Former achievements through this contract

We will summarize the achieved research work by classifying the work done in three categories:

A. Solar Energy Systems

 

 

A.1 Amorphous Silicon Thin Film Solar Cells:

This activity aims to fabricate thin film silicon based solar cells by Plasma Enhanced Chemical Vapor Deposition (PECVD) on glass substrate coated by transparent conductive electrode. Currently, we have optimized the deposition parameters of each layer and in the phase of the cell integration. We use advanced characterization techniques such as XRD, LBIC, and Ellipsometery to characterize the material and device beside the conventional characterization techniques of the cell performance.

 

A.2 Silicon Wafer Surface Passivation Using Al2O3 deposited by Atomic Layer Deposition

 

Conventional solar cells based on crystalline silicon have a market share more than 85%. The current technology uses silicon nitride as an ant-reflection coating and also to passivate the surface. We employ atomic layer deposition to apply a very thin layer of the aluminum oxide directly on the silicon surface. This thin layer passivated the surface and hence enhances the cell efficiency. Our goal is to make the Al2O3 layer thick enough to well passivate the surface and in the same time thin enough to enable tunneling current from the metal to the silicon. If successful, this idea will save the process step used in industry to open the insulator (passivation layer) or firing to form the contact. The evaluation of the passivation quality is done by measuring the minority carrier life time by Sinton method as well as mapping is done by the Semilab tool using microwave reflection.

 

A.3 Amorphous Silicon and Thin Film Photovoltaics:

 

Addition of carbon into p-type “window” layers in hydrogenated amorphous silicon (a-Si:H) solar cells enhances short circuit currents and open circuit voltages by a great deal. However, a-Si:H solar cells with high carbon-doped “window” layers exhibit poor fill factors due to a Schottky barrier-like impedance at the interface between a-SiC:H windows and transparent conducting oxides (TCO), although they show maximized short circuit currents and open circuit voltages. The impedance is caused by an increasing mismatch between the work function of TCO and that of p-type a-SiC:H. Applying ultrathin high-work-function metals at the interface between the two materials results in an effective lowering of the work function mismatch and a consequent ohmic behavior. If the metal layer is sufficiently thin, then it forms nanodots rather than a continuous layer which provides light-scattering effect. We demonstrate 31% efficiency enhancement by using high-work-function materials for engineering the work function at the key interfaces to raise fill factors as well as photocurrents. The use of metallic interface layers in this work is a clear contrast to previous work where attempts were made to enhance the photocurrent using plasmonic metal nanodots on the solar cell surface. Carbon (C) incorporation in the p+ hydrogenated amorphous silicon (a-SiC:H) is highly desirable for a-Si:H based solar cells because of the following reasons: (i) it increases the band gap of the p+ layer to ~2 eV, which allows a majority of the sun light to pass through the thin p+ layer (~15 nm) and get absorbed in the underlying intrinsic a-Si:H layer, and (ii) it enhances built-in potential of the Si:H p-i-n stack, resulting in enhanced short circuit current (JSC) and open circuit voltage (VOC). Hence, it is a desire to incorporate the highest possible C % in the p+ a-Si:H. However, C incorporation results in a Schottky barrier at the p+ a-SiC:H/transparent conducting oxide (TCO) interface, which degrades the fill factor (FF) of the solar cell. We present a method that increases the C incorporation in p+ a-SiC:H but without adversely affecting the FF, by adding a thin layer of hydrogenated amorphous germanium (a-Ge:H) buffer at the p+ a-SiC:H/TCO interface. The presence of a- Ge:H can either minimize or eliminate the Schottky barrier. We demonstrate ~25% enhanced efficiency of the a-Si:H solar cell by using the a-Ge:H interfacial buffer compared to that without an a-Ge:H interfacial layer

 

 

B. Water Technology

 

 

B.1. Reusable composite nanostructure for effective water recycling

 

Semiconductor nanoparticles offer promising and feasible approaches to solve such environmental challenge with high efficiency and cost effective processes owing to their superior photocatalytic behavior. An ideal photocatalyst should be stable, inexpensive, non-toxic and, highly photoactive. Titanium dioxide (TiO2) nanoparticles has attracted much attention because of its abundance, nontoxicity, strong oxidizing activity, and long-term chemical stability. Nevertheless, the large band gap (3.2 eV) and fast electron-hole pair recombination, which is in the order of nanoseconds, are yet key challenges for technology utilization and hence commercialization. In addition, the photocatalytic process occurs while suspending the TiO2 in the wastewater being treated after which it is required to be separated and collected for recycling. This adds a new challenge for practical utilization of this material.

            Magnetic separation provides a convenient approach for removing and recycling magnetic nanostructures. Superparamagnetic Fe3O4 nanoparticles is a preferred choice to construct magnetic photocatalysts, owing to their superparamagnetic behavior, high magnetization, and chemical stability. As a result, the photocatalyst can be collected after successful treatment so that it can be recycled. However, direct coating between TiO2 and Fe3O4 induces ineffective and unstable magnetic photocatalyst due to photodissolution. Such phenomenon is induced due to direct electronic interactions between the photoactive TiO2 and the magnetite nanoparticles, leading to oxidation of magnetite nanoparticles, and the formation of Fe2TiO5 as an impurity phase {FormattingCitation}[1]. Hence, the combination needs careful attention during development in order to retain the photocatalytic performance of TiO2.

            Herein, our objective is to design efficient and recyclable photocatalyst nanocomposite that incorporates several types of nanoparticles for degradation and removal of organic/inorganic pollutants under solar irradiation as well as deactivation of waterborne pathogens. In principal, we aim to develop a novel photocatalyst of a core/shell structure that comprises super paramagnetic cores and functional TiO2 shells. In this project, magnetite Fe3O4/ hollow mesoporous TiO2 [Fe3O4 / HMPT] nanoparticles will be developed. The Fe3O4 nanoparticles will be coated with a thin layer of SiO2 in order to keep preventing photodissolution between the yolk (Fe3O4) and the shell (HMPT). In order to extend the photoresponse of [Fe3O4 / HMPT] yolk/shell nanophotocatalyst into the visible range, combining with different carbonaceous nanomaterials (ex: 2D Graphene, 1D Carbon nanotubes “CNTs” and 0D Carbon nanodots “C-Dots”) will be investigated. The extraordinary properties of these carbonaceous nanomaterials, including excellent charge transfer, optical, and chemical, properties, opened the way to be applied in photocatalysis applications. A comparative study to evaluate the efficiency of [Fe3O4 / HMPT] yolk/shell nanophotocatalyst using different carbon nanostructures will be performed.

            The proposed approach develops a nanotechnology based solution on for wastewater treatment and recycling with several advantages. First, the designed nanophotocatalyst is expected to exhibit efficient utilization of solar spectrum. Second, develop a good understanding of nanophotocatalysis’ using different carbon allotropies. Finally, a prototype of this platform will be designed implemented and tested to investigate future scaling-up to implement a cost effective wastewater treatment systems which will have a positive impact on the wastewater reuse and it subsequent economic impact.

 

B.1.2 Development of a Postgraduate Program in Integrated Water Technologies (IWaTec) for Egyptian Students

            During the last few years, the Egyptian government together with other international organizations has carried out a number of programs and developed strategies aiming to efficiently manage the usage of water resources. All these activities, however, require the availability of trained and well-educated individuals. There are a few teaching and training courses for water science offered by a number of universities and public organizations in Egypt. However, there is still a demand for several well-structured and international programs to fill the gap and provide the Egyptian fresh graduates with the adequate and up to-date theoretical and practical knowledge available for water technology.

            In this proposal, we are aiming to develop a six-month intensive program focusing on integrated water technologies (IWaTec) for Egyptian master students. The program will be a joint effort between the University of Duisburg-Essen (UDE) and Fayoum University (FU) together with two research centers in Egypt. Throughout the program, 24 Egyptian students will have the opportunity to learn and understand the theoretical as well as the practical aspects of water chemistry, water treatment, water management, and engineering of water systems. The students will also be involved in research projects that will be performed in close collaboration between German and Egyptian scientists. The main portion of the requested funds will be allocated to cover the expenses of short visits for the students and the German and Egyptian scientists during the course of the project.

 

  1. Biotechnology

 

The objectives of the EGNC in this area are to create (1) the needed infrastructure (tools and satellite labs around the country). (2) the critical mass of researchers (at all levels - through education: courses, workshops, and practical training) necessary to carry microfluidic research and make an impact, and (3) erect seed projects with key institutes and industries that will be the end user of this research. Along these objectives, the following has been achieved:

-    Introduced for the first time at the Egypt-Japan University for Science and Technology (E-JUST) a graduate level Microfluidic course entitled: Introduction to Microfluidic and its Applications. The course (MTR 609) was offered during fall 2014 at as part of the Mechatronics and Robotics Engineering department curriculum (School of Innovative Design). (Satisfying in part objective 2)

-    Provided technical assistance and member of the received Capacity building grant to establish the Microfabrication facility at E-JUST (STDF- Capacity Building # 12417 for LE 4,999,950 - Title: "Micro Fabrication Center of Excellence (MF-CoE) received December 2014. Still working on specifying the lab capability and tool specifications. (Satisfying in part objective 1)

-    Provided technical assistance for the Nanotechnology Center at Mansoura University for the last 2 years that was crowned by the center’s opening in December 2014 and acknowledging Cairo University for its assistance. Microfluidic is one of the three main research directions of this center (Satisfying in part objective 1)

-    Developed a senior year microfluidic-based graduation project with 4 students at the Alexandria University. This is the first microfluidic project offered at Alex. Univ. The project successfully produced a microfluidic device and the system required to separate blood cells from plasma. This is the first step for most of the diagnosis tests. All four students receive an “Excellent” grade for their project. (Satisfying in part objectives 2 and 3)

-    Developing a digital on-chip PCR in collaboration with E-JUST and Alex Biotechnology, a small provider of biotechnology laboratory equipment and reagents based out of Alexandria. The objective is to develop a simple, non-infringing device to be sold with a PCR start-up kit. (Satisfying in part objective 3)

 

C.1. Projects - Nanobiotechnology and Biosensors:

We present a new strategy to construct redox-active molecular platforms to be used as molecular rectifiers with tunable and amplifiable electronic readout. The approach is based on using ligand-receptor biological interactions to bioconjugate electroactive bio-inorganic building blocks onto metal electrodes. The stability of the self-assembled interfacial architecture is provided by multivalent macromolecular ligands that act as scaffolds for building-up the multilayered

structures. The ability of these electroactive supramolecular architectures to generate a unidirectional current flow and tune the corresponding electronic readout was demonstrated by mediating and rectifying the electron transfer between redox donors in solution and the Au electrode. The redox centers incorporated into the assembled architecture in a topologically controlled manner are responsible for tuning the amplification of the rectified electronic readout, thus behaving as a tunable biosupramolecular diode. Our experimental results obtained with these redox-active bio-supramolecular architectures illustrate the versatility of molecular recognition-directed assembly in combination with hybrid bio-inorganic building blocks to construct highly functional interfacial architectures. Layer-by-layer (LbL) deposition of polyelectrolytes within nanopores in terms of the pore size and the ionic strength was experimentally studied. Anodic aluminum oxide (AAO) membranes, which have aligned, cylindrical, nonintersecting pores, were used as a model nanoporous system. Furthermore, the AAO membranes were also employed as planar optical waveguides to enable in situ monitoring of the LbL process within the nanopores by optical waveguide spectroscopy (OWS). Structurally well-defined N, N-disubstituted hydrazine phosphorus-containing dendrimers of the fourth generation, with peripherally charged groups and diameters of approximately 7 nm, were used as the model polyelectrolytes. The pore diameter of the AAO was varied between 30-116 nm and the ionic strength was varied over 3 orders of magnitude. The dependence of the deposited layer thickness on ionic strength within the nanopores is found to be significantly stronger than LbL deposition on a planar surface. Furthermore, deposition within the nanopores can become inhibited even if the pore diameter is much larger than the diameter of the G4-polyelectrolyte, or if the screening length is insignificant relative to the dendrimer diameter at high ionic strengths. Our results will aid in the template preparation of polyelectrolyte multilayer nanotubes, and our experimental approach may be useful for investigating theories regarding the partitioning of nano-objects within nanopores where electrostatic interactions are dominant. Furthermore, we show that the enhanced ionic strength dependence of polyelectrolyte transport within the nanopores can be used to selectively deposit an LbL multilayer on top a nanoporous substrate.

 

C.2 Collaborations:

Egypt-Japan University for Science and Technology (E-JUST), Egypt

Mansoura University, Egypt

University of Alexandria, Egypt

Alex. Biotechnology (SME based out of Alexandria- Egypt)

 

C.3 Main Achievements:

-          New course added to the Mechatronics and Robotics Engineering department curriculum (School of Innovative Design) at E-JUST.

-          Introducing microfluidics-based senior projects at the University of Alexandria

-          Assisted Mansoura University in establishing their Nanotechnology Center completed December 2014. Currently assisting E-JUST in establishing their microfabrication facility and member of their received “capacity building” grant for 4,999,950 EGP. Both activities are part of the Biotechnology outreach efforts.

  1. Graphene Science and Technology

 

D.1 Projects

 

D.1.1. Development of Touch Screen Platform based on Carbon Nanostructres

During the last 20 years, modern electronic devices have evolved such that many of them are multifunctional and people are increasingly depending on them. Computer, cell phones, GPS, and electronic sign pads are few examples of those devices. There are two main common features of those devices; first, they are currently manufactured of silicon based microelectronics that are flat and planner. Second, they all run a kind of ICT software. However, recent market trend studies indicate that the future of these industries will depend on flexible, bendable, and/or stretchable wearable electronics which at the same time affordable for consumer market. Consequently, new class of materials and technologies has to be developed. Those materials have to maintain the electronic and optoelectronic properties of the current standard technologies and at the same time should satisfy the new requirements of being flexible. Potential materials are organic conducting polymers, single and multiwall carbon nanotubes, and graphene. We believe that the later (nanotubes and graphene) will have the edge due to their exceptional mechanical and electronic properties which will lead to faster and more endure electronic devices. Here in this document we are proposing the development of fixable electronic devices based on our patented knowhow and related experience.

            The proposed work focus on developing nanotechnology based solutions for next generation carbon based flexible electronics where it is expected to drive the consumer electronics and communications market in the near future. Our proposed approach is to utilize wet-chemistry based processes at ambient conditions to develop transparent conducting electrodes (TCE); this is in contrast to the current expensive technologies such as lithography, plasma and vacuum deposition that involves high energy and expensive infrastructure. This approach will allow developing cheaper and convenient multifunctional electronic devices that will fierce the demand on flexible electronics to be adopted by more consumers. The expected new functional devices can monitor physiological conditions, sense environmental changes, integrate the input data, process it, and finally communicate it with decision making centers. All these functionalities will only be achievable with the support and the development of ICT industry to collect, process, and communicate information.

 

D.1.2. Post-CMOS Graphene-Based Transistors

Despite the success of graphene in many domains, the material’s zero band-gap property has limitations for applications which require a fraction of an eV bandgap and/or a stable doping mechanism, such as computer logic switches. We are working on a novel approach for doping graphene nanomeshes. This approach is capable of doping graphene nanomeshes in a rigid band way, i.e. with no effect on the graphene band structure. Furthermore, our novel approach doping approach is ultra stable, and offers precise control on the doping level.

 

D.1.2. Graphene Nanomesh-Based Support Templates for Nanocatalysis Applications

Catalytic nanoparticles agglomeration is a common and critical problem in the field of catalysis. It severely limits the efficiency of various applications aiming to increase the catalytic efficiency by using small-sized catalytic nanoparticles. In this project, we study the use of functionalized graphene nanomesh structures as superior support templates that are capable of eliminating the mobility of various catalytic nanoparticles.

 

D.1.3. Graphene Nanomesh-Based Structures as Novel Anion and Cation Chelating Agents

Chemical agents chelating various anions and cations are used in many industrial and medical applications. Graphene nanomeshes possess crown-like structures that can be utilized for chelating different ions. In this project, we have explored the use of functionalized graphene nanomeshes for hosting different anions and cations. Comparing them to commonly used agents, we have found them to have superior ion-binding. We are currently studying their utilization in some applications such as chelation therapy.

 

D.1.4. Graphene Nanomesh Spintronics

Graphene nanomeshes are novel graphene based structures that possess an electronic band gap that is of interest for nanoelectronics. In this project, we dope graphene nanomesh structure with magnetic particles with the goal of inducing spin-dependent transport. Our results have implications on the use of these graphene structures in spintronic devices.

 

D.1.5. Molecular Sensing with AlN-Patched Graphene Structures

Molecular sensing is a emerging field with many applications across the industrial spectrum. Sensing accuracy, precision, and reliability are important aspects of any sensing device. Graphene has peculiar electronic properties that can be utilized for many applications such as sensing. A sensing event that encompasses a charge transfer can be precisely detected by a graphene sensing template. Aluminum is known easily adsorb well to various molecules of interest. In this project, we study the electronic properties and applications of AlN-patched graphene structures. Molecules considered include glucose, glucosamine, as well as some industrial gases.

 

D.2. Collaborations:

            Zewail City of Science and Technology, Egypt

            British University in Egypt

IBM T.J. Watson, USA

KAUST, Saudi Arabia

           

D.3. Main Achievements:

- Joint Study Agreement (JSA) with IBM T.J. Watson Research Center.(Oct 2012 – Oct 2016)

 

E. Nanoscience and Nanomaterials

 

E.1. Projects:

 

E.1.1 Phase Change Memory

Phase change memory (PCM) is an emerging technology that relies on storing information in the material amorphous or crystalline phases. The state of the material can be reversibly switched by applying either laser or voltage. In collaboration with UNAM, Bilkent University, we have developed a new material which has unique properties to be suitable to fabricate random access memory based on the phase change properties. Beside the experimental fabrication and characterization of the new material, we use COMSOL and MATLAB to model the phase change properties of the prepared nanostructured devices.

 

E.1.2 Tailoring self-organized nanostructured morphologies in kilometer-long polymer fiber

While nanowires and nanospheres have been utilized in the design of a diverse array of nanoscale devices, recent schemes frequently require nanoscale architectures of higher complexity. Novel top-down, iterative size reduction (ISR)-mediated approaches have recently been shown to be promising for the production of high-throughput cylindrical and spherical nanostructures, though more complex architectures have yet to be created using this process. We fabricate complex nanostructures by combining ISR and thermal- manipulation processes for the production of nanostructure arrays from a multi-material macroscopic preform. We achieved fabrication of As2Se3 complex nanostructures like spirals and cylinders in a long PVDF fiber and explained the formation mechanism by performing COMSOL multiphysics simulation.

 

E.1.3 Lithium Ion Batteries

Rechargeable Li-Ion batteries use graphite as an anode. Graphite has a theoretical capacity of 370 mAh/g. This project aims to replace the graphite with nanostructured silicon which has a capacity up to 4212 mAh/g. We achieved anode capacities more than 500 mAh/g silicon and targeting capacities larger than 2000 mAh/g in the coming two years. This technology is protected by a US patent and has potential to go to industry either inside or outside Egypt.

 

E.1.4 Polymer Physics and Structure/Property Relationships

Changes in structural order, which occur when amorphous polyethylene terephthalate (PET) is crystallised by drawing and then subsequent annealing are studied. Real time wide angle X-ray fibre diffraction is used to obtain information about the microstructural changes taking place during drawing and subsequent annealing. The diffraction patterns obtained proved the existence of a liquid crystalline transient mesophase prior to crystallisation. The development of both the mesophase and the crystalline structure are also studied using small angle X-ray scattering during annealing of uniaxially drawn samples held at constant strain. These experiments proved the absence of any microstructure associated with the mesophase and that significant microstructural changes take place only when crystallisation starts to occur.The microstructure of 50% PET/PEN random copolymer crystallised by uniaxial drawing and subsequent annealing is investigated by twodimensional wide angle X-ray diffraction and high resolution scanning electron microscopy. Chemical etching was used to reveal the structure after drawing and subsequent annealing. The structure observed was found to be in the order of 100 nm. The results showed fibrillar microstructure parallel to the draw direction that could be associated with the presence of the smectic-A liquid crystalline transient mesophase as a result of the drawing. There was evidence of banding perpendicular to the draw direction when crystallisation started to take place. This banded structure was explained in terms of buckling of the thin polymer film perpendicular to the direction of the draw in an analogy similar to that of liquid crystalline polymers. The wide range of microstructure observed microscopically and reported here are, however, associated with crystallisation.

 

E.1.5. Excellence in Nano Science Education for the MENA Region (XNEM)

The main objectives of this project include:

- To establish a regional Master program in Nanoscale Science and Engineering for MENA postgraduate students. The program will be taught in English for duration of 2 years.

- To establish an online Nano Academy offering video lecture materials covering all aspects of nanoscience and nanotechnology. The lectures will address different levels i.e. high school, undergraduate and postgraduate students as well as teachers and professionals.

- To install inexpensive equipment and setups at the Arab universities to be used for practical training and students' research projects.

- To teach and train more than 25 students on the up-to-date knowledge available in nanoscience and nanotechnology.                                                                                              

- To develop a strong academic and research network between MENA and EU partners in nanoscience and nanotechnology.

- To build a strong link between academia and industry in nanotechnology.

 

 

E.1.6 Surface and Interface Engineering of Integrated Systems” (SURSYS)

The main aim of this proposal is to establish a scientific research group in Egypt that focuses on the surface and interface engineering of integrated systems such as solar cells, transistors and functional membranes. Novel and low-cost engineering methods such as soft lithography, inkjet printing and gravure printing will be utilized to control the surface and interface properties of these systems with the aim to enhance the device efficiency as well as to reduce the fabrication costs and complications. In addition, new and established theoretical models and calculations will be tested for the new designed surfaces and interfaces for devices such as solar cells. Fig. 1 shows a schematic description of the group, its partners, focus areas and potential funding programs.

The group will consist of a principle investigator (PI), a Co-PI and three graduate students. The group members will work closely with other partners from Egypt and Germany in well-defined seed projects as described below. The PI and Co-PI of the intended group have been graduated from well-known western institutions. Both of them will lead the group with the aim to develop an “effective and productive team” of young scientists. The group members will use the resources available at their partner institutions in Egypt (EGNC, FU) and Germany (UDE, TUD). The requested fund from “DAAD Line 4 Program” will be used to cover staff costs, travel and living expenses as well as costs for consumables and small tools. The graduate students who will be working in the intended group will be selected using transparent and well-known standards. As part of the wider objectives of the project, it is envisioned that the newly formed group will motivate aspiring Egyptian researchers from different fields to start similar activities. The intended group will seek to collaborate with other national and international partners as well as apply for funding from other programs to expand their activities and hire more students.

 

E.1.7 Inkjet Printing of Electronic and Optoelectronic Devices

Inkjet printing technique has attracted great attention as a method for fabricating electronic and optoelectronic devices on large areas and at low-cost. Unfortunately, while there has been tremendous progress made in the integration of inkjet printing into various electronic systems, the degraded resolution of inkjet printing versus conventional patterning techniques has proved to be a significant limitation of the same. In this proposal, the capabilities of inkjet printing for fabricating devices such as transistors, solar cells, and sensors will be explored. The possibility to increase the quality of the printed structures as well as the resolution will be examined at different printing parameters. The interaction between the ink and the substrate will be studied in details using different homogeneous and pre-patterned substrates as well as different inks. For pre-patterning of the substrates, microcontact printing and gravure printing will be utilized with the aim to control the wettability as well as the roughness of the substrates. To the best of our knowledge, the proposed approaches to enhance the resolution of the printed structures as well as understanding the mechanisms involved have not been studied in details in the published literatures. Within this project, graduate students from Egypt and USA will be trained on using these low-cost techniques for different applications. In addition, a detailed proposal for bigger grant will be prepared by the end of this project.

History

  • Industry workshop, January 2011
  • Technical seminars conducted at the Bibliotheca Alexandria, American University in Cairo, and Cairo University, and others.  (January 17th, 2010 – January 19th, 2010)
  • ITIDA Celebrate Launch of first Nanotechnology Research Center in Egypt. (June 14,2009)
  • Contract Signed with IBM. (September 20,2008)

project proposals were accepted for funding

  • Solar Energy System Design using Advanced Learning Aids (SOLEDA).
  • Inkjet Printing of Electronic and Optoelectronic Devices.
  • Development of a Postgraduate Program in Integrated Water Technologies (IWaTec) for Egyptian Students.

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