Ilnaz Abdolmaleki - Department of Science, Payame Noor University (PNU), PO Box ۱۹۳۹۵-۴۶۹۷, Tehran, Iran

Spinel is a cubic structure with the public formula AB۲O۴, that A and B are cations settled in thetetrahedral and octahedral positions, respectively. therefore, a spinel has ۵۶ atoms in any onecell. The dispensation of ions in A and B sites are subject to the ion equilibrium [۱]. Materialsand it Nanotechnology is an interdisciplinary knowledge, it is the interdisciplinary, includingtoxicology, medical, physics, chemistry, biology, mechanics, engineering, and recentlyenvironment [۲]. in the last decade, environmental pollution has enhancement more and morepublic worry. for example, wastewater including dyes arriving from paper, textiles, plastic andleather industries is usually high in organic compounds and color [۳]. This pollutant agent createimportant environmental problems. So, providing effective and efficient method for theirremoval from wastewater is necessary. Photocatalysis is one of this efficient approach to removethe dyes from wastewater [۴]. Among the pollutant agent, we can point to organic dyes fromindustrial processes and textile as one of the main polluting water sources and create animportant environmental crisis. Photocatalysis is considered as one of the important and efficientapproaches to dismiss the dyes in wastewater [۵]. In this paper a novel and inexpensive route forthe preparation of spinel CoCrMnO۴ nanoparticles is proposed and Congo red was used asmodel dye. The obtained nanoparticles were then identified using different analytical techniquessuch as Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), andfield emission scanning electron microscopy (FESEM). The X-ray powder diffraction (XRD)confirmed the formation of cubic spinel phase CoCrMnO۴. The photocatalytic activity ofCoCrMnO۴ nanoparticles were studied by performing the decomposition of Congo red dye undervisible light irradiation. The effects of process parameters like, catalyst dosage, initial dyeconcentration, and visible light irradiation on dye degradation have been investigated.