Zinc oxide (ZnO) nanorods have been synthesized by solution processing hydrothermal method in low temperature using the spin coating technique. Zinc acetate dehydrate, Zinc nitrate hexahydrate and hexamethylenetetramine were used as a starting material. The ZnO seed layer was first deposited by spin coated of ethanol zinc acetate dehydrate solution on a glass substrate. ZnO nanorods were grown on the ZnO seed layer from zinc nitrate hexahydrate and hexamethylenetetramine solution, and their diameters, lengths were controlled by precursor concentration and development time. From UV-Visible spectrometry the optical band gap energy of ZnO nanorods was calculated to be 3.3 eV. The results of X-Ray Diffraction (XRD) showed the highly oriented nature of ZnO nanorods the hardest (002) peak reflects that c-axis elongated nanorods are oriented normal to the glass substrate. The Field Emission Scanning Electron Microscope (FESEM) was employed to measure both of average diameter of ZnO nanorods, Energy Dispersive X-Ray (EDX) is used to identify the elemental present and to determine the element composition in the samples.

The fabrication of planar Al/ZnO/Si heterojunction photodetectors has received considerable attention. The crystalline quality of ZnO plays an important role in the properties of the fabricated device. In this study, ZnO micro-rods were grown on Si (100) without any catalysts using atmospheric pressure chemical vapor deposition, and were characterized to determine their potential for application in highly photosensitive ZnO/Si photodetectors. The ZnO rods were grown with various diameters and had a wurtzite structure oriented in the (002) plane. The effect of the substrate temperature on the crystalline structure was studied in the range of 450-750°C. The planar structure of the Al/ZnO heterojunction photodetector indicated that the device is highly sensitive to ultraviolet and visible light. The photoresponse of the fabricated Al/ZnO device had a peak at 360 nm. The responsivity of the device reached 0.03 at a bias voltage of 1 V and reached 0.085 at a bias voltage of 5 V. The responsivity increased to 0.121 as the bias voltage increased to 10 V. The quantum efficiency of the device was 11, 32, and 42 % at bias voltages of 1, 5, and 10 V, respectively.

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Obtaining cheap Electronic Transparent Materials (ETM) and Hole Transparent Materials (HTM) is an important challenge for researchers in perovskite solar cells. we used the SCAPS software in order to determine the properties of CH3NH3SnI3-based solar cells with different ETM and HTM layers, such as (IGZO, SnO2, TiO2, ZnO) and (Spiro-OMeTAD, NiO, Cu2O, and CuO), respectively. Our results predict that among these ETMs, the SnO2 is the most promising to result in high photovoltaic (PV) efficiency in combination with Spiro-OMeTAD based HTM. In addition the perovskite absorber's thicknesses are optimized to achieve maximum photovoltaic efficiency. In order to increase efficiency, layer thickness in cell structures can be optimized by fixing the thickness of the first two layers while altering the thickness of the third. The perovskite solar cell's planar structure consists of ETM (SnO2)/perovskite absorber (CH3NH3SnI3) / HTM (Spiro-OMeTAD)/ and Gold (Au) as a back contact. Also, it improved the solar cell performance by optimizing the absorber thickness, which was 1 µm. With these considerations, the power conversion efficiency of 33.2698% is obtained. Also, we explore the effect of the defect at the perovskite/SnO2 interface on solar cell performance.

Laser hyperthermia treatment of cancer tissue is widely used in cancer treatment to destroy cancer cells. This study focus on the mechanisms of heat transfer in biological tissues to minimize damage to the tissues resulting from extra heat applied. The important feature of this method is heating of specific region to raise its temperature to a threshold temperature and destroying cancer cells without to destroy surrounding tissue. In this study, we have used the combinations of laser light and gold nanoparticles to investigate the influence of nanoparticles on the spatial distribution of temperature in the tumor and healthy tissues. Accurate simulations and solving Penne’s bio-heat transfer equation were used to solve and model the thermal tumor breast cancer in the presence of gold. Nanoparticles of some particular sizes and concentrations were selected. We would like here to stress that our attempt was a theoretical and computer model with some real and hypothesized parameters and homogeneous target. The results of this study help the doctors in the study for results of hyperthermia treatment before using it on the vivo by known the properties of the laser used and the properties of the breast tumor trying to reduce the damage of the treatment.

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