Nickel Doped Mn304 Nanoparticles: Synthesis, Characterization and Application as Photocatalyst

Abstract

In the present research work, pristine and (1 -4) % weighted percentage of Ni doped Mm04 nanoparticles were successfully synthesized followed by a co precipitation method and characterized with UV-Visible spectroscopy, X-Ray powder diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR). UV-Visible spectroscopy was performed to find the optical properties of synthesized materials. It indicated that with an increase in Nickel percentage ranging from 1 to 3 % weighted percentage, a red shift was observed and with further increase in dopant percentage to 4 % weighted percentage, a decrease in wavelength was observed. Tauc plots of the synthesized nanoparticles showed tuning in band gap from 2.50 to 2.37 eV. XRD was done to check the purity and crystallinity of the materials. We found the average crystallite size through XRD technique. This analysis showed that the average crystallite size increases with increasing dopant percentage up to 3 % weighted percentage ofNi. For 4 % weighted percentage ofNi, a decrease was calculated. FT IR was done for the functional group detection and vibrational study of synthesized materials. This study confirmed that the prepared samples were pure and showed vibrational bands of required samples. The application of synthesized nanoparticles was studied by using them as a catalyst for the degradation of dyes which are Methyl blue dye and Methyl orange dye. To find optimal conditions for both dyes, different parameters were checked which include percentage of dopant, dosage of catalyst, dye concentration and study of pH. Among all the catalysts, 3 mg dosage of 4 % Ni-Mll304 NPs showed maximum photo degradation efficiency (%PDE). 95.3 % of Methyl blue dye was degraded in 75 minutes at a basic pH 11 for 30 flM concentration of Methyl blue dye solution. Hence, Methyl blue was degraded by adsorbing it on the surface of prepared catalysts. The optimal conditions for 80 flM concentration of Methyl orange dye solution were found to be 2 mg amount of 2 % Ni-Mm04 NPs. 90 % of Methyl orange dye was degraded in 90 minutes under the optimal conditions. In order to remove organic pollutants from wastewater, photocatalysis is the most appealing and environment friendly chemical method. In this entire work, optimal conditions were found for the photocatalytic degradation of dyes in the presence of sunlight.