Aluminum doped zinc selenide ZnSe/n-Si thin films of (250∓20 nm) thickness with (0.01, 0.02 and 0.03), are depositing on the two type of substrate (glass and n-Si) to manufacture (ZnSe/n-Si) solar cell through using thermal vacuum evaporation procedure. physical and optoelectronic properties were examined for the samples. X-Ray and AFM techniques are using to study the structure properties. The energy band gap of as-deposited ZnSe thin films for changed dopant ratio were ranging from (2.6-2.68 eV). The results of Hall effect show that pure and doping films were (p-type), and the concentration carriers and the carriers mobility increases with increase Al-dopant ratio. The (C-V) have shown that the heterojunction were of abrupt type. In addition, the I-V characteristics of ZnSe /Si heterojunctions show the forward dark current varies with applied voltage, besides the saturation current and the ideality factor are determined under different doping percentage. Also, the (I– V) characteristic for ZnSe/Si heterojunction show that the forward current at dark varies with applied voltage and the Isc and Voc have been studied. The photoelectric properties designated an increase light current of hetero junctions with cumulative Al-dopant, and I-V characteristics under illumination showed that the heterojunction (ZnSe: Al (0. 3%)/Si) have a high efficiency.
Solar cells thin films were prepared using polyvinyl alcohol (PVA) as a thin film, with extract of natural pigment from local flower. A concentration of 0.1g/ml of polyvinyl alcohol solution in water was prepared for four samples, with various concentrations of plant pigment (0, 15, 25 and 50) % added to each of the four solutions separately for preparing (PVA with low concentrated dye , PVA with medium concentrated dye and PVA with high concentrated dye ) thin films respectively . Ultraviolet absorption regions were obtained by computerized UV-Visible (CECIL 2700). Optical properties including (absorbance, reflectance, absorption coefficient, energy gap and dielectric constant) via UV- Vis were tested, too. Fourier transform infra
... Show MoreThis research aims to investigate the effect of four types of nanomaterial on the Marshall properties and durability of warm mix asphalt (WMA). These types are; nano silica(NS), nano carbonate calcium (NCC), nano clay(NC), and nanoplatelets (NP). For each type of Nanomaterial, three contents are tried as following; NS(1%, 3%, and 5%), NCC(2%, 4%, and 6%), NC(3%, 5%, and 7%), and NP (2%, 4%, and 6%) by weight of asphalt cement. Following Marhsall mix design method, the optimum asphalt cement content is determined, thereafter the optimum dosage for each nanomaterial is obtained based on the highest Marshall stability value. The durability of the control mix (no nanomaterial) and modified mixtures have been compared based on moisture damage, r
... Show MoreThe compounding of polyvinyl chloride (PVC) with two types of fillers and some additives were studied for the manufacturing of acid resistant tile. Various concentrations of two types of fillers namely; calcium carbonate and recycled glass powder were used along with different additives generally categorized as plasticizers, stabilizers, and lubricants were mixed in the standard concentration unit parts per hundred resins (phr) with the PVC as base polymer. The effects of filler materials on acid resistant towered different acids like sulphuric, nitric and hydrochloric at different concentration were studied. Samples which passed the test were further checked for dielectric strength and mechanical properties. It was found that the recycl
... Show MoreThe physical, the thermal and the mechanical properties of Nano-composites, that consisted of Polyprime EP epoxy that reinforced by multi-walled carbon nanotubes (MWCNTs), have been studied. Various loading ratios, 0.1, 0.5, and 1 wt. %of MWCNT shave been infused into epoxy by a magnetic stirrer and then the hardener mixed with the mthat supplied with the epoxy. All sample shave been cutting using CNC machine. Tensile test, three-point bending, hardness tests, lee's disk, differential scanning calorimetry, water absorption and dielectric and electrical conductivity test were utilized on unfilled, MWCNT-filled epoxy to identify the loading effect on the properties of materials. Scanning electron microscopy (SEM) was used to determine the
... Show MoreThe electrical properties of Poly (ethylene oxide)-MnCl2 Composites were studied by using the impedance technique. The study was carried out as a function of frequency in the range from 10 Hz to 13 MHz and MnCl2 salt concentration ranged from 0% to 20% by weight. It was found that the dielectric constants and the dielectric loss of the prepared films increase with the increase of the MnCl2 concentration; The A.C. conductivity increases with the increase of the applied frequency, and the MnCl2 content in the composite membrane. Relaxation processes were observed to take place for composites which have a high salt concentration. The observed relaxation and polarization effects of the composite are mainly attributed to the dielectric
... Show MorePolymer blended electrolytes of various concentrations of undoped PAN/PMMA (80/20, 75/25, 70/30, 65/35 and 60/40 wt%) and doped with lithium salts (LiCl, Li2SO4H2O, LiNO3, Li2CO3) at 20% wt have been prepared by the solution casting method using dimethylformamide as a solvent. The electrical conductivity has been carried out using an LCR meter. The results showed that the highest ionic conductivity was 2.80x10-7 (Ω.cm)-1 and 1.05x10-1 (Ω.cm)-1 at 100 kHz frequency at room temperature for undoped (60% PAN + 40% PMMA) and (80% PAN + 20% PMMA) doped with 20%wt Li2CO3 composite blends, respect
... Show MoreIn this work, nanostructure porous silicon surface was prepared using electrochemical etching method under different current densities. I have studied the surface morphology and photoluminescence (PL) of three samples prepared at current densities 20, 30 and 40 mA/cm2 at fixed etching time 10 min. The atomic force microscopy (AFM) images of porous silicon showed that the nanocrystalline silicon pillars and voids over the entire surface has irregular and randomly distributed. Photoluminescence study showed that the emission peaks centered at approximately (600 – 612nm) corresponding energies (2.06 – 2.02eV).
While current-voltage characteristics shows, as the current density increase the current flow in the forward bias is decreasi
The solution casting method was used to prepare a polyvinylpyrrolidone (PVP)/Multi-walled carbon nanotubes (MWCNTs) nanocomposite with Graphene (Gr). Field Effect Scanning Electron Microscope (FESEM) and Fourier Transformer Infrared (FTIR) were used to characterize the surface morphology and optical properties of samples. FESEM images revealed a uniform distribution of graphene within the PVP-MWCNT nanocomposite. The FTIR spectra confirmed the nanocomposite information is successful with apperaring the presence of primary distinct peaks belonging to vibration groups that describe the prepared samples.. Furthermore, found that the DC electrical conductivity of the prepared nanocomposites increases with increasing MWCNT concentratio
... Show MoreThe inhibition effect of crude juice of green and black olive on cancer cell line (RD) in vitro has been studied by depending on micro titration system . Eleven different concentration starting from (916-960) mg/ml of crude juice respectively ,for three periods of exposure(24-48-72)hours. The resulted showed that the inhibition effect dependent on type of olive fruit juice ,concentration of dose ,time of exposure and the high concentration of both type of olive juice increased the growth of cell line while other concentration caused decrease in different rates ,moreover the black juice was more effective than green and 48 hours' time exposure was the best for inhibition.