Download or read book Application of Single Wall Carbon Nanotubes as Transparent Electrodes in Cu In Ga Se2 Based Solar Cells Preprint written by and published by . This book was released on 2006 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present a new thin-film solar cell structure in which the traditional transparent conductive oxide electrode (ZnO) is replaced by a transparent conductive coating consisting of a network of bundled single-wall carbon nanotubes. Optical transmission properties of these coatings are presented in relation to their electrical properties (sheet resistance), along with preliminary solar cell resultsfrom devices made using CuIn1-xGaxSe2 thin-film absorber materials. Achieving an energy conversion efficiency of >12% and a quantum efficiency of80% demonstrate the feasibility of the concept. A discussion of the device structures will be presented considering the physical properties of the new electrodes comparing current-voltage results from the new solar cell structure and those fromstandard ZnO/CdS/Cu(In,Ga)Se2/Mo solar cells.
Download or read book Application of Single Wall Carbon Nanotubes as Transparent Electrodes in Cu In Ga Se2 based Solar Cells written by and published by . This book was released on 2006 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present a new thin-film solar cell structure in which the traditional transparent conductive oxide electrode (ZnO) is replaced by a transparent conductive coating consisting of a network of bundled single-wall carbon nanotubes. Optical transmission properties of these coatings are presented in relation to their electrical properties (sheet resistance), along with preliminary solar cell results from devices made using CuIn1-xGaxSe2 thin film absorber materials. Achieving an energy conversion efficiency of>12% and a quantum efficiency of ~80% demonstrate the feasibility of the concept.
Download or read book Carbon Single Wall Nanotubes written by Rajendra R. Khanal and published by . This book was released on 2014 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon single wall nanotubes (SWNTs) are hollow cylinders of graphene. They have unique mechanical, electrical, and optical properties that are directly influenced by their diameter and chirality. SWNTs are promising candidates for photovoltaics due to their high electrical conductivity and optical transparency. They do not require costly high vacuum processing conditions. SWNTs can be deposited onto different substrates using ultrasonic spray and membrane transfer methods. SWNTs have potential applications in solar cell technology. CdTe is one of the most promising semiconductor materials used for inexpensive solar cell technology. It has demonstrated a high efficiency of 20.4% in small area cells. One of the most important technological problems in CdTe solar cells is to make a good ohmic contact with CdTe for obtaining higher efficiencies. As CdTe has a very high work function, only high work functions metals can make a good ohmic contact with CdTe. However, no such metals with high work function than the work function of CdTe exist. Cu is used as a dopant in CdTe at the back contact in order to promote quantum mechanical tunneling. The record cell uses the Cu but the use of Cu causes a degradation of the device as Cu diffusion occurs through CdTe to the underlying CdS layer. In order to avoid such problems, Cu should not be used to create an ohmic contact with p-CdTe. The application of SWNT films without Cu at the back contact for CdTe solar cells has been investigated in this work. In this thesis, the use of SWNT films as a Cu free back contact in a CdTe solar cell and the corresponding device performance were investigated and compared with the performance of a device with the standard Cu/Au back contact. The main goal of this thesis work was the investigation of the fundamental physics involved in low contact barriers and the charge transport at the SWNT/CdTe and SWNT/Au interfaces.
Download or read book Carbon Nanotubes and Graphene for Photonic Applications written by Shinji Yamashita and published by Elsevier. This book was released on 2013-08-31 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt: The optical properties of carbon nanotubes and graphene make them potentially suitable for a variety of photonic applications. Carbon nanotubes and graphene for photonic applications explores the properties of these exciting materials and their use across a variety of applications.Part one introduces the fundamental optical properties of carbon nanotubes and graphene before exploring how carbon nanotubes and graphene are synthesised. A further chapter focusses on nonlinearity enhancement and novel preparation approaches for carbon nanotube and graphene photonic devices. Chapters in part two discuss carbon nanotubes and graphene for laser applications and highlight optical gain and lasing in carbon nanotubes, carbon nanotube and graphene-based fiber lasers, carbon-nanotube-based bulk solid-state lasers, electromagnetic nonlinearities in graphene, and carbon nanotube-based nonlinear photonic devices. Finally, part three focusses on carbon-based optoelectronics and includes chapters on carbon nanotube solar cells, a carbon nanotube-based optical platform for biomolecular detection, hybrid carbon nanotube-liquid crystal nanophotonic devices, and quantum light sources based on individual carbon nanotubes.Carbon nanotubes and graphene for photonic applications is a technical resource for materials scientists, electrical engineers working in the photonics and optoelectronics industry and academics and researchers interested in the field. - Covers the properties and fabrication of carbon nanotubes and graphene for photonic applications - Considers the uses of carbon nanotubes and graphene for laser applications - Explores numerous carbon-based light emitters and detectors
Download or read book Single Walled Carbon Nanotubes written by Melorina Dolafi Rezaee and published by American Chemical Society. This book was released on 2023-08-01 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: Single-walled carbon nanotubes (SWCNTs) are cylindrical one-dimensional nanomaterials made of single-layered graphene sheets. They possess unique properties because of their specific structure. Due to their distinct electronic structure and impressive thermal, mechanical, and optical properties, SWCNTs have great applications in biomedicine, energy storage, nanomechanical devices, etc. So far, many methods have been developed to synthesize SWCNTs. Despite the great achievements in the synthesis and applications of SWCNTs in the past few decades, many challenges remain. This primer will equip the reader with a foundational understanding of the growth mechanisms of SWCNTs and the advantages and disadvantages of the process and growth conditions of the various techniques. The reader will also learn how to relate the properties and structure of these materials to their specific functionality in the desired application.
Download or read book Carbon Nanotube Transparent Electrodes for Photovoltaic Applications written by Michael Wallace Rowell and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Virtually all solar cells require a transparent and conductive (TC) layer on the top surface that allows sunlight to enter the cell and photoexcited charge to be conducted laterally across the top surface. The impact on power conversion efficiency due to reflection, absorption, resistive losses and lost active area is a reduction by 10 -- 25 %, relative. Historically, doped metal oxides such as tin doped indium oxide (ITO) have been used. In the last several years, however, there has been renewed interest in this area with the development of several new nanostructured materials, many of which have the potential for performance, processing, and cost advantages. In the first portion of this work, we describe TC related efficiency losses in detail for the two major categories of solar cells. For thin film monolithically integrated modules, TC related losses can be as high as 25 % and for standard modules of cell strung together losses are typically 10 -- 15 %. For the purpose of developing new TC materials, we specify the material performance requirements for a competitive TC material and show the expected TC related efficiency losses in photovoltaic (PV) modules for any material of known electrical and optical properties. We then provide an overview of the leading nanostructured materials and show that carbon nanotubes (CNT) have basic optoelectronic material properties that are superior to traditional metal oxides. We exhibit the first demonstration of a highly flexible organic solar cell using carbon nanotube films as the TC. The achieved power conversion efficiency of 2.5 % is comparable to the 3.0 % efficiency of the control device using ITO and the flexibility of the CNT device is far greater. Finally, we detail an in-depth investigation of the electrical properties of carbon nanotube networks in order to determine and understand the performance limitations. For this, we develop a novel method of atomic force microscope (AFM) scratch lithography in order to isolate individual CNT bundles and a novel method of electric force microscopy (EFM) in order to quantitatively measure local contact resistances on the nanoscale between CNT bundles. We measure bundle-to-bundle junction resistance for a range of bundle diameters which reveals a previously unobserved inverse scaling of contact resistance with diameter. Values range from 1 kOhm to 200 kOhm for bundle diameters typical of CNT TC networks. We also measure the resistivity of ropes of bundles and we find that this resistance is very high and limits the conductivity of the CNT TC films studied in this work. The structure property relationships revealed from these measurements clearly show what type of morphology control is necessary for high performance CNT TCs and that increasing tube length and/or decreasing junction resistance are the primary routes for further increases in performance.
Download or read book Electronic Applications of Single walled Carbon Nanotubes written by Tobias Lockwood and published by . This book was released on 2009 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Applications of Carbon Nanotubes to Flexible Transparent Conductive Electrodes written by Bu-Jong Kim and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Transparent conductive electrodes (TCEs) have attracted great interest because of their wide range of applications in solar cells, liquid crystal displays (LCDs), organic light-emitting diodes (OLEDs), and touch screen panels (TSPs). Indium-tin-oxide (ITO) thin films as TCEs possess exceptional optoelectronic properties, but they have several disadvantages such as a brittle nature due to their low fracture strain and lack of flexibility, a high processing temperature that damages the flexible substrates, low adhesion to polymeric materials, and relative rarity on Earth, which makes their price unstable. This has motivated several research studies of late for developing alternative materials to replace ITO such as metal meshes, metal nanowires, conductive polymers, graphene, and carbon nanotubes (CNTs). Out of the abovementioned candidates, CNTs have advantages in chemical stability, thermal conductivity, mechanical strength, and flexibility. However, there are still several problems yet to be solved for achieving CNT-based flexible TCEs with excellent characteristics and high stability. In this chapter, the properties of CNTs and their applications especially for flexible TCEs are presented, including the preparation details of CNTs based on solution processes, the surface modification of flexible substrates, and the various types of hybrid TCEs based on CNTs.
Download or read book Nanoscale investigation of potential distribution in operating Cu In Ga Se2 thin film solar cells written by Zhenhao Zhang and published by KIT Scientific Publishing. This book was released on 2014-10-16 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: The distribution of the electrostatic potential in and between the materials in Cu(In,Ga)Se2 thin-film solar cells has a major impact on their superior performance. This thesis reported on the nanoscale imaging of the electrostatic potential on untreated cross sections of operating Cu(In,Ga)Se2 solar cells using Kelvin probe force microscopy.
Download or read book Carbon nanotubes and graphene for photonic applications written by L.-M. Peng and published by Elsevier Inc. Chapters. This book was released on 2013-08-31 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon nanotubes (CNTs) are excellent optoelectronic materials and have been investigated for various electronic and optoelectronic device applications, such as light-emitting diodes, photodetectors and photovoltaic cells. This chapter begins with a general discussion on the various types of CNT diodes. It then focuses on a particular type of CNT diode fabricated by a doping-free process, and its application in photovoltaic cells and light-emitting diodes. The chapter ends with an outlook for the use of CNT in further integrated nanoelectronics and optoelectronics.
Download or read book Evolution of Electronic Properties of Cu In Ga Se2 CIGS based Solar Cells During a 3 stage Growth Process written by Jehad A. AbuShama and published by . This book was released on 2003 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Carbon nanotube networks and their application in flexible display technology written by Axel Schindler and published by Cuvillier Verlag. This book was released on 2019-12-19 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the use of carbon nanotubes in form of randomly oriented networks in display technology. Carbon nanotubes can behave either like a metal or like a semiconductor and are used in this work as transparent conductive pixel electrodes as well as semiconducting channel in thin-film transistors. Monte-Carlo simulations examine more closely the percolation probabilities of metallic and semiconducting nanotubes. The experimental part covers methods to create stable surfactant suspensions from nanotube powders, simple and cost-effective low temperature deposition processes from liquid phase on glass and flexible plastic substrates and patterning procedures of the created films. Electrical and optical characterization gives insight on their performance. The realization of liquid crystal and OLED displays shows the compatibility of transparent carbon nanotube electrodes with production processes. Results of the semiconductor application are presented on a transistor level. The dependence of the transistor performance on the network density for both, mixed and highly semiconducting nanotubes is discussed.
Download or read book Relation de Zwischen Den Chur Bayrischen dann den Kays vnnd Fr nckischen Cray Trouppen zu Emhoffen an der Vil vnweit Schmidtm hl in dem Pfaltz Neuburgischen vorgangnen Rencontre written by and published by . This book was released on 1703 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High Performance Carbon Based Optoelectronic Nanodevices written by Yanjie Su and published by Springer Nature. This book was released on 2021-09-15 with total page 199 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on the photoelectric nanodevices based on carbon nanostructures, such as carbon nanotubes, graphene and related heterojunctions. The synthesis of carbon nanostructures and device fabrication are simply given. The interface charge transfer and the performance enhancement in the photodetectors and solar cells are comprehensively introduced. Importantly, carbon allotropes behave as high-mobility conductors or bandgap-tunable semiconductors depending on the atomic arrangements, the direct motivation is to fabricate all-carbon nanodevices using these carbon nanomaterials as building blocks. The photoelectric nanodevices based on all-carbon nanostructures have increasingly attracted attention in the future. The book offers a valuable reference guide to carbon-based photoelectric devices for researchers and graduate school students in the field. It will also benefit all researchers who investigate photoelectric nanodevices and photoelectric conversion with relevant frontier theories and concepts.
Download or read book Study of Single walled Carbon Nanotubes for Applications in Transistors Photodetectors and Stretchable Electrodes for Tactile Sensors written by Steve Park and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Single-walled carbon nanotubes (SWNTs) are tubular carbon-based nanostructures that can be envisioned as graphene rolled up into a seamless cylinder. They are an ideal candidate for use in various electronic and optoelectronic applications due to their unique properties such as high carrier mobility, high light absorption, mechanical flexibility, and solution processability that enable large area, and low cost electronics. Some of the applications include circuits, RFID tags, photodetectors, electronic paper, and robotic systems with skin-like sensing capabilities. To enable these exciting applications, characterization, optimization of device performance, and novel device concepts with properties tailored to specific applications are critical. There are generally two different ways of using SWNTs in electronic devices: 1) as active semiconducting material (in devices like transistors, photodetectors etc.) and 2) as metallic electrodes (as interconnects, electrodes in stretchable tactile sensors etc.). In Chapter I, we will review the recent progress of using SWNTs in both of these applications. Chapter I should equip the reader with a background and understanding of current trends and future outlook of SWNT-based electronics. In Chapter II and Chapter III, we will discuss a novel technique to generate electrical contacts to individual SWNTs, known as dip-pen nanolithography, to characterize their electrical properties. Characterization of electrical properties of individual SWNTs is critical to the understanding of their behavior in large-scale systems. In Chapter II, we will emphasize on the methods and insights to fabricating high quality electrodes with uniform dimensions and functionality. In Chapter III, we will focus on the electrical characterization of individual SWNTs using DPN-fabricated short-channel transistors. Here, we will use our short-channel devices to statistically quantify the percentage of semiconducting versus metallic SWNTs of a solution sorting system, along with critical device parameters such as on-conductance, on/off ratio, and threshold voltage. In Chapter IV, we will move onto discussing large-scale, SWNT film-based transistors. Here, we will introduce a novel technique known as solution shearing to densely align SWNTs over a large area. We will compare aligned SWNT versus randomly oriented SWNTs to elucidate how dense packing and alignment affects the electrical properties of SWNT films. In Chapter V, we will present a hybrid film of SWNT and fullerene as highly sensitive infrared photodetectors. Here, we will discuss how sensitivity can be enhanced using various parameters, and how it can potentially be used in various application such as flexible infrared imaging devices. Finally, in Chapter VI, we will present a stretchable energy harvesting electronic skin device, where SWNTs were used as stretchable electrodes. Here, we will discuss the key concepts in enhancing pressure sensitivity, how to differentiate between different tactile information, and how energy can efficiently be harvested to generate electrical power. Each chapter will conclude with a brief summary, and will discuss the challenges that need to be met to fully realize the potential of SWNTs. This thesis should not only provide new insights to enhancing device performance, but should also excite the reader on the promising outlook of SWNT-based electronics, and motivate them to pursue them.
Download or read book Carbon nanotubes and graphene for photonic applications written by W. Walden-Newman and published by Elsevier Inc. Chapters. This book was released on 2013-08-31 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: Single-walled carbon nanotubes (SWCNTs) have recently attracted tremendous interest as a nanomaterial for photonics and quantum photonics devices. Here we shall review recent work with a focus on quantum light properties such as blinking and spectral diffusion, and in particular, methods and techniques to suppress these detrimental effects with the goal of enhancing optical emission. Furthermore, we shall review recent work on the generation and detection of nonclassical light emissions from individual SWCNTs embedded in polymer cavities, and discuss the role of spatial exciton localization along the tube.
Download or read book Carbon nanotubes and graphene for photonic applications written by W.B. Cho and published by Elsevier Inc. Chapters. This book was released on 2013-08-31 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt: Single-walled carbon nanotubes (SWCNTs) possessing outstanding linear and nonlinear optical properties are utilized as saturable absorbers (SAs) for passive mode-locking of different bulk solid-state lasers in a wide spectral range between 0.8 and 2μm. To overcome some of the limitations and drawbacks of currently available saturable absorbers, diverse carbon nanotubes and techniques for fabrication of single-walled carbon nanotube saturable absorbers (SWCNT-SAs) are investigated. In this chapter, we discuss various manufacturing procedures and essential characteristics of SWCNT-based passive mode-locking devices, and review recent demonstrations of passively mode-locked solid-state lasers employing different types of SWCNT-SAs.
