The effect of shape and size of 1D and 0D titanium oxide nanorods in the photocatalytic degradation of red amaranth toxic dye

Abstract In this work, the effect of layered TiO2 anatase nanorod preparation and application were systematically analyzed. The nanoparticles were widely characterized and applied in the photocatalytic degradation of red amaranth toxic dye. The nanorod morphology changed with the type of acid treatment; they decreased in length and diameter with the increase in acid concentration. The use of HCl induced a preferential growth of (101) planes, while HNO3 favored the formation of the (004) face. Likewise, the HCl acid treatment allowed the incorporation of small quantities of Cl − ions on the surface of TiO2 anatase, impacting the activity positively. Otherwise, the presence of surface nitrogen was not detected when treated with nitric acid. The characterization and activity result allowed us to propose structure–activity correlations with morphology and Cl − ions. It was revealed that the Na removal enhanced reactivity revealing to the enhanced crystallinity of TiO2 nanorods is responsible for the photocatalytic activity results. We conclude that these nanomaterials are suitable as catalysts for the degradation of dye pollutants in water if a fine-tuning is done with acid solutions.