P3HT:PCBM-based organic solar cells : Optimisation of active layer nanostructure and interface properties.

Organic solar cells (OSCs) have attracted a significant attention during the last decade due to their simple processability on a flexible substrate as well as scope for large-scale production using role to role technique. Improving the performance of the organic solar cells and their lifetime stability are one of the main challenges faced by researchers in this field. In this thesis, work has been carried out using a blend of Poly(3-hexylthiophene-2,5-diyl) (P3HT) and [6,6]-Phenyl C[61] butyric acid methyl ester (PCBM) as an active layer in the ratio of (1:1) (P3HT:PCBM). The efficiency and stability of P3HT:PCBM-based solar cells have been examined using different methods and employing novel materials such as1-[N-(2-ethoxyethyl) pent-4-ynamide] -8 (11), 15 (18), 22 (25) -tris-{2-[2-(2-ethoxyethoxy) ethoxy]-1-[2-((2- ethoxyethoxy) - ethoxy) methyl] ethyloxy} phthalocyaninato zinc (II) (ZnPc) to construct a ternary hybrid as the active layer. Controlling the morphology and crystallinity of P3HT:PCBM active layer was carried out using different solvents including chloroform (CF), chlorobenzene (CB) and dichlorobenzene (DCB) and their co-solvents in the ratio of (1:1) to dissolve the P3HT:PCBM blend. Optimum morphology and crystallinity were achieved using a co-solvent made of CB:CF with the obtained solar cell exhibiting the highest performance with PCE reaching 2.73% among other devices prepared using different solvents. Further device performance improvement was observed through optimization of active layer thickness with studied thickness falling in range 65-266 nm. Measurements of the PV characteristics of the investigated OSC devices have revealed optimum performance when active layer thickness was 95 nm with PCE=3.846%. The stability of the P3HT:PCBM-based devices on optimisation of the active layer thickness has shown a decrease in PCE of about 71% over a period of 41 days. Furthermore, P3HT has been blended with different fullerene derivatives (PC[60]BM, PC[61]BM, PC[70]BM and PC[71]BM) and the active layers were processed using the optimum solvent as well as optimum film's thickness.These PCBM derivatives have different lower unoccupied molecular level (LUMO) and different higher occupied molecular level (HOMO) positions, which subsequently influence the PV parameters of the OSCs such as the device open circuit voltage (V[oc]) and its built-in potential (V[bi]). P3HT:PC61BM-based blend has exhibited the highest device performance with PCE reaching 4.2%. Using the above mentioned optimum parameters, the P3HT:PCBM-based devices have been subjected to post-deposition annealing at different temperatures in the range 100-180°C. Efficient device performance was ascribed to P3HT:PCBM layers being subjected to post-deposition heat treatment at 140°C with PCE=5.5%. Device stability as a result of post-deposition heat treatment has also been shown to improve with PCE degrading by about 38% after 55 days.The use of interfacial layer is found to play a key part in modifying the solar cell performance; using electron transport layer (ETL) such as aluminium tris(8-hydroxyquinoline) (Alq3) as a solution processable layer has contributed in increasing PCE to 4.25%, while, using PEDOT:PSS as a hole transport layer (HTL) doped with metal salts has significantly contributed in increasing PCE to reach 6.82% in device when PEDOT:PSS was doped with LiCl aqueous solution. Stability study for the device based on HTL has shown degradation in the PCE from 6.82% to around 1% over 96 days. Using ETL and HTL simultaneously in a complete device has shown a further enhanced PCE reaching 7%. In a further study, doping the P3HT:PCBM with the novel ZnPc hybrids (SWCNTs and reduced graphene oxide (rGO) are covalently and non-covalently functionalised to ZnPc) with the weight ratio of (1:0.01) has significantly altered the solar cell device properties. The best performance is based on P3HT:PCBM blended with ZnPc-SWCNTs-co bonded as a ternary active layer demonstrating device PCE of 5.3% compared to a reference device based on bare P3HT:PCBM blend with PCE of 3.46%

Study the Rheological and Mechanical Properties of PVA/CuCl2 by Ultrasonic

Some of physical properties of polyvinyl alcohol dissolves in distilled water had been studied before and after adding different weights of copper (II) chloride (CuCl2), the Rheological properties shows that the densities variation are intangible and shear viscosity are responsible for reducing velocity, bulk modulus and transmittance the absorption coefficient of ultrasonic waves and relaxation amplitude are increasing with adding copper (II) chloride because there will be more molecules in solution and this lead to more attenuation against wave propagation. Keywords: PVA solution, mechanical properties, rheological properties, ultrasound technique

Study the Rheological and Mechanical Properties of PVA/NH4Cl by Ultrasonic

Some of physical properties of polyvinyl alcohol dissolves in distilled water had been studied at different concentration (0.25%, 0.5%, 0.75%, 1.0%, and 1.25%) before and after adding 1gm from NH4Cl for all concentrations, the Rheological properties such as shear viscosity, relative viscosity and reduced viscosity are measured and after that the ultrasonic velocity had been measured by ultrasonic waves system at frequency 40 KHz, other mechanical properties had been calculated such as absorption coefficient of ultrasonic waves, relaxation time, relaxation amplitude, specific acoustic impedance, compressibility and bulk modules. Another acoustic mechanical properties were measured and calculated at a same time such as the ultrasonic wave amplitude before and after absorption by solution were showed on oscilloscope ,then we calculated absorption coefficient. The results show that all these properties are increasing with the increase of the polymer concentration except velocity is decreasing with increase the concentration; results also show that when adding NH4Cl these properties are increasing. Keywords: PVA solution, mechanical properties, rheological properties, ultrasound technique

Enhancement Mechanical Properties of Barium Chloride by Adding Copper Chloride using Ultrasonic Technique

Some of physical properties of BaCl2 dissolves in distilled water had been studied at different concentrations (0.05%, 0.1%, 0.15%, 0.2%, 0.25% and 0.3%) (gm./ml) before and after adding (0.3)gm of CuCl2 for all concentrations , the mechanical properties such as ultrasonic velocity had been measured by ultrasonic waves system at frequency 25 KHz, other mechanical properties had been calculated such as absorption coefficient of ultrasonic waves, relaxation time, relaxation amplitude, specific acoustic impedance, compressibility and bulk modules. The results show that all these properties are increasing with the increase of the polymer concentration except compressibility is decreasing with the increase of the concentration; results show that when adding CuCl2  these properties are increasing except compressibility is decreasing. Results also shows that adding CuCl2 to BaCl2 enhances the ultrasonic absorption coefficient as a result of high values after addition. Keywords: BaCl2 solution, CuCl2 solution, mechanical properties, ultrasound technique.

Synthesis, Characterization and Gas Sensor Application of New Composite Based on MWCNTs:CoPc:Metal Oxide

تم تخليق فثالوسيانين الكوبالت الجديد المعوض (CoPc) باستخدام مواد البدء النفثالين -1،4،5 ، ثنائي هيدريد حامض التراكربونيك (NDI) عن طريق العملية الجافة. تم تصنيع الأوكسيدات المعدنية (60٪ Ni3O440٪ -Co3O4) مع الأنابيب النانوية الكاربونية متعددة الحوائط (F-MWCNTs) لإنتاج المتراكب النانوي (F-MWCNTs / MO)  (E2) وخلطها مع CoPc لإنتاج (F-MWCNT) / CoPc / MO) (E3). تم فحص هذه المركبات باستخدام طرق تحليلية وطيفية مختلفة مثل H-NMR1  ، مطياف FTIR ، حيود الأشعة السينية (PXRD)  (2θ o = 10-80) ، مطيافية رامان ، وقياس الطيف المرئي للأشعة فوق البنفسجية. ثم تم فحص نشاط هذه المواد لاستشعار غازات (NH3 ، ميثانول ، أسيتون).كان تركيز المحاليل المستخدمة 0.2 ملغم من المادة المحضرة  لكل1 مل من الامونيا, الميثانول والاسيتون. تم أجراء القياسات بدرجة حرارة 298 كلفن.  كانت الأشكال السطحية للمواد المحضرة غير متجانسة.The synthesis of new substituted cobalt Phthalocyanine (CoPc) was carried out using starting materials Naphthalene-1,4,5, tetracarbonic acid dianhydride (NDI) employing dry process method. Metal oxides (MO) alloy of (60%Ni3O4 40%-Co3O4 ) have been functionalized with multiwall carbon nanotubes (F-MWCNTs) to produce (F-MWCNTs/MO) nanocomposite (E2) and mixed with  CoPc to yield (F-MWCNT/CoPc/MO) (E3). These composites were investigated using different analytical and spectrophotometric methods such as 1H-NMR (0-18 ppm), FTIR spectroscopy in the range of (400-4000cm-1), powder X-rays diffraction (PXRD, 2θ o = 10-80), Raman spectroscopy (0-4000 cm-1), and UV-Visible spectrophotometry (0-800 nm). Then the activity of these materials was investigated as a gas sensing of (Ammonia, Methanol and Acetone). For each case, 0.2 mg/.mL of the prepared Copc, Copc/MWCNT, Copc/MWCNTs–MO was dispersed in 1m of ammonia, methanol and acetone at 298K. The surface morphology of the prepared materials was heterogeneous

Preparation and study the mechanical properties of CMC/PVA composites by sound waves

The CMC/PVA composite membranes were prepared by casting method, the appropriate weight of CMC was variable (0.1, 0.15, 0.2, 0.25 and 0.3 gm) was dissolved in (25ml) of distilled water under stirring and heat (80?C) for (30 min.) then add the PVA with different weights (0.2, 0.4 and 0.6 gm) for each CMC weight. In order to evaluate the mechanical properties of CMC/PVA composite the ultrasonic measurements were performed at the samples , these properties are ultrasonic velocity, compressibility, acoustic impedance and bulk modulus, were made at fixed frequency (f =2.5 KHz), another acoustic mechanical properties were measured and calculated at a same time such as the ultrasonic wave amplitude before and after absorption by composite were measured using oscilloscope ,then we calculated absorption coefficient , transmittance and the reflected pressure ratio of the sound. It was found that there is significant relationship between ultrasonic velocity and material properties also results show that adding PVA affects on the density then the absorption of the ultrasonic waves inside the composites samples. Keywords: Carboxy methylcellulose; polyvinyle alcohol; mechanical properties; casting method

Study the Mechanical Properties of (PVA/SI) Prepared by Sol-Gel Castting Method

The PVA/Si composite was prepared by casting method, the weight of PVA is constant (1gm) while the Si powder were (0.02, 0.04, 0.06, 0.08) gm, the densities of the samples were measured in the weight method. In order to evaluate the mechanical properties of PVA/Si composite the ultrasonic measurements were performed at the samples , these properties are ultrasonic velocity, compressibility, acoustic impedance and  bulk modulus, absorption coefficient, the relaxation amplitude and transmittance were analyzed at different frequencies (25 and 30) kHz. It was found that there is significant relationship between ultrasonic velocity and density on the material mechanical properties. Keywords: Mechanical properties, polyvinyl alcohol, Composite, casting method

Preparation organic-metallic compounds from Schiff bases and study so mechanical properties

The research includes preparation ligand (DMAB) and its Complexes with Cu (II) as symbol (M1), Fe (III) as symbol (M2) and Cr (III) as symbol (M3). The identity of prepared compounds has been characterized by spectral methods, infrared ray (IR) and measures melting point (m.p.). Also the research included study of the Mechanical properties by ultrasonic waves velocity technique at 40 KHz frequency, absorption coefficient of ultrasonic waves, relaxation time, relaxation amplitude, specific acoustic impedance compressibility, and bulk modules has been measured and all the results showed that all properties decrease with increase ultrasonic waves velocity except the specific acoustic impedance and bulk modules which was increase with increase velocity and all the results compared with similar compound.Schiff bases, organic- metallic compounds, ultrasonic method, mechanical properties