"Sunlight-driven catalytic degradation of MB dye and multi-cycle Re-usability analysis of CuSe nanoparticles".

One of the best ways to remove organic dyes based contaminant from water resources and industrial waste water is the sunlight driven photo-catalytic degradation method. The theme of the present investigation is the photocatalytic degradation of methylene blue (MB) dye using economically produced CuSe nanoparticles (NPs) catalyst under solar radiations. The CuSe NPs crystallized in the cubic structural phase with an average crystallite size around 19 nm. The direct band gap was found to be 2.1 eV. The PL spectra and corresponding CIE diagram show the CuSe NPs emitted yellow color. The SEM micrographs show that the small grains staked over others to form large grains or patches. The FTIR and EDX spectra confirmed the formation of CuSe NPs. The obtained optimum photocatalytic degradation efficiency for CuSe NPs is 90.3 %. For first cycle analysis. The pseudo-first order and second order models were used to analyze the kinetic data of CuSe NPs for varying concentrations. The multiple-cycle degradation analysis by catalyst of MB dye in one day spam for continuous four cycles were also analysed and discussed. The sun light driven multi-cycle catalytic degradation confirms the re-usability of CuSe NPs for the treatment of industrial waste water and other contaminated water bodies for the survival of aquatic life and for saving environment.