
04/06/2021
