LAUSR

Abstract In the present work, different morphologies of LaMnO3 nanostructures have been successfully synthesized by using a facile hydrothermal process with constant calcinations temperature. Sphere, rod and porous-like morphologies of LaMnO3 have been obtained by adding urea and cetyltrimethylammoniumbromide (CTAB) as a structure-directing agents. The surface morphologies and its growth parameters were analyzed by field emission scanning electron microscope (FESEM). Various analytical techniques were employed to analyze the phase purity, chemical structure, composition and band gap of the LaMnO3 nanoparticles. The photocatalytic activity of the different shaped LaMnO3 nanoparticles was assessed by the degradation of methylene violet (MV) dye in aqueous solution under sunlight irradiation. Among these, the porous-like LaMnO3 nanostructure provides the highest photocatalytic activity among the three morphologies with complete de-coloration of MV dye upto ∼95 % in 315 min. The specific surface area and pore volume of porous-like LaMnO3 nanostructure provides more active sites for the adsorption of MV dye. This result confirms porous like LaMnO3 plays a role in electron transfer and also provides an effective oxidative system to degrade MV dye. The photocatalytic degradation mechanism has also been discussed in detail.