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In this article, a low cost chemical bath deposition (CBD) technique has been used for the preparation of Cu_2-xSe thin films on to glass substrate. Different thin films (0.2–0.6 μm) were prepared by adjusting the bath parameter like concentration of ammonia, deposition time, temperature of the solution, and the ratios of the mixing composition between copper and selenium in the reaction bath. From these studies, it reveals that at low concentration of ammonia or TEA, the terminal thicknesses of the films are less, which gradually increases with the increase of concentrations and then drop down at still higher concentrations. It has been found that complexing the Cu²⁺ ions with TEA first, and then addition of ammonia yields better results than the reverse process. The film thickness increases with the decrease of value x of Cu_2-xSe.

In the field of semiconductor nanooptics, copper chalcogenides have challenged a novel direction associated with nontrivial optical features in the near IR range important for applications. We consider this phenomenon in the silica sol–gel derived glasses doped with copper selenide nanoparticles. They were characterized with transmission electron microscopy, X-ray photoelectron spectroscopy and optical absorption spectroscopy. An origin of the near IR optical features is discussed involving both the plasmon resonance concept extended to the self-doping of chalcogenides with a variable stoichiometry and the effect of Cu²⁺ impurity-generated intraband levels providing linear and nonlinear optical response of these materials.

Cu₂Se nanowires with diameters of about 25 nm and several hundred nm in length were synthesized at room temperature using a Se²⁻ solution prepared by microwave-assisted method. The influencing factors to product morphologies were investigated on the basis of series of control experiments. The as-synthesized products were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The optical properties were studied by means of UV-Vis absorption spectroscopy and photoluminescence (PL) spectrum. The results show that the direct band gap energy of the Cu₂Se nanowires is 2.02 eV. Copper sources, molar ratio of Cu/Se element, microwave and reducing agent significantly influence the morphology of the final products. Thus, product morphologies are controllable by simply regulating reaction conditions.