Abstract:

A series of CuO–K₂Mo₄O₁₃ composite materials have been prepared by mixing appropriates quantities, in solid state, of CuO and pure K₂Mo₄O₁₃ according to the molar ratios CuO/K₂Mo₄O₁₃ = 0.05, 0.1, 0.2, 0.5, and 1. The prepared samples were characterized using techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), differential thermal analysis (DTA), nitrogen adsorption measurements, and UV spectroscopy. According to XRD results, the phase composition of the CuO–K₂Mo₄O₁₃ systems has significantly changed by increasing the molar ratio CuO/K₂Mo₄O₁₃ where new phases, identified as K₂Mo₃O₁₀ and CuMoO₄, have been detected. The formation of these new phases has been tracked through FT-IR and DTA measurements. The nitrogen adsorption–desorption measurements also reveal a change in the pore type of the studied materials due to the presence of these new phases. The photocatalytic activities of K₂Mo₄O₁₃ and CuO–K₂Mo₄O₁₃ composites were studied by means of monitoring the ability of these materials to the degradation, under UV irradiation, of methyl red in liquid media. It was found that the phase composition of the used samples significantly controls their photocatalytic activities.

Key words: Potassium tetramolybdate, Copper oxide, Composite, Photocatalyst