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In this work, compact titanitum dioxide (c-TiO2), amorphous titanitum dioxide (mp-TiO2) and methylammonium lead iodide (CH3NH3PbI3) films were prepared by spin coating method under different different rotational speed of the CH3NH3PbI3 films. Many characterization measurements were achieved on the deposited CH3NH3PbI3 films in order to study the change that resulted from different parameters. The X-ray diffraction (XRD) measurements revealed that the lattice constants of the fabricated CH3NH3PbI3 films were close to the slandered values. The atomic force microscopy (AFM) measurements were conducted in order to study the morphology of the fabricated CH3NH3PbI3 films at different scale, these results displayed that the grain size of the CH3NH3PbI3 films in the range between about 160nm to 210 nm. The field emiision scanning electron microscopy (FE-SEM) results of the fabricated CH3NH3PbI3 films were well agreed to the AFM result especially in the grains shape and distribution. Transmittance measurements have been done to determine the variation of the energy gap and absorption coefficient the CH3NH3PbI3 films. The structure form of the perovskite solar cells were FTO/c-TiO2/mp- TiO2/CH3NH3PbI3/Au, the C-V measurements were achieved to determine the built-in potential, which found to have the highest value when using 4000 rpm during the synthesis of the perovskite layer. In addition, the I-V measurements in dark conditions have been conducted to compute the ideality factor and the saturation current, which are considered important parameters that influences the characteristics of the solar cells. The best solar cell efficiency was obtained at spinning speed of 4000 rpm.

In this work, perovskite solar cells were fabricated with one-step method by using spin coating technique. These solar cells were in the structure form of FTO/compactTiO2/mesoporousTiO2/CH3NH3PbI3/Au. Different annealing temperatures were applied to investigate the effect of the annealing temperature on the properties of the fabricated solar cells since it lead to affect the crystallization degree of the CH3NH3PbI3 layer. Three temperatures were used for annealing the perovskite layer typically: 60°C, 80°C and 100°C and the best result found at 100 °C where the efficiency was 5.68%, FF = 0.55, Jsc = 12.637 mA/cm2 and Voc = 0.817 V.

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This search deals with the empirically obtained conditions for the fusion splicing with photonic crystal fibers (ESM-12) and (SMF-28) by controlling the arc-power and the arc-time of conventional electric-arc fusion splicer (FSM-60S). The development of microstructure fiber has been limited by the fact that these fibers are generally difficult, and in some cases even impossible, to fusion splice using conventional technologies. For this reason, fusion splicing microstructure fiber is an important area of research that is likely to impact the future direction of optical fiber technology . there are many kinds of fusion splicing techniques, enabling connection between two optical fibers, such as an electric arc and a CO 2 laser .It is likely that electric arc fusion splicing technique has been widely applied and even better established than the others, especially on the standard single mode fibers (SMFs).