Enhanced Catalytic and Photocatalytic Degradation of Organic Pollutant Rhodamine-B by LaMnO3 Nanoparticles Synthesized by Non-Aqueous Sol-Gel Route

The water crisis is one of the major problem of the 21st century. This has led to the development of various techniques for water purification such as wastewater treatment. In this technique, coloring dyes are one of the most challenging materials to treat. Rhodamine-B (RhB) is one of the significant coloring agent and is very difficult to treat using conventional techniques. Here, the enhanced catalytic and photocatalytic degradation of RhB by LaMnO3 nanoparticles is reported. The sol-gel route is used for the synthesis of LaMnO3 nanoparticles, and structural, magnetic, optical and zeta potential studies are performed. X-ray diffraction analysis confirms the rhombohedral perovskite structure with R3c space group. The magnetic measurement at 5K shows that saturation magnetization value increases with an increase in particle size. UV-vis absorption study of LaMnO3 nanoparticles confirms the optical band gap decreases with increasing size. Zeta potential study of LaMnO3 nanoparticles shows a negative charge on the surface. Degradation of organic pollutant RhB by nanoparticles of LaMnO3 is performed under dark, followed by visible light irradiation. Under the dark, 90-92% of the RhB is degraded. Subsequently, upon visible light irradiation, it increased above 99%, confirming enhanced catalytic and photocatalytic activity of LaMnO3 nanoparticles over RhB.