Saman Rahnamaeiyan - Young Researchers and Elite Club, borujerd branch, Islamic Azad University, borujerd, Iran
Mahdi Nasiri - Young Researchers and Elite Club, borujerd branch, Islamic Azad University, borujerd, Iran
Ruhollah Talebi - Young Researchers and Elite Club, Central Tehran Branch, Islamic Azad University, Tehran, Iran
Saeid Khademolhoseini - Young Researchers and Elite Club, South Tehran Branch, Islamic Azad University, Tehran,Iran

Pure cobalt aluminate (CoAl2O4) nanoparticles were successfully synthesized by novel sol-gel method with the aid of Co(NO3)2•3H2O, Al(NO3)3•9H2O, and gelatin without adding external surfactant or template. Besides, the effect of the dosage of gelatin on the particle size of final product was investigated. Moreover, gelatin plays role as capping agent, reducing agent, and chelate agent in the synthesis CoAl2O4 nanoparticles. The cobalt aluminate nanoparticles were characterized by using X-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet–visible (UV–vis), Fourier transform infrared spectroscopy (FT-IR), and spectra energy dispersive analysis of X-ray (EDS) techniques. To evaluate the catalytic properties of nanocrystalline cobalt aluminate, the photocatalytic degradation of methyl orange (MO) under visible light irradiation was carried out.

CoAl2O4; Nanoparticles; Novel sol-gel; Semiconductor; Photocatalyst