Removal and photodegradation of methylene blue on the surface of three distinct carbonaceous materials, pure and nitrogen-doped multi-walled carbon nanotubes, and graphitic nanoribbons, were examined. Carbon nanostructures were characterized by scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, Raman spectroscopy, X-ray photoelectron spectroscopy, and N2 adsorption/desorption isotherms. Removal and photocatalytic activity were evaluated by static adsorption under UV irradiation. Photocatalytic activity on carbon nanostructure exhibited a pseudo-first-order kinetic model. The adsorption capacity and photocatalytic activity of carbon nanostructures were mainly attributed to their defective and reactive surface. Nitrogen-doped multi-walled carbon nanotubes showed the best adsorption capacity and photocatalytic activity, which can be attributed to the highly reactive sites due to nitrogen doping, also by π–π electron donor-acceptor interaction between sp2 lattice of carbon nanostructure surface and negatively charged sites at methylene blue molecules. Display omitted •Carbon nanotubes and nanoribbons were used to adsorb and photo-degradation of methylene blue.•N-doped nanotubes showed higher photocatalytic degradation of methylene blue than pure carbons.•Carbonaceous materials removed methylene blue by two mechanisms, adsorption and photocatalysis.•The photocatalytic degradation of dye occurred by the reaction with OH, O2−, and HO2.