However, for elemental composition and texture analysis one has to resort to scanning probe microscopy and scanning electron microscopy. However, the lower cost of XRD makes it the preferred choice for studies directed towards evaluation of fine grain minerals and mixtures or intergrowths at the microscopic level. XRD Analysis complements information obtained from other analytical techniques such as polarized light microscopy and scanning electron microscopy. In addition x-ray diffraction provides details on degree of crystallinity, amorphous content, grain size, lattice deformations due to strain and can help trace the origins of minerals. The diffraction pattern can be matched with a library of over 17,000 patterns for different minerals offered by the International Centre for Diffraction Data (ICDD).Using the data base helps in both qualitative and quantitative estimation of minerals. Each mineral generates its unique x-ray diffraction pattern which serves to identify it. Minerals are inorganic materials majority of which exhibit a degree of crystallinity. Mining is an applied science which concerns with extraction of ores, fossil fuels for energy needs and minerals for commercial processing. Geology is the scientific study on structure of planet earth, formation of rocks, sediments and minerals. X-ray diffraction or XRD has made valuable contributions in the field of geology and mining. Higher than 1.2 wt% Cu loading gave less rate of methanol yield because of the masking effect of Cu 2 O clusters on the surface of TiO 2. hr using 1.2 wt%-Cu/TiO 2 catalyst under 16 W/cm 2 irradiation, 1.3 bar pressure of CO 2, and 5000 seconds mean residence time.Maximum methanol rate was 0.45 µmole/g-cat Photo activity increased with increasing Cu loadings. The methanol yield increased with UV irradiative intensity. Most active Cu species on TiO 2 surface were Cu 2 O clusters, and played an important role for the formation of methanol. The wavelength of absorption edge was on 367 nm, equivalent to near 3.3 eV. 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. 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.
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