Characterization of graphene oxide obtained from modifications of hummers’ method and its application for reinforcing textiles
- Autores: Jordi Aixart Forés
- Directores de la Tesis: Francesc Díaz i González (dir. tes.), Joan Rosell Llompart (codir. tes.)
- Lectura: En la Universitat Rovira i Virgili ( España ) en 2021
- Idioma: español
- Tribunal Calificador de la Tesis: Francesc Medina Cabello (presid.), Josep Maria Serres Serres (secret.), Vicente Muñoz-Sanjosé (voc.)
- Programa de doctorado: Programa de Doctorado en Nanociencia, Materiales e Ingeniería Química por la Universidad Rovira i Virgili
- Materias:
- Enlaces
- Tesis en acceso abierto en: TDX
- Resumen
Graphene Oxide (GO) is a novel nanomaterial related to the well-known graphene. It is often obtained from the chemical oxidation of graphite and consists in graphene layers with different oxygen functionalities. Its popularity lies in the ease of production, scalability, and affinity with water, which facilitates its handling and application. It can be partially reconverted to graphene via chemical reduction, or it can be used as a material itself, as its oxygen functionalities have huge potential in numerous applications.
The most widely used reaction for the obtention of GO is the Hummers method, where graphite is oxidized using strong oxidants in acid media. The result is an aqueous dispersion of GO flakes which contain chemical richness consisting in different functional groups, mainly epoxides, hydroxyls, carbonyls, carboxyls and organosulfates.
GO is a delicate nanomaterial whose chemistry and morphology of the flakes strongly depends on the Hummers’ reaction parameters. Surprisingly, it is common to see studies where GO is used in an application without much description of its preparation. This has led to numerous studies about application of GO but also to a clear need for fundamental research on the preparation and characterization of GO.
In this thesis, fundamental studies have been made about Hummers’ method and the morphological and chemical characteristics of the GO flakes. Different GOs have been obtained by modifications of reaction time and temperature in Hummers’ method. The obtained GOs have been characterized and their different morphological and chemical properties have been described and interpreted. Subsequently, the same GOs were subjected to intense purification procedures and exfoliation observing that these procedures, commonly used in the literature, have an important effect on the characteristics of the GOs, causing shattering of the GO flakes into smaller pieces while reducing the chemical richness of the GOs relative to their state prior to the treatments. With our modifications of the Hummers method, GOs with tailorable morphology and chemistry have been obtained.
Finally, this thesis project has been made possible thanks to an industrial R&D collaboration with a technical-textiles company. Some of the main results are, therefore, also described. GO has been applied to textiles to improve their mechanical strength. The large-scale production and application of GO to textiles has been demonstrated using industrial equipment at pilot scale, obtaining fabrics coated with GO with about 50% improved mechanical resistance to puncture.
