Carbon-based nanocompositesNanocomposites (CNCs) have great potential for various environmental applications due to their unique physical and chemical properties. These nanomaterials are widely used in the chemical industry as catalysts or catalyst supports in energy and ecological applications. Key properties like high surface areas, porosity, sizes, and shapes increase the catalytic performance of carbon-based materials. GrapheneGraphene and carbon nanotube-based NCs have shown exceptional catalytic activity in organic reactions. Catalytic products prepared using CNCs have significant importance in fields like medicine, biomedicalBiomedical, agricultural, and material sciences. As a result, the demand for CNCs is growing rapidly. Developing new preparation methods and expanding application areas make this field special. The unique hybridization properties of CNCs allow for tailored manipulation of their structures and morphologies. However, pristine carbon materials typically have unsatisfactory photocatalytic performances and practical applications due to light absorption and the rapid recombination of photogenerated electron–hole pairs. The main challenge is designing economical, environmentally friendly, and effective photocatalysts. Combining carbonaceous materials with carbonaceous semiconductors of different structures results in unique properties in carbon-based catalysts, offering a promising approach to achieving efficient applications. This chapter aims to contribute to the catalytic removal of organic pollutants from wastewater by catalyzing photocatalytic processes. It provides a direction for empowering improvements in ongoing research work, boosting future applications, and contributing to overcoming existing limitations in this field.