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Article
Fabrication of electro spinning 1D ZnO Nano fibers as UVPhotoconductor
تكوين الياف نانوية لأوكسيد الزنك الاحادي الاتجاه بأستخدام البرم الكهربائي كموصل ضوئي للأشعة فوق البنفسجية

Authors: Raad S. Sabry --- Firas S. Mohammed --- Roonak Abdul Salam A.Alkareem
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2015 Volume: 33 Issue: 5 Part (B) Scientific Pages: 884-894
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

The electrospinning technique was used to fabricate 1D nanofibers of Zinc Oxide (ZnO). Polyvinylpyrrolidone (PVP) ̸ zinc acetate Nano fibers electrospun using solution containing PVP dissolved in ethanol and zinc acetate in distilled water were mixed, followed by calcination at 500°C for 3hours to remove the polymer. XRD pattern show the hexagonal wurtzite structure of ZnO NFs without any impurities. FESEM pictures show a network of nanofibers with diameters less than 100 nm and several micrometers in length of ZnO, these nanostructures increase the ratio of surface area to volume and improve the physical properties of the materials. The Photoluminescence (PL) of the films was studied and the energy gap and the optical properties were estimated. A photoconductor device was constructed by electroding the films with silver conducting electrode (IDE) using screen print method, The result shown that the resistance of the nanofiber films decrease dramatically when exposes to UV light. In addition, the change of conductivity with the change of wavelengths was studied also the photoconductivity was examined under different bias voltage.

تم استخدام تقنية الدوران اللولبي الكهربائي لتحضير الياف نانوية من اوكسيد الخارصين. تم الحصول على الالياف النانوية ل PVP و خلات الزنك من خلال ضخ محلول يتكون من PVP مذاب في الايثانول و خلات الزنك المذاب في الماء المقطر حيث تم مزجهما, يتبعه حرق للغشاء المتكون بدرجة حرارة 500 م° لمدة 3 ساعات للتخلص من البوليمر. يبين نمط ال (XRD) ان اوكسيد الخارصين يكون ذات تركيب سداسي و بدون شوائب. أظهرت صور FESEM شبكة من الالياف النانوية التي تتراوح اقطارها دون ال 100 نانومتر وطولها عدة مايكرومترات. ان هذه التراكيب النانوية تزيد من نسبة المساحة السطحية الى الحجم مما يؤدي الى تحسين الخصائص الفيزيائية للمواد. تم دراسة التألقية الضيائية وكذلك حساب فجوة الطاقة والخصائص البصرية للاغشية المحضرة. تم بناء الموصل الضوئي بعد تقطيب الاغشية ب (IDE) باستخدام طريقة الطباغة على الشبكة واظهرت النتائج انخفاضا كبيرا في مقاومة الالياف النانوية عند تعرضها للضوء ضمن المنطقة فوق البنفسجية


Article
Characterizations study ZnO-TiO2 nano rods thick films as Photo detector
دراسة خصائص الاغشیة السمیكة ZnO-TiO2 النانوية التركيب ك كاشف ضوئي

Authors: Raad Sadoon --- Osama AbdulAzeez
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2015 Volume: 33 Issue: 6 Part (B) Scientific Pages: 1075-1081
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

First,ZnO nanorod s were su ccessfu lly synthesized by simple evaporationmethod,u sing single stage controllable horizontaltu be fu rnace and qu artz tu be withou tcatalyst.The ZnO nano powd erwas mix ed with (10 and 20%)of TiO2 powd er(weightratio),then ZnO -TiO 2 thickfilms were synthesized u singsimple,low-cost efficient screen print techniqu e. The thick films were heated at 500 C ˚ for one hou rto remove the organic bind erand anyimpu rities.The prepared thickfilms were examined withX -Ray,and FESEM to stu d y the stru ctu raland morphology of the films,the X -ray results show that the films are polycrystalline with sharp and high intensity peaks indicating high crystalinity of the product.The FESEM pictures show nanorods with diameters less than 100 nm and several micrometers in lengthof ZnO withTiO 2 nanoparticles.ZnO -TiO 2 device was built up by electroding the thick films.The I-V characterization of the films were studied in dark and light,then photo detection parameters were estimated and it was found to be efficient and high response in UV range detection

باستخدام تقنیة التبخیر (nanorod s) في البدایة تم تحضیر اوكسید الخارصین بتراكیب نانویةالبسیط باستخدام فرن انبوبي وانبوبة كوارتز بدون عامل مساعد حیث تم تبخیر معدن الخارصین عند10 على التوالي. - درجة حرارة 7 00 م وبوجود غاز الاركون والاوكسجین وبنسبة خلط 90واستمرت العملیة مدة تم تصنیع اغشیة سمیكة من الخلیط باستخدام تقنیة الطباعة على الشبكة وھيبسیطة وذات كلفة واطئة وفعالة، ان ھذه الطریقة تعطینا اي تصمیم او ابعاد للغشاء وبالتصاقیة جیدةبین الغشاء والقاعدة. بعد ذلك تم تسخین الاغشیة المحضرة لمدة ساعة وعند درجة حرارة 500 مللتخل ص من الرابط العضوي واي شوائب اخرى. تم دراسة الخصائ ص التركیبیة و دراسة السطححیث اظھرت فحوصات الحیود X -ray,FESEM للاغشیة المحضرة بفحصھا ب باجھزة البالاشعة السینیة ان الاغشیة ذات تركیب متعدد التبلور مع قمم حادة ذات شدة عالیة مما یدل علىوباقطار اقل من 100 nano rod s تبلور جید للمادة، واظھرت صور المجھر الالكتروني الماسحنانومتر وباطول مختلفة تصل بضعة مایكومترات ل اوكسید الزنك ان اھذه التراكیب النانویة تعززوتحسن من اداء الكاشف. تم بناء الكاشف الضوئي بعد تقطیب الاغشیة وبنفس تقنیة الطباعة علىالشبكة وتم دراسة الخصائ ص الكھربائیة في الظلام والاضاءة وحساب العوامل الكشفیة للجھز حیثاظھر الكاشف استجابة عالیة كفاءة جیدة في منطقة الاشعة فوق البنفسجیة.


Article
Preparation and Characterization of TiO2 Nanostructure by TiCl4 Hydrolysis with Additive NaOH

Author: Rashed Taleb Rasheed
Journal: Al-Mustansiriyah Journal of Science مجلة علوم المستنصرية ISSN: 1814635X Year: 2017 Volume: 28 Issue: 2 Pages: 100-107
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Titanium dioxide (TiO2) nanostructures were synthesized via the hydrolysis of TiCl4 in alcohol /water solution/with sodium hydroxide solution in the ice-bath (0-5 ◦C). The particles were characterizedby using X-ray diffraction technique (XRD), spectroscopy of Ultra Violet-Visible (UV/ Visible) and infrared (FT-IR), atomic force microscope (AFM) and scanning electron microscope(SEM) analysis were used in order to gain information about the material, morphology,size and the shape of the particles.


Article
Nanocrystalline B-Silicon Carbide Films Prepared by TEACO2 Laser
أغشية كاربيد السليكون بالطور بيتا نانوية البلورات المحضرة بليزر TEACO2

Author: Hamad R. Humud حمد رحيم حمود
Journal: Iraqi Journal of Physics المجلة العراقية للفيزياء ISSN: 20704003 Year: 2011 Volume: 9 Issue: 15 Pages: 14-17
Publisher: Baghdad University جامعة بغداد

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Abstract

Thin films of microcrystalline and nanocrystalline -silicon carbide and silicon, where deposited on glass substrate with substrate temperature ranging from 350-400C, with deposition rate 0.5nm per pulse, by laser induced chemical vapor deposition. The deposition induced by TEACO2 laser. The reactant gases (SiH4 and C2H4) photo decompose throughout collision associated multiple photon dissociate. Such inhomogeneous film structure containing crystalline silicon, silicon carbide and amorphous silicon carbide matrix, give rise to a new type of material nanocrystalline silicon carbide in which the optical transmittance is governed by amorphous SiC phase while nanocrystalline grain are responsible for the conduction processes. This new material is promised for many new applications, lick high efficiency solar cell.X-ray diffraction patterns and scanning microscope images revealed that nanocrystalline SiC and Si films grew at substrate temperature above 400C, while completely amorphous films grew at substrate temperature 350C.

استعملت طريقة الليزر الحاث على ترسيب البخار كيميائياَ في تحضير أغشية كاربيد السليكون بالطور  بلوراتها ذات أحجام نانوية ومايكروية على قواعد من الزجاج وبدرجات حرارة ترسيب 400-350 درجة مئوية وبمعدل ترسيب 0.5 نانومتر لكل نبضة. وقد أنجز ذلك بليزرTEACO2. الغازات المتفاعلة(SiH4 and C2H4) تفككت ضوئياَ عبر التفكك متعدد الفوتونات المعزز بالتصادم. الأغشية المحضرة كانت ذات بنية تركيبية متنوعة من بلورات السليكون وكاربيد السليكون المغمورة داخل ماتركس من كاربيد السليكون ذو تركيب عشوائي. هذا التنوع في البنية التركيبية للغشاء جعله مادة جديدة من أغشية كاربيد السليكون النانوية. فيها النفوذية البصرية محكومة بالخواص العشوائية للـ SiC والتوصيلية تحكمها الخواص البلورية النانوية للغشاء. أغشية بهذه الخواص تُعّد بتطبيقات جديدة ومتنوعة منها الخلايا الشمسية عالية الكفاءة. بينت نماذج حيود الأشعة السينية وصور المجهر الإلكتروني الماسح أن الأغشية المحضرة عند درجة حرارة 400 درجة مئوية ذات تركيب نانوي لكل من SiC و Si والأغشية التي حضرت بدرجة حرارة 350 ذات تركيب بنائي عشوائي.


Article
Nanostructured Copper Oxide Thin Films Prepared by DC Reactive Magnetron Sputtering

Author: Mohammed A.K. Ahmed
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2017 Volume: 13 Issue: 2 Pages: 11-14
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

In this work, nanostructured copper oxide thin films were prepared by a dc reactive magnetron sputtering system. The structural and optical characterizations carried out on the prepared samples showed that the deposited CuO films were crystalline with a monoclinic crystal structure. The UV-visible spectra showed wide and high absorption spectral ranges that promote this material as an absorbing material for solar energy. Subsequently, the FTIR data showed the molecular structure of CuO with good agreement to the reference data.


Article
Nano/Micro Surface Texturing and Enhancing of Photovoltaic Cells Efficiency by Using UV Femtosecond Laser Pulses

Author: K.A. Alnaimee
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2011 Volume: 7 Issue: 2 Pages: 33-36
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

A fast laser texturing technique has been utilized to produce micro/nano surface textures in Silicon by means of UV femtosecond laser. We have prepared good absorber surface for photovoltaic cells. The textured Silicon surface absorbs the incident light greater than the non-textured surface. The results show a photovoltaic current increase about 21.3% in toe dimension laser textured area.


Article
Structural Properties of Semiconducting Nanostructures Prepared by DC Plasma Reactive Sputtering Method

Author: Noor I. Naji
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2014 Volume: 10 Issue: 3 Pages: 41-44
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

In this work, semiconducting nickel oxide (NiO) nanostructures were prepared by reactive dc plasma sputtering method. Magnetron was employed at the cathode to prepare these nanostructures and show the advantage of such device in the production of highly pure nanostructures. The sputtered nickel atoms were sputtered and oxidized in presence of oxygen in the Ar:O2 gas mixture of 4:1 ratio. Employment of magnetron results in formation of NiO only in the final samples according to the XRD analysis, increase the roughness and hence surface area of the produced NiO nanostructures, and finally decrease the particle size of NiO nanoparticles lower than 100nm. These improvements in the structural properties of the produced NiO make these nanostructures good candidates for specific applications, such as photodetectors, solar cells and electrochromic smart windows.


Article
Growth of Nanostructured CdO:In Films by Pulsed Laser Deposition

Authors: Ali A. Yousif --- Mazin H. Hasan
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2015 Volume: 11 Issue: 1 Pages: 15-19
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

In this work, indium-doped cadmium oxide (CdO:In) films were prepared by Pulsed Laser Deposition (PLD) on sapphire α- Al2O3 (006) substrate with thickness of about 100nm for all CdO:In films at different deposition conditions and the number of laser pulses was 100 pulses, by Nd-YAG Q-Switching second harmonic generation (SHG) pulsed laser with a wavelength of 532nm, repetition rate 10Hz and pulsed width 10ns. The effect of doping on the structure and morphology properties of the CdO:In films have been investigated by X-Ray diffraction (XRD), and Atomic Force Microscopy (AFM). The result showed that nano-crystalline and (111)-oriented CdO films were obtained at substrate temperature of 400°C, laser fluence 400mJ. The smallest grain size was obtained at 7wt.% In are 16.52nm, this indicates the superior nanocrystallinity of the films which also has observed from the SEM and AFM images. The surface morphology of the films reveals that presence of indium content in the structure did affect the surface morphology of the films significantly.


Article
Characterization of Laser-Ablated Nanostructured Al2O3/p-Si Solar Cells

Authors: Wafaa K. Khalef --- Sarya D.M. Al-Algawi --- Selma M. Al-Jawad
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2015 Volume: 11 Issue: 1 Pages: 29-32
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

This work was devoted for production of alumina (Al2O3) nanoparticles via pulsed-laser ablation technique from a solid alumina target immersed in distilled water with laser wavelength of 1064 nm. The produced NPs were characterized by UV-visible spectroscopy, atomic force microscopy (AFM), scanning electron microscopy (SEM) and Fourier-transform infrared (FTIR) measurements. FTIR spectra exhibit that bulk Al2O3 vibrational modes appear at <1000 cm-1, which indicates the formation of aluminum oxide nanoparticles. The SEM images showed that most of the obtained nanoparticles have spherical shape with a particle size of less than 1 micron. The absorption spectra of Al2O3 nanoparticles suspended in deionized water were recorded at room temperature using UV-visible spectroscopy. The absorption spectra show a strong peak at 240 nm arising from the presence of Al2O3 nanoparticles in combination with energy gap 4 eV. The n-Al2O3/p-Si solar cells were fabricated by depositing the aluminum oxide nanoparticles on p-type silicon wafers and glass substrates and then dried in an oven at 40°C for one hour to prepare and characterize heterojunction solar cells.


Article
Characterization of SiC/Si Heterojunction Fabricated by Plasma-Induced Growth of Nanostructured Silicon Carbide Layer on Silicon Surface

Author: Oday A. Hammadi
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2016 Volume: 12 Issue: 2 Pages: 9-13
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

In this work, p-type silicon substrates were etched by plasma-induced etching technique to form nano-scale rough surfaces. These surfaces were coated with ultra-fine graphite paste as a source of carbon to form layers of n-type silicon carbide by plasma-induced bonding technique. The plasma used for this purpose was generated by glow discharge of argon at 0.15 mbar and discharge power of 157.5W. The structures and morphology of these structures were introduced by x-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM). These tests confirmed the formation of nanostructured SiC layers on the etched Si substrates. Electrical characteristics showed that the formed n-SiC/p-Si anisotype heterojunction has an ideality factor of 0.45 and the built-in potential was measured to be 2.6V. This technique is reasonably efficient, low-cost and reliable to fabricate heterojunctions from nanostructured compound semiconductors on silicon substrates.

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