Síntesis y caracterización de puntos cuánticos de grafeno : obtención de GQDs mediante síntesis hidroterma.

Abstract

The current study delves into the synthesis and characterization of graphene quantum dots, starting from the graphene acquisition. Materials derived from graphene have demonstrated significant value in various sectors, including medicine, pharmaceuticals, sensors, and other fields of interest. As a result, the synthesis of these materials has garnered attention from numerous researchers. In this context, multi-layer graphene was initially obtained through the method of mechanical exfoliation in a liquid medium using a lysis equipment, yielding of 80.3 %. Chemical and morphological analyses confirmed the effectiveness and scalability of this technique. Subsequently, graphene oxide was synthesied through the modified Hummers method. Characterization processes verified the oxidation of graphene by identifying the C=O bond. Lastly, the hydrothermal method was employed to derive GQDs from the previously synthesized graphene oxide. In this process, reagents were introduced to facilitate the production of GQDs doped with both nitrogen and sulfur in their structure. Chemical characterization of the GQDs revealed that those obtained using ammonia as a reagent achieved nitrogen doping. Conversely, GQDs obtained with thiourea as a reagent showed no evidence of sulfur doping. This outcome implies that the employed procedure, encompassing the combination of mechanical exfoliation in a liquid medium, the modified Hummers method, and the hydrothermal method with thiourea as a reagent, is not conducive to producing sulfur-doped GQDs. Nevertheless, it proves effective for nitrogen doping when ammonia is utilized as a reagent.