A comparative analysis on the dye degradation efficiency of pure, Co, Ni and Mn-doped CuO nanoparticles

Pure, Co, Mn and Ni (1.0 wt%) doped CuO Nanoparticles (NPs) are synthesized by co-precipitation method for the catalytic property analysis. The powder X-ray diffraction pattern of pure, Co, Mn and Ni doped CuO NPs shows that the Co²⁺, Mn²⁺ and Ni²⁺ ions are successfully substituted to Cu²⁺ ion. Fourier transform infrared spectroscopy studies confirms the functional groups present in the synthesized samples. The band gap of pure CuO NPs is increased from 3.230 to 3.256 eV and 3.274 eV by adding the dopants Co and Ni. Whereas, the addition of Mn decreases the band gap to 3.207 eV. Scanning electron microscopy images show the considerable change in morphology from the nonuniform surface of nanostructure to nano flakes when Co, Mn and Ni are added as dopants. From photoluminescence spectrum, the broad green emission is observed at 521 nm. The electrical properties of synthesized materials are studied and compared by dielectric constant, dielectric loss and ac conductivity measurements. The electrochemical impedance properties of the prepared samples were also investigated. The degradation of environmental pollutants such as 4-Nitrophenol and Methylene blue dyes are analyzed by studying the catalytic activity of the synthesized material and reported.