Effect of zinc substitution for manganese on microstructural, optical and photocatalytic properties of LaMnO3 nanoparticles

Microstructural, optical, and photocatalytic properties of (x = 0, 0.05, 0.10, 0.15) LaMn1-xZnxO3 nanoparticles have been investigated by X-ray diffraction, Raman and Fourier transform infrared spectroscopy, field emission scanning electron microscope, Energy-dispersive X-ray spectroscopy, and UV-Vis spectroscopy. Our study indicates that there is a structural phase transition from the rhombohedral (space group R3c) to the orthorhombic (space group Pbnm I) structure. Lanthanum manganese (LM) is one of the most promising and efficient photocatalysts for the degradation of organic pollutants. To determine the photocatalytic performance of LaMn1-xZnxO3 nanoparticles, the effects of three operational parameters including irradiation time, pH, and the catalyst amount on the degradation of aqueous solution of methyl orange (MO) and methyl blue (MB) were investigated. The results showed that LaMn0.9Zn0.1O3 has higher photocatalytic activity than the LM for degradation of MO and MB under sunlight. A possible mechanism for better photocatalytic performance of the samples was discussed. The LaMn0.9Zn0.1O3 did not exhibit any significant loss after six cycles of the degradation of MO and MB under the same conditions.