The XRD spectra indicated the anatase phase of all TiO 2 and Cu/TiO 2 films. The thickness of Cu/TiO 2 film was 53 nm and consisted of very fine spherical particle with diameter of near 14 nm. Titania and Cu-loaded solutions were prepared by a thermal hydrolysis method. TiO 2 film was coated on optical fiber using dip-coating method. The optical-fiber photo reactor, comprised of near 120 Cu/TiO 2-coated fibers, was designed and assembled to transmit and spread light uniformly inside reactor. In our study, CO 2 was photocatalytically reduced to produce methanol using a Hg lamp with wavelength 365 nm in a steady-state optical-fiber photo reactor. One of the best routes to remedy CO 2 is to transform it to hydrocarbons using photo reduction. Alternative energy source should be provided without producing more CO 2, such as solar energy. Greenhouse gas such as CO 2 is the primary cause of global warming. Moreover, in this work, both the valence and conduction band edge positions are found to shift negatively with increasing Cu deficiency in these films. This leads the optical and transport gap to increase from 1.36 eV to 2.23 eV and 1.31 eV to 2.02 eV respectively with increasing copper deficiencies from Cu2S to CuS. This is because of the induced Cu deficiency in Cu2-xS films with decreasing Cu/S-molar ratio, which reduced the Cu d-band width in the valence band, thus pushing the Fermi level deep into the valence band. The hole concentration of these films are found to vary from 3.32 × 1019 cm−3 to 2.54 × 1022 cm−3 as Cu2-xS composition changes from Cu2S to CuS. To this end, varying composition of Cu2-xS (i.e., Cu2S, Cu1.96S, Cu1.8S, Cu1.8S+ Cu1.6S and CuS) films were grown here by using a low temperature molecular solution based deposition method, following which a wide range of characterization tools were used to understand their microstructure, electronic structure and optoelectronic properties. « lessĬopper- and silver-zirconia aerogels containing 10 at% IB metal were prepared from tetra-n-butoxy zirconium(IV) and IB metal acetates using the solution sol-gel method and ensuring high-temperature (HT) and low-temperature (LT) supercritical drying, respectively.Copper sulfide (Cu2-xS) is a class of low-cost, environment friendly p-type semiconductor, where electronic structure and the thus induced optoelectronic properties can be significantly varied through the creation of copper deficiency. The optical bandgap decreases with increasing x, which is due to the emergence of Cu-d states at Fermi-level near the valence bands, thus making Cu-doped zirconia a hole doped (p-type) semiconductor. This magnetic analysis confirms the findings from x-ray diffraction that only a part of Cu is successfully doped into cubic phase of Cu-doped ZrO 2. The temperature dependence of magnetic susceptibility measurements from 2 K to 300 K exhibits Curie–Weiss behaviour whose analysis using g a = 2.1 and spin S = 1/2 yields x = 0.028 and x = 0.068 for the nominal x = 0.05 and x = 0.20 samples, respectively. Electron magnetic resonance studies provide evidence for the substitution of Cu 2+ ( 2D 5/9,3d 9) ions at Zr 4+ sites with g ∥ = 2.250, g ⊥ = 2.018 and average g a = (g ∥ + 2g ⊥)/3 ~ 2.1. At x = 0.05 and 500 ☌ calcination temperature, we observe a high degree of cubic crystallinity which breaks down into monoclinic phase with increasing calcination temperature beyond 550 ☌. For $$x x_c$$, the monoclinic CuO emerges as a secondary phase with shrinkage of unit-cell volume with increasing the Cu content. Thermal analysis and kinetics of crystallization revealed that the cubic phase at ambient temperature can be stabilized by using a critical calcination temperature of 500 ☌ for 8 h in air and a critical composition of $$x_c$$ = 0.10 ± 0.05. Various compositions of Zr 1– xCu xO 2 (0.01 ≤ x ≤ 0.25) nanocrystallites of average size ~16 nm were synthesized using co-precipitation technique. « lessīy means of experimental and ab initio investigations, in this article we report on the cubic phase stability of Cu doped zirconia (ZrO 2) at room temperature, and further characterize its structural, optical and magnetic properties. Recently, highly active CO solid solution phase.
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