In this article, the effects of the O2 ratio  on the electrical characteristics, including the I-V characteristic curve, Panchen’s curve, and I-P curve, were tested in a sample of O2/Ar gaseous mixture . The sample was produced by plasma-based DC magnetron sputtering with niobium metal as a target material. The inter-electrode spacing value was 4 cm. Plasma diagnosis via the Optical Emission Spectroscopy (OES) method was used to achieve Te and Ne mixture values of 20 %, 30 %, 50%, and 70% in the Ar/O2 system. The results showed that the discharge is operating in the abnormal glow region and the discharge current was decreased by increasing O2 percentage. In addition, the experimental results showed that the discharge is optimal at 30% gas ratio.  It was found that the electron temperature was decreased with increasing working pressure and increased with increasing the O2 percentage, while electron density was increased with increasing both working gas pressure and O2 percentage.

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The optoelectronic properties of dye zinc and titanium-based metal-organic framework (MOF) compounds with regard to their application as photo-anode material characterized in solar cells were investigated. Analyses of the optoelectronic properties were performed on the MOF single crystal unit cell with adsorbed dye to determine the electronic and optical properties of the relevant materials. The electronic and optical properties were predicted by density functional theory (DFT) calculations. The results show that the absorption of light occurs for the examined MoF compounds from the near UV to the (visible) blue spectral range, at optical band gap sizes from 2.8 eV up to 3.88 eV. Dye sensitization of MOF with eosin Y or crown ether gave additive UV-Vis spectra. An improvement in band gap or an improved electron injection could be archived as well. Moreover, the light absorption does not solely depend on the linkers used, but also from the metal atoms in the secondary building unit. The fluorescence of MOFs depends on the linker and especially on the linker coordination and their rotation relative to each other. The utilizations of MOFs and their derivatives as electrodes, photoactive materials, charge carriers and additives in different solar cells are highlighted.

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