CuO as efficient photo catalyst for photocatalytic decoloration of wastewater containing Azo dyes

摘要

Cupric oxide nanoparticles (CuO NPs) were prepared via a chemical precipitation method using the precursor of copper (II) nitrate trihydrate. X-ray diffraction analysis confirms that the CuO NPs were monoclinic crystal structure. The energy band gap of CuO NPs was found to be about 1.76 eV. The obtained CuO NPs were used as a photo catalyst to decolorize various dyes, such as methylene blue (MB), acid yellow 23 (AY 23) and reactive black 5 (RB 5), with a low concentration in the presence of visible light. The results show that the highest decolorization achieved was 67.8% and 66.3% for RB-5 dye and AY-23 dye, while 43.5% for MB dye from aqueous solution at 5 h illumination. The obtained CuO NPs were used as a photo catalyst to decolorize various dyes, RB-5, AY-23 and MB dye obeys pseudo first order kinetics with values of -0.112, -0.174 and -0.201 h(-1), respectively.