Abstract: Research on carbon-based photocatalytic nanomaterials has been a field in continuous expansion in the last years. Graphene (or its derivatives) is currently one of the most studied materials due to its high surface area, photodegradation resistance, optical transparency and high charge mobility values. All of these excellent properties are highlighted for applications in various research areas. The incorporation of small amounts of reduced graphene oxide (RGO) sheets in semiconductors matrices is also a strategy widely used to improve the physicochemical properties, which cannot normally be achieved using conventional composites or pristine semiconductors. Most studies suggest that these twodimensional (2D) materials can facilitate electron injection and assist the electron transport in semiconductors. In this context, this manuscript will present examples of graphene-based semiconductor nanocomposites obtained by our research group and their application in the photodegradation of methylene blue (MB), photocatalytic conversion of CO2 to hydrocarbon fuels and photocatalytic water splitting reaction. Our results show the positive effect of coupling the RGO sheets with semiconductors for photocatalysis Ver menos