Adsorption and photocatalytic study of dyes for waste-water treatment using Mn modified DyCrO 3 nanomaterials

In the present work, DyCr 0.8 Mn 0.2 O 3 and DyCr 0.5 Mn 0.5 O 3 nanoparticles have been prepared via the sol-gel route and characterized by X-ray diffraction and UV-Visible Diffuse reflectance spectroscopy, SEM, EDX, and Photoluminescence spectroscopy. The influence of Mn substitution on the structural, optical, and photocatalytic properties of DyCrO 3 has been studied. The XRD patterns confirm the orthorhombic phase of compounds with Pbnm space group. Furthermore, crystallite size of the nanoparticles is found to be 79.36 nm and 83.33 nm for DyCr 0.8 Mn 0.2 O 3 and DyCr 0.5 Mn 0.5 O 3 , respectively. The optical bandgap energy of DyCr 0.8 Mn 0.2 O 3 and DyCr 0.5 Mn 0.5 O 3 compounds is 2.68 eV and 2.34 eV, respectively. The Photoluminescence spectrum exhibits blue, yellow and red emissions at 380 nm excitation wavelength. The dye degradation efficiency of DyCr 0.8 Mn 0.2 O 3 and DyCr 0.5 Mn 0.5 O 3 compounds was tested on MB and RhB dyes under solar light irradiation for 180 min. The highest degradation efficiencies for DyCr 0.8 Mn 0.2 O 3 and DyCr 0.5 Mn 0.5 O 3 compounds are 84% and 92% for RhB dye and 63% and 77% for MB dye in the presence of solar irradiation. The photodegradation kinetics obeys the first order linear kinetics and adsorption data follows pseudo second order model. Further, adsorption isotherms process follows the Langmuir and Freundlich model in the dark. Graphical Abstract Absorbance spectra of RhB dye using DCMO20 and DCMO50 photocatalysts under solar light irradiation