الانتقال الى المحتوى الأساسي

جامعة الملك عبدالعزيز

KING ABDULAZIZ UNIVERSITY

كلية العلوم - قسم الفيزياء

مقترحات بحثية متاحة لطلاب وطالبات الدراسات العليا بالقسم


Before submitting any proposal to the committee, please provide the following information

Number of students currently under your supervision
Whether the submitted proposal were submitted at the same time to the Deanship of Scientific Research at KAU for funding purpose or to any other organizations

State the percentage of plagiarism report of the proposal

The nature of research, either it is theoretical (Please mention it clearly in the proposal)
In case that the work is experimental, please provide the name of the equipment that will be used and its location?

Whether some of the pending work previously published in one of your publications?

The title must be accurate and specific reflect the experimental work and expected results

A short survey of the previous work in the same field

State new references to the subject

Please seek an advice of native English speaker to check errors in spelling, grammar and punctuation (The same should be done for the Arabic summary)

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أولا: مقترحات لطلاب وطالبات مرحلة الماجستير

 

Characterization of Commercially available Ge-core optical fibers for neutron and gamma beams dosimetry

superviser; Dr. Eid Abdel Munem  (eabdelmunem@kau.edu.sa)

Radiation dosimetry is a fundamental procedure used to confirm the delivery of prescribed radiation dose in cancer treatment process. Treatment procedure relies on previously established dose measurements in-vitro. Different types of dosimeters were used for the purpose. One important type used is TLD (Thermoluminescent Dosimeter), which exhibits good spatial resolution, made it the dosimeter of choice. Attention was diverted recently to optical fibres for the same purpose [1]. Attenuation of radiation in optical fibres [2], TL response [3], response to photons [3,4], to electrons [4,5], to protons [6], to alpha particles [7], to fast neutrons [8], and to synchrotron radiation [9] were studied. In the currently proposed study, commercial single mode optical fibres with Ge-core dopant are proposed. Another preliminary investigation of the response of Borosilicate glass neutrons is targeted. Standard neutron and gamma sources will be used

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Crystal Growth, morphology, structural, and optoelectronic performance of AgBiS2 Nanoparticle for solar cell application

superviser; Dr. Elmoiz Marghni Mkawi Mrzog and Profs; Yas Al-Hadeethi

Recently, the semiconductor materials research is directed across the advancement of easy, appropriate and non-harming to environment approaches for synthesis of nanostructured substances, which show remarkable characteristics from the positive point of view with highly possible applications[1]. Chalcogenide Silver Bismuth Disulphide (AgBiS2) nanoparticles (NP’s) have become the center of interest for intensive research. This is attributed to their unique physical properties and hopeful wide spectrum utilizations. They have many significant recent advances due to their exceptional mainly optoelectronic properties [2]. Furthermore,  AgBiS2  can also be utilized as a safe quantum dots due to their non-poisonous nature. In addition, AgBiS2 received extensive attention as a solar cell material, because its energygap (Eg=1.2eV) is close to the optical energy gap (1.4eV) of solar cell absorbers and AgBiS2 has a large absorption coefficient of 105 m-1. The later feature, beside their earth abundance; made those nanocrystals as a good candidate in the investigation of solar cells. They show similar  short-circuit current densities  and conversion efficiences[3]

AgBiS2 nanoparticles will be grown utilizing reaction approaches and a two-stage successive ionic layer adsorption since they are simple and cheap as compared to other thin film deposition mechanisms

The aim of this proposal is to investigate the growth parameters and characterization of AgBiS2 nanoparticles prepared by by hot injection method followed by heating in Teflon-lined stainless steel autoclaves. First, the student will prepare AgBiS2 nanoparticles using hot injection method focussing on optimal growth parameters such as precursor concentration, complex agent, additives and salt source to obtain good quality of nanoparticles. During the second step, structural, morphology optical and electrical properties of AgBiS2 nanoparticles will be investigated using a variety of techniques namely; (XRD), (XPS), and (TEM). The objectives of this investigation are to see if synthesized AgBiS2 nanoparticles will have stoichiometric composition and good crystallinity.  In the third step, AgBiS2 thin film will be prepared using spin-coating method (6000 rpm,60 s) on Mo: Ag -coated glass substrates. AgBiS2 thin films will be annealed of for 30 min in nitrogen inert atmosphere fourth, AgBiS2 thin film will be characterized using FESEM, (EDS) mappings, (XRD), (XPS), and (TEM). Finally, AgBiS2 solar cell device will be built using the structure Glass /Mo: Ag/ polymer hole-transport layer / AgBiS2/i-ZnO/ ITO to study open-circuit voltage (V), a fill factor (FF), a short-circuit current density (JSC), power conversion efficiency  under AM 1.5 illumination. In this work, AgBiS2 nanoparticle and thin films preparations will be carried out in the physics department labs.

While the Characterization part, such as Field Emission Scanning Electron Microscope FESEM, Raman spectra, X-ray photoelectron spectroscopy (XPS), Current–voltage (I–V) characteristics, Energy-dispersive x-ray spectroscopy (EDS) mappings will be carried out at the core labs of KAUST and at the NANO research center at King Abdulaziz University

Refrences : [1] H.E. Katz, Recent advances in semiconductor performance and printing processes for organic transistor-based electronics, Chemistry of Materials, 16 (2004) 4748-4756. [2].D. Liu, D. Cai, Y. Yang, H. Zhong, Y. Zhao, Y. Song, S. Yang, H. Wu, Solvothermal synthesis of carbon nanotube-AgBiS2 hybrids and their optical limiting properties, Applied Surface Science, 366 (2016) 30-37. [3]. B. Bellal, M.-H. Berger, M. Trari, Physical and photoelectrochemical properties of spherical nanoparticles of α-AgBiS2, Journal of Solid State Chemistry, 254 (2017) 178-183

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Challenges and reliability of an underwater laser radiation propagation

superviser; Profs; Yas Al-Hadeethi & Ali Abdeldayem

Duties of student

Design and build a prototype underwater optical communication simulatorInvestigate all challenges influencing link performance like turbulence, absorption and scattering of laser radiation and draw conclusions regarding the optimal conditions needed for an efficient communication system

Preface

More than 96% of the water on the Earth is in the form of oceans. Therefore, there is currently a great interest in exploring the underwater environment for a variety of reasons, including climate changes, study of marine animals, marine algae and other marine resources and monitoring of oil platforms, which requires an effective and reliable means of communication. The information of the propagation of light will provide significant information in namely laser applications on underwater materials processing such as laser welding and cutting of underwater metals like in the case of treating cracks in the columns of bridges built into deep water. Underwater optical communication technology can also be used to ensure the safety and control of underwater oil pipelines continuously for signs of corrosion and leaks that may cause environmental disasters. Accordingly, it will provide an alternative to the current use and dependence on divers to inspect the pipelines, which is very complicated and expensive given the length of these marine pipelines. It is very practical to send a robot able to dive and scan the pipelines continuously and then send information through underwater optical communications. The laser optical communication system can easily send signals from the sea floor directly to a boat on the surface in real time. Not only that, but it can do many other tasks

Advantages of Underwater Communication Systems

 

For any communications systems to be considered as reliable and efficient to meet the nowadays demands of an advancing world, the systems should ensure confidentiality of the information. which means system is capable to protect information from unauthorized disclosure. It should also provide integrity of information which means protect information from unauthorized transfers or changes, and ensure that the information is accurate and complete. It also should ensure availability of information when needed.

 

Underwater optical communications systems justification

 

Information communications systems and computers have revolutionized and become an important and indispensable facility in our daily lives. Because the technology occupies a large role, the systems that rely on them have become high-value targets for those who want to misuse them and try to tear them or even destroy them. The increasing reliance on information technology is the structure and extension of industrial and commercial information services. All this has created a legitimate security concern associated with institutions, including the industrial, defense, petroleum sectors. Therefore, there is a real need for information management, policy design, information security, detection and prevention of threats to information and emergency planning in case of communication link exposed to natural, environmental or human damage.  Certainly, one may argue that optical fiber communications networks are characterized by high penetration immunity and reliability. However, there are many factors that renders optical fiber links render not functioning. Accordingly, there is a need to consider underwater communication systems which over comes all the problems, including damage or deterioration as well as natural disasters contribute to poor communications efficiency and security.

The risks of each environment or location vary, therefore, the design of the communication system should reflect the nature of these risks, as well as the nature of the for example industrial facility. High explosive chemical facilities (like petroleum) take into account the use of appropriate communications equipment such as those that do not cause electric spark to avoid disasters

However, the greatest harm is the intentional human danger and can be reduced by understanding the importance of information protection and monitoring. Fiber-optic lines (fiber or optical fibers are glass or plastic wires not exceeding 1/8 of the thickness of a human hair and used to transmit information in optical communication networks) are highly immune but free space underwater communications still hve several advantages over optical fiber communication

 

Needed Apparatuses

1-The Transmitter

The transmitter is the green laser system which is available in the department               

The transmitter is the source of the laser beam. There are many lasers used in this field, but what determines the choice of laser is the operating requirements that must be provided by the laser, which are

(A) The laser must have a high power (not less than several watts depending on the range)

(B) The laser has a very low water absorption by the particles and plankton

present in water and high susceptibility to water.

(C) The laser has reliability in operation, long operating life, and is small in size as in solid-state lasers, helium-neon lasers and carbon dioxide lasers.

(D) Ensure the safety of the human eye as in the case of the use of solid-state lasers with wavelengths greater than (1µ m) and carbon dioxide or carbon dioxide.

(2) Receiver: The Receiver (will be purchased simply from local market)

The receiver includes both the optical telescope and a set of photodetectors

(2-1) Optical Telescope: The Optical Telescope

  There are many candidate designs for optical telescopes. The appropriate design should provide a diameter of aperture for the collection of radiation and a suitable field of view (FOV (

 

The Detectors (to be purchased)

One photo detector or Array Detector is usually used to convert the incident light intensity into measurable electrical signals. One of the most important factors that determine the type of detector is high sensitivity. There are several things to consider when selecting a detector: physical size, cost, resistance to natural conditions and conditions of use, but in most cases the wavelength of the detected signal is the primary factor in the detector

 

Type of detector used

There are two types of detectors widely used. These are photomultiplier, where light electrons are injected through a vacuum, Phorodiodiodes or photoconductors where photons are generated in the semiconductor material. In any case, we are looking for high quantum efficiency.

In the infrared region, many photon detectors are used, the most important of which are the detectors (HgCdTe) and (PbSnTe), which work in the type of photovoltaic and cooled liquid temperature of liquid nitrogen (77k) to detect the wavelength (10.6 µ m) where these detectors were characterized by high sensitivity and speed Their response. These reagents can also be used at room temperature, but the sensitivity of the detector will fall due to a decrease in carries life time and an increase in the concentration of non-pure carriers. Refrigerated reagents (HgCdTe) (29), (30). Figure 3 shows the reagent used for each wavelength.

Low-frequency and high-temperature systems (190k) are used like HgCdTe-type while high-frequency and low-temperature systems (77k and> 58 Hz) are used as hydrodynamic detection systems (HgCdTe)

 

(5) Optical and electronic components

(1) Acoustic - Optic Modulator

It is is used to obtain frequency modulation of the transmitted laser beam as well as offset of laser frequency by diffraction. When some materials fall under the influence of multiplier sound waves, they suffer periodic changes in their refractive index. When the sound wavelength is within the wavelength of the light, the material behaves as a Diffracion Crating. Acoustic frequency changes the diffraction angle 

                                                              

References

Zeng, Z., Fu, S., Zhang, H., Dong, Y. and Cheng, J., 2016. A survey of underwater optical wireless communications. IEEE Communications Surveys & Tutorials19(1), pp.204-238

Johnson, L.J., Green, R.J. and Leeson, M.S., 2013. Underwater optical wireless communications: depth dependent variations in attenuation. Applied optics52(33), pp.7867-7873

Simpson, J.A., Cox, W.C., Krier, J.R., Cochenour, B., Hughes, B.L. and Muth, J.F., 2010, September. 5 Mbps optical wireless communication with error correction coding for underwater sensor nodes. In OCEANS 2010 MTS/IEEE SEATTLE (pp. 1-4). IEEE

Arnon, Shlomi. "Underwater optical wireless communication network." Optical Engineering 49, no. 1 (2010): 015001

Kaushal, Hemani, and Georges Kaddoum. "Underwater optical wireless communication." IEEE access 4 (2016): 1518-1547

Johnson, L.J., Jasman, F., Green, R.J. and Leeson, M.S., 2014. Recent advances in underwater optical wireless communications. Underwater Technology32(3), pp.167-175

Boucouvalas, A.C., Peppas, K.P., Yiannopoulos, K. and Ghassemlooy, Z., 2016. Underwater optical wireless communications with optical amplification and spatial diversity. IEEE Photonics technology letters28(22), pp.2613-2616

Ghassemlooy, Z., Arnon, S., Uysal, M., Xu, Z. and Cheng, J., 2015. Emerging optical wireless communications-advances and challenges. IEEE journal on selected areas in communications33(9), pp.1738-1749

 

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Structural and magnetic investigations of hydrothermaly prepared cobalt nanoferrite as candidate for hyperthermia applications

superviser: Prof. Yas Al-Hadeethi and Prof. Saleh Al-Hineti


It is well known that many biological processes operate on the nanometer length scale and that the basic building blocks of nature are nanoscale materials.  For example, the human cell has a size of about 10,000 nanometers and the cell nucleus contains the DNA molecule, which is two meters long but only 2 nm in diameter.  Thus it is immediately clear that any serious attempt to address biological processes and problems should be conducted at the level of nanoscale science and engineering – that is, within the realm of nanomedicine. In the not-so-distant future, major advances in surgical tools, life-saving procedures, and revolutionary drugs are likely to be based on nanotechnology. One of the goals of this new venture is to launch a high-technology research which would be at the forefront of research in nanotechnology-driven advances in medicine to capture the unprecedented global opportunities of the new era of medical practice. Accordingly, the present research project is within the framework of the research on nanomaterials to be used as biomedical tools for cancer treatment through different processes among them what is called hyperthermia. Thermotherapy or hyperthermia is a type of cancer treatment of living cells in which tissues are exposed to high temperatures of up to 113 Fo. This can be achieved by introducing some magnetic nanomaterials such as nanoferrites into the infected tissues and  using an external magnetic field to raise their temperature in order to destroy them. Therefore, more investigation is needed to discover suitable magnetic nanoferrite which satisfies the aforementioned goals.The student will be involved in preparing biocompatible magnetic nanomaterials such as nanoferrites with controlled properties using hydrothermal route which will be used for thermotherapy objectives in biomedicine. The structural, morphology, thermal and magnetic properties of these nanomaterials will be investigated using variety of advanced techniques such as XRD, TG, SEM, VSM. Moreover, the student will design and construct suitable electronic circuits for creating the external magnetic field and monitoring the temperature. By the end of the day, student will be able to draw conclusions from solid state physics viewpoint regarding the fundamental magnetic properties of the magnetic nanomaterials and the possibility of using them in hyperthermia applications by specialist research groups in biomedicine science

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Carbon Nanotubes Optical Rectenna as a solar Energy Harvester

Supervirer: Dr. Ahmed Obaid AlZahrani

The aim of this project is to fabricate an optical rectenna that converts electromagnetic radiation into electricity. The student will learn how to use plasma enhance chemical vapor deposition (PE-CVD) to grow vertically aligned carbon nano-tubes as an array of antennas. The student will also learn how to deposit a thin insulator on the tubes using Atomic Layer Deposition (ALD) and a top electrode will be deposited using thermal evaporation. The device will be characterized, by the student,  in dark and under infrared and visible illuminations

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Investigating atmospheric losses of a free space optical Communication System and disaster managment

superviser: Prof. Yas Al-Hadeethi and Dr. Ali Hasanien


In this work, student will construct a prototype FSO system and study atmospheric attenuations like absorption, scattering and scintillations effects. Also, he adopt  optical approaches to prove that FSO is a highly secured approach as compared to counterparts towards all possible schemes of intrusion

 

 

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Improvement the Performance of Fiber Bragg Grating (FBG)  as a Temperature Sensor  by different methods

superviser; Prof. Mahran and Prof. Sharif Nafee

In the recent years, the advancements and needed of optical fiber have improved and reshaped fiber optic technology so that optical fibers like amplifiers and reflected components (FBG) have become important with“telecommunication”. Due to huge telecommunication application, there is an improvement for the performance of the FBG as reflectors, filters, temperature sensors, pressure sensors and so on. Student will study the new methods to improve the temperature sensitivity of the FBG sensors. Also, he will use the simulation programs to execute this improvement. Main superviser

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Monte Carlo simulations of doses using pencil-beam model of high energy treatment photons

Main superviser: Dr. Hossam Donya

The accurate calculation of doses during external radiotherapy sessions is necessary. Recently, the models used for this purpose have been the point kernel, pencil-beam and collapsed cone superposition/convolution combination models. In this proposal, tallying pencil-beam influences based on Monte Carlo (MC) simulations will be investigated by scoring a volume of interest in different up-to-dated detectors via a water phantom centered perpendicular to the axis of irradiated areas of 5 cm x 5 cm, 10 cm x 10 cm, 20 cm x 20 cm, 30 cm x 30 cm and 40 cm x 40 cm at a depths ranged from 0 cm up to 40 cm. The fluence will be calculated for each mono-energetic photon ranging from 0.25 to 6 MV at increments of 250 keV. The output of the four fluence kernels along the depth z around the central axis will be categorized for both the primary and secondary photons and electrons. The  aim is to establish databases for pencil-beam kernels for each category. For validation purposes, other MC simulations will be carried out for fluence calculations and dose calculations as produced by the predetermined poly-energetic spectra peer references for different LINAC models. The net results will be published through related international journals

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Nonlinear Optical Measurements of Some Novel Dyes

Supervisor: Prof. Ali Razvi and Prof. Ahmed Bakry 

Nonlinear Optical materials are increasingly in demand for many applications. Some of them are; optical switching for all optical computers, optical limiting for safety of eyes and instruments, plasmonic enhancement and frequency upconversion, etc. Hence finding new materials which have favorable nonlinear optical properties is very important. This can be done detailed characterization of these materials. Recently a lot of interest is generated in organic dyes, some of them have very high nonlinear parameters suitable for the above applications. In this project we propose to study third-order nonlinear optical properties of some newly synthesized dyes. The nonlinear refraction and nonlinear absorption of these novel materials can be studied by various techniques. A relatively simple yet very sensitive technique called the z-scan technique would be used for this study. Continuous wave (CW) and pulsed tunable lasers would be employed to study the nonlinear response of these materials at several wavelengths and laser powers. The students would first get acquainted with the theoretical aspects of Nonlinear Optics, through specialized courses. He/she will get trained on operation and safety aspects of using lasers. He/she would setup the experimental systems and then measure the nonlinear optical properties of some known materials and then proceed to some new dyes in solutions at varying concentrations

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Structural, Optical and Electrical Characterization of NiO Thin Films Prepared by spray pyrolysis Technique

superviser Prof. Mohamaed Saleh and Prof. Saleh Al-Heniti

Nickel oxide (NiO) thin films have attracted recently an increasing interest due to their promising physical properties. Due to their interesting  structural, electrical, optical and chemical stability, NiO thin films have found a large number of applications in different fields namely: optoelectronic devices, light emitting diode, electrode  for p-type dye sensitized solar cells, memory devices[2], buffer layer in organic solar cells electrochromic devices, hydrogen sensing, smart windows, photo electrochemical water splitting, organic photovoltaics, antiferromagnetic. Most of metallic oxide are n-type semiconductor. Whereas, NiO is a p- type. Thus thin films of  this material are a good partner to other n- type semiconductors  which can find potential applications in the heterojunction fabrication science. Additionally, despite the developed efforts, the p-n homojunction with a single metallic oxide type  was not fully succeeded due the difficulty of producing p-type of naturally n-type metallic oxide semiconductor such ZnO. Literatures have shown that NiO thin films were prepared by different physical and chemical routes such as pulsed laser deposition (PLD), electron beam evaporation, DC and  RF magnetron sputtering, Photo-assisted Metal Organic Chemical Vapour Deposition, sol-gel, successive ionic layer adsorption and reaction, spray pyrolysis . However, few reports with some limitations have been reported about the fabrication of NiO films by spray pyrolysis method. Moreover, spray pyrolysis is a commonly well established and coast effective technique that has been widely used for various metallic oxides thin films synthesis.   It is regarded as a chemical vapor deposition. The main advantages of this technique including thin films processing at atmospheric pressure on large surface. It is a simple and non-expensive technique, it does  not require any vaccum system. Moreover, spray pyrolysis technique is based on the solution atomization to a droplets mist mechanically by using compressed air or ultrasonic waves. The droplets are sprayed on a heated surface subsequently a pyrolysis reaction occurs to form a solid deposit. Several metallic oxides and chalcogenures thin films were prepared by this method such as ZnO, SnO2, CuZnSnS, ZnS…etc. The aim of this proposal is to investigate the deposition parameters and characterization of NiO thin films prepared by spray pyrolysis technique. A systematic optimization of the deposition parameters namely : substrate temperature,  precursor solution concentration , annealing and doping will be considered in the present study. Student will performed following: Set up of the spray pyrolysis system and test of films deposition, deposite NiO thin films by varying the different deposition parameters namely: Solution molarity , Substrate temperature.   In order to specify the candidate technological applications of NiO thin films, structural, optical and electrical characterization of the prepared film will be investigated

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Microwave Synthesis of Nickel Hydroxide Nanomaterials for Supercapacitors

supervisers: Dr. Nuha Alhebshi and Prof. Faten Al-hazmi

Supercapacitors, which are also known as electrochemical capacitors, have many advantages for energy applications because of their high-power density and long cycle life as well as being environmentally friendly. In addition, they can bridge the power and energy gaps between traditional physical capacitors and secondary batteries/fuel cells. Therefore, supercapacitors have been widely used in electric vehicles and advanced energy storage devices. nickel hydroxide, an important material in physics and chemistry, that has many applications in engineering including, significantly, batteries. Nickel hydroxides are also important components of the surface layers that form either electrochemically or by the corrosion of nickel metal and nickel-based alloys. Today, these materials are involved in a diversity of practical applications, which include photocatalysis1-3, electrocatalysis and electrosynthesis4-6, supercapacitors7-9, electrochromic devices, electrochemical sensors9-13 and more. Microwave heating is concerned as a promising route for fast bulk heating which can result in high reaction rates in short reaction time and an increase in the product yield in comparison with conventional heating routes. Therefore, microwave technology is a new technology for the development of the green chemistry and it is an important method for synthesis of nanostructures with uniform particle size distribution and versatile morphology.  Microwave process has to be simple and easy to operate, rapid heating in comparison with the conventional one and reduce the time reaction13-18. In this work we will synthesis Ni(OH)2 nanoparticles via a facile microwave-assisted hydrothermal process. Moreover, the structural properties of the produced nanomaterials will be tested in terms of X -ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Energy and Dispersive X-ray Spectroscopy (EDXS) measurement. Finally, the electrochemical performance of Ni(OH)2 supercapacitor electrodes will be evaluated in terms of specific capacitance19-21, cyclic stability, energy and power densities. The supercapacitor evaluation results will be measured using Cyclic voltammetry (CV), Galvanostatic cycling of charging-discharging (CD) and electrochemical impedance spectroscopy (EIS).

Objective: Synthesize Ni(OH)2 nanoparticles using a facile microwave-assisted hydrothermal process and improve the specific capacitance, cyclic stability, energy and power densities of Ni(OH)2 supercapacitor electrodes.    

Plan

Preparation of Ni(OH)2 nanoparticles for supercapacitor electrodes

Characterization of Ni(OH)2 nanoparticles using XRD, SEM, etc

Electrochemical measurements of Ni(OH)2 supercapacitor electrodes

Publications in International Reputed Journals

Preparation of the Seminar

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Synthesis and characterization of nanostructured BAPbI 3 perovskite solar cell applications

Advisor; Elmoiz Marghni Mkawi Mrzog (MOIZMERGHNI@YAHOO.COM.MY )

Increasing consumption of energy and decreasing supply of fossil fuels have led attempts to develop renewable energy resources without pollution. Photovoltaic solar cells convert the energy of sunlight directly into electricity based on the photovoltaic effect. Recently, organic–inorganic halide perovskite solar cells have achieved rapid development because of their low-cost input materials, superior material properties such as tunable bandgap, high open-circuit voltage (Voc), long electron–hole diffusion lengths and excellent absorption. In this project, we will construct high efficiency and stability planar-structured BAPbI3 (BA= CH3 NH3 and NH2CH=NH2) perovskite solar cells via aqueous process. The student would first prepare the nano perovskites by solvothermal method. Then, the improvement of nano-composites properties will be by determine the optimal growth parameters that influence the precursorsm which expected to obtain good quality. The second step, investigate the structural, morphology, electrical property of these nanomaterials using variety of advanced techniques. The third step, Prepare perovskites thin film using spin-coating method on FTO-coated glass substrates, followed by study optical properties, morphological, electrical and structural of perovskite thin film. The project comprehensive study conclusion based on data obtained expected to enhance the fabrication of the PV cells and enhance its efficiency. In this work, thin films preperations will be carried out in the physics department labs. Such as,Teflon Lined Hydrothermal Autoclave, Hot plat , Spin- coating, Three-necked flask, Furnace, Centrifuge, RF sputtering, Electron –beam evaporation. While the Characterization part, such as Field Emission Scanning Electron Microscope FESEM , Energy-dispersive x-ray spectroscopy (EDS) mappings, Current–voltage (J–V) characteristics, X-ray photoelectron spectroscopy (XPS), Raman spectra will be carried out in the KAUST and NANO center at King Abdulaziz University

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ثانيا: مقترحات لطلاب وطالبات مرحلة الدكتوراة

Spectroscopic Diagnosis of Cancer Tissues

Prof. Ali Razvi and Prof. Ahmed Bakry 

Cancer is a dreaded disease and large populations get affected from it, a large number of deaths occur every year due to this disease. Certain types of cancers have higher incidence in developed world and certain others are more prevalent in the developing nations. The main reason for large number of deaths is the late detection/diagnosis of cancer. If detected in the early stages, where the disease can be managed better. Hence there is a need for techniques which can detect the presence of cancer with high sensitivity, has high discrimination capability and accuracy. Several  techniques are being investigated as an alternative diagnosis tool. The spectroscopy techniques have the added advantage that the can be repeatedly applied in situ/ in vivo without the deleterious effects of repeated biopsy. However, there are only a few systematic studies on effectiveness of discriminating between premalignant and malignant conditions in certain types of cancers. In this work student will investigate whether this could be done successfully, to begin with in vitro, i.e. in the laboratory. These techniques are referred to as Optical Biopsy along sile with other techniques such as: Laser induced fluorescence (LIF) spectroscopy and fluorescence imaging have been studied as potential noninvasive diagnostic tools for differentiating normal and neoplastic tissues. The technique involves illumination of tissue with monochromatic laser light and recording the fluorescence spectrum collected from the same site. LIF may utilize the naturally occurring tissue fluorophores (autofluorescence) or exogenous fluorophores. Autofluorescence techniques offer a number of advantages, including avoidance of potential side effects of added dyes or drugs. The fluorescence spectral profile of the tissue provides information not only about their architecture and organization but also about their metabolic state and concentrations of fluorescing molecules, which can be correlated to histological changes. Fluorescence spectroscopy is being attempted as a diagnosis modality with the potential to bridge the gap between clinical examination and invasive biopsy. Student in this work will help setting up an experimental facility for carrying out research in vitro on LIF autofluorescence of samples collected after biopsy, and establish the efficacy of the technique in discriminating against the normal, benign, premalignant and malignant tissues. After successful completion of this work, we intend to setup a facility for an in vivo detection of oral cancer lesions. The proposed research has high relevance to society as it involves health care of people affected or likely to be affected by this dreaded disease

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Effect of gamma radiation on the performance of macro-bending EDFA for different types of glass-host materials

Advicors: Prof. Sherif Nafee

Research Problem: In telecommunication systems, the needed for greater band width behind the L-band becomes very important to amplify large scale of optical signals. The extension of the conventional C-band is execute by erbium doped fiber amplifier (EDFA), which can amplify the signals in the window 1520-1610 nm, which offer also increasing the overall capacity of the wavelength division multiplexing(WDM). Study the effect of both radiation and macro-bending on the performance of EDFA which gain and noise of the amplifier to improve the performance of EDFA for large band-width communications. Research Objectives: The research objectives are 1- Study the effect of glass-host materials on the radiated macro-bending EDFA theoretically. 2-Using the simulation programs to execute this improvement and their effects.  Importance of the Research:  To increase the amplification performance of EDFA, we must suppressing the amplified spontaneous emission (ASE), this can be achieved by bending loss of EDFA. The study of macro-bending EDFA is greatest problem and must solved in addition to the external sources like radiation which affected the performance of EDFA and must be studied. Literature Review: Because erbium doped fiber amplifier (EDFA) have gained very important acceptance in communication industry, the parameters which affected the performance of EDFA must be studied and improved. These parameters are the concentration of erbium, the cross sectional of host materials, temperature, length of the amplifier and other parameters, in addition external parameters like macro-bending loss and radiation sources, which improve the performance of the amplifier in Wave Division Multiplexing (WDM). Hypothesis: The effect of changing the parameters which the cross section area and bending loss and gamma doses on the gain coefficient and noise figure of the Erbium doped fiber amplifiers which help in changing performance of the amplifier. Research Methodology and Procedures: Developing a mathematical model that can achieve the accumulated list of the published results and used in the complete study of the performance of the Erbium-doped fiber amplifier through the some controlling parameters of macro-bending loss of the fiber and effect of gamma radiation. Research Limitations:   The limitations of the study our research are depend on the simulation program and simulations analysis if found. The thesis contains five chapters Chapter 1 shows the aim of this thesis. Chapter 2 presents some background knowledge about optical fibers and EDFAs. Chapter 3 describes the mathematical model which including basic equations and detailed numerical procedure for the gain and noise figure which depend on the gamma radiation and macro-bending effect. Chapter 4 displays the obtained results. Chapter 5 concludes the results of this thesis with its discussion and the future work. Expected Findings: The expected findings is to make comparison between calculated results with opti-system simulation  results with update version is available

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X-ray absorption fine structure studies of Zr‑based glassy alloys

Advicors: Dr. Yahia Swilem and Prof. Saleh Al-Heniti

Non‑crystalline materials such as metallic glasses are possessing an interesting elastic properties  inform of combination of high strength, larger elastic elongation, lower Young’s modulus, higher corrosion resistance and better nanoscale imprint ability. The formation of quasicrystal with nanoscale in Zr-based glassy alloys have attracted much attention in the aspects of the scientific interests as well as industrial applications. Zr-based glassy alloys have been employed as practical materials and tested for real application in items such as sporting goods, watch components, electromagnetic casing and wave shielding sheet, power inductors, magnetic field identification systems, micro-geared motor parts, pressure sensors, surface covering materials and as main components in medical instruments. The formation of nanograins in the matrix of the metallic glass materials indicates the possibility of a significant difference in structure between the phase of nanograins and the local atomic configuration of the glassy state, and hence their behavior is expected to be improved due to the strong influence of this property on the physical properties of the alloys. Therefore, understanding the atomic configuration by an effective probe is an important factor for controlling  the properties

In this work, the atomic configuration analysis of the clusters in Zr-Nb-Al-Ni-Cu glassy alloys can be carried out by investigating the atomic configuration around the Zr, Nb, Ni and Cu atoms using X-ray Absorption Fine Structure (XAFS) spectroscopy. XAFS techniques, including the Extended X-ray Absorption Fine Structure (EXAFS) and X-ray Absorption Near Edge Structure (XANES), provide a unique opportunity for determining the formation of their structure. These methods make it possible to determine the parameters of the local ordering of atoms such as coordination numbers, interatomic distances, the types of surrounding atoms, and Debye–Waller factors as well as the unoccupied electron level and charged states of atoms. Nanophase formation in Zr-Nb-Al-Ni-Cu alloys will be correlated with the addition of other elements, such as Mo, Ti, Cr, V and Nb to the alloys. In addition to XAFS technique, differential scanning calorimetry (DSC) as well as X-ray diffraction (XRD) measurements will be performed at different temperature to monitor phase transition from glassy state to crystalline states in such alloys. Moreover, the compositional analysis of the investigated alloys will be accomplished by considering the energy dispersive X-ray spectroscopy
Research plan of this work will include: prepareing Zr-based glassy alloys in Japan. Then the X-ray diffraction method will be used to confirm the glassy structure of the alloys. Phase transition of the glassy alloys to the crystalline state will be conducted using the DSC technique. Heating scheme of the samples to the corresponding nanocrystallization temperatures (Tx) will be done to study the early stage of the crystallization process. In situ high temperature X-ray diffraction measurements will be performed to monitor the structural changes as a function of temperatures. XAFS measurements will performed by collaborating with SESAME synchrotron at Jordon. XAFS data analysis can be achieved by well known licensed software such as FEFFIT package and FEFF 9 code. Elemental and compositional analysis will done by energy dispersive X-ray spectroscopy (EDX) 

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Synthesis and Characterization of Bioactive Glass /metal oxides composite for Biomedical Applications

Advicors: Prof. Faten Al-hazmi and Dr. Samah Eldera

The development and study of new glasses for biomedical and dental applications have attracted increasing interest in the past decades. Bioglass can be used in widely different applications depending on their microstructure, mechanical, physical and chemical properties. These properties are changing with composition and heat-treatment conditions to produce glass of specific properties. Different varieties of bioglass have been developed during the last years for biomedical and dental applications. The limited mechanical properties of bioglass and low toughness has prevented their use medical application in load bearing devices, so adding nonometal oxide will improve its mechanical and physical properties in orthopedic application of the bioglass
Recently, bioactive glass nanoparticles doped with Metal oxides nanostructured such as ZnO, Fe2O3, MgO and TiO, AgO, etc, because they have excellent properties and they are widely used in different applications such as medicine, foodstuff, water treatment, smoke suppressant, chemical sensor and so on. Metal oxides are widely used as biomaterials, wherein silver is doped to provide antimicrobial properties against bone infection
We have previously prepared metal peroxide nanostructures such as MgO, TiO, ZnO, MgZnO, AgO.... etc. we first reported the synthesis of one-dimensional MgO nanowires by a microwave hydrothermal method using magnesium acetate with urea as precursors. The antibacterial behavior of MgO nanowires concentration in solid media against Gram negative and Gram positive for different bacteria has been tested in detail. Furthermore, we synthesized TiO2 nanowires by using water in hydrothermal cell without any chemical catalysis i.e. free catalysis process
In this work, we will synthesis of metal oxide/ Bioactive Glass nanocomposite by microwave processes. Therefore, the interrelation among network structural and processing parameters will be studied in detail to understating the growth mechanism of nanomaterials. In the end, the applicability of as prepared nanomaterials will be examined as antibacterial application.
Objective
 To synthesize and characterize the metal oxide materials.
 To prepare and characterize of nanobioactive glass
 To prepare and characterize of metal oxide/ Bioactive Glass nanocomposite
 Study the physical and mechanical properties of the metal oxide/ Bioactive Glass nanocomposite
 Study the bioactivity of the prepared samples
 Study toxicology and biocompatibility
 In vitro test

Aim of study
Over the world, many researchers were prepared bioactive materials from glass, glass-ceramics, ceramics and composites. The famous compositions are: 45S5( in wt %: 45 SiO2, 24.5 CaO , 24.5 Na2O, , 6 P2O5) and 46S6 (in wt %: 46% SiO2, 24% CaO, 24% Na2O, 6% P2O5 ) were found by Hench [5].
Fast development in biomaterials gave more compositions with different structures. Also doping of biomaterials by some metal or metal oxides provided more importance for selective bio-treatment for many microbial diseases. AgO ,ZnO , Fe2O3 , CuO , … -doping biomaterials are useful to imparts it antibacterial effect [6]. Preparation of such materials in nano-scale form gives more affections because the more surface area the more effect
Use of microwave helps in doping metal salt with biomaterials (usually glass powder) and formation of nanoparticles

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Thermoelectric properties of some ternary chalcogenides

Advisor: Dr. Abdullah Al Shaikhi

Thermoelectric materials provide one of the possible alternative energy resources. However, efficiencies of these materials are still in need for more enhancement. To do this, deep understanding of the electronic and thermal transport properties is required. This proposal is an attempt in this line where theoretical investigations will be carried out to study the electronic and thermal transport coefficients in some compounds of a group of materials that have shown potential to be good candidates for the field of thermoelectric devices. This group is the ternary chalcogenides. The study will employ semi-classical and quantum mechanical approaches

Under this proposal, the electronic properties of some ternary chalcogenides will be investigated. This includes calculating energy band structures, Fermi energies, Seebeck coefficients and electrical conductivities. In addition to that, thermal conductivities will be calculated for these materials. Each component of the total thermal conductivity for each compound will be evaluated. Role of doping in these materials will be investigated. The study will provide a quantitative analysis of the factors which control the calculated transport coefficients. At the end the figure of merit will be quantified for these materials at different temperatures and carrier densities. Theoretical results obtained from this study will be compared with available experimental data

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Structural, Mechanical and Electrochemical Properties of Advanced Functional Materials

تم تحديد لجنة إشراف وطالبة دكتوراة

 Main Advisors: Prof. E. Shalaan

second Advisor Prof. F. Al-Marzouki

Student: Wafa Said Alghamdi

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Environmental Monitoring for radioactive hazards in Rabigh city, KSA

Main Advisors: Prof.ٍ Sherif Nafee 

Recently, many industrial activities were carried out on the Red sea coastal line, such as oil and gas treatment, mineral production, Cement manufacturing and water desalination, which produce a large amount of radioactive industrial waste, which may pollute the environment, some of which contain low radiation levels and another high level. the main environmental issues in the Red Sea geosystem are due to anthropogenic and tourism activities, oil pollution, fishing, water pollution, and disposal of solid waste. As a result, the shores will act as a repository for various contaminant types. Rabigh Governorate is located between two longitudes (410 13', 40010') and it is one of the coastal governorates in the Makkah region and stretches along the Red Sea coast with a facade of about 100 km to the west. The importance of the site is shown to Rabigh governorate where it is close to the holy capitals of Mecca and Medina and located on the regional coastal axis between Makkah and Jeddah and extends to Madinah and Yanbu in the north. It also has a local airport and a port along with the industrial centers represented by the refinery of Aramco and Arabian Cement, The relative importance of the province and its location has increased after the establishment of King Abdullah Economic City within the southern of the province. This study is essential to evaluate the radiological hazard to the inhabitants and staff of Port and factories, health or customers on periodically, also for provides the platform for estimating the future change in radioactivity levels due to exposure to the accumulation of waste in the coast. To achieve the present work, we will use gamma ray spectroscopy technique (co-oxial high pure germanium detector (HPGe) of 25% efficiency and FWHM 2.0 keV at 1332 keV) to measure the radioactivity levels of 226Ra, 232Th , 238U, 40K and 137Cs and to calculate the radiation hazard parameters. In addition, to identify the concentration of the detected elements, we will use the Energy-Dispersive X-ray Fluorescence spectrometer (EDXRF). All obtained results will be compared with the limits given by FAO/WHO, "United Nations Scientific Committee for the effects of Atomic Radiation" (UNSCEAR), and some published results



لمزيد من المعلومات واختيار المقترح المناسب للرسالة نرجو ارسال الطلب الى الإيميل التالي

 physics@kau.edu.sa 

مع ارسال نموذج  طلب عرض مقترح على رسالة علمية(اضغط هنا للحصول على النموذج) بقسم الفيزياء والسيرة الذاتية مختصرة جدا للمشرفين مع إضافة مكان عمل الممتحن الخارجي ودرجته العلمية

 

 

 

 

 

 

 

 

 

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آخر تحديث 12/9/2019 2:10:55 PM