Sol–Gel Synthesis and Characterizations of CoMoO<SUB>4</SUB> Nanoparticles: An Efficient Photocatalytic Degradation of 4-Chlorophenol

Cobalt molybdate CoMoO4 nanoparticles (NPs) were successfully synthesized using cobalt nitrate, ammonium molybdate, citric acid and ethyl cellulose by a simple sol-gel method. Structural, morphological, optical and magnetic properties of the obtained powder were characterized by powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectra, high resolution scanning electron microscope (HR-SEM), energy dispersive X-ray (EDX), UV-Visible diffuse reflectance spectra (DRS), photoluminescence (PL) spectra and vibrating sample magnetometer (VSM). XRD results indicated that the resultant powder was pure single phase crystalline with monoclinic structure. FT-IR spectra indicate the type of bonds between metals and oxygen. HR-SEM images shows that the morphology of the powder consist with well defined nanoparticles (NPs) structure. VSM results showed antiferromagnetic behavior. Photo-catalytic activity of CoMoO4 nanoparticles (NPs) was performed. The addition of TiO2 catalyst enhanced the photo-catalytic activity of CoMoO4 nanoparticles (NPs). The catalysts CoMoO4, Ti02 and mixed oxide catalyst CoMoO4-TiO2 nano- composites (NCs) were tested for the photo-catalytic degradation (PCD) of 4-chlorophenol (4-CP). It was found that the PCD efficiency of CoMoO4-TiO2 NCs was higher (97.5%) than that of pure CoMoO4 (88.0%) and TiO2 (94.0%) catalysts.