- The document discusses using a flame synthesis technique called flame stabilization on a rotating surface (FSRS) to produce TiO2 nanoparticles and thin films for use in dye-sensitized solar cells (DSSCs).
- FSRS allows for one-step particle synthesis and film deposition, controlling properties like particle size and crystal phase that impact DSSC efficiency. DSSCs made with FSRS-produced films show efficiencies up to 7.6%.
- Parameters like particle size, crystal phase, thickness, and surface area can be controlled in FSRS and significantly impact DSSC performance. Smaller particles and the anatase crystal phase produce higher photocurrents and efficiencies.
in this ppt it was explained that the importance of dssc and the working principles and the notes during the research work..
the concept was explained in the ppt was very clear......
Basic principle of dye sensitized solar cellLeeya Najwa
The document describes the components and functioning of dye-sensitized solar cells (DSSCs). It lists the typical layers of a DSSC as glass, transparent conducting oxide, TiO2 nanoparticles coated with ruthenium-based dyes, electrolyte, and a counter electrode. The TiO2 provides a large surface area for dye molecules to absorb sunlight. Examples of conducting transparent electrodes are sol-gel processed ZnO and SnO2:F. DSSCs have advantages over silicon solar cells such as lower cost, greater stability, and the ability to achieve efficiencies up to 33% theoretically, although current efficiencies are around 11%.
This document discusses impedance characterization for dye-sensitized solar cells. It first describes the preparation of a standard Grätzel cell, which involves depositing a nanoporous TiO2 layer and dye on a conductive glass substrate. Next, impedance spectroscopy is introduced as a method to characterize and model the cell by measuring its response to alternating currents at different frequencies. Key parameters like series resistance, recombination resistance, and diffusion resistance can be extracted from the impedance spectra and correlated to cell performance at different potentials. The document concludes by mentioning future research directions involving new semiconductor photoelectrodes and solid-state solar cell designs.
Bathochromic shift in photo-absorption spectra of organic dye sensitizers thr...Narges Mohamadi
This document discusses the rational design of new organic dye sensitizers for dye-sensitized solar cells using computational methods. It begins by noting the increasing global energy demand and limitations of current energy sources. It then provides background on dye-sensitized solar cells and their advantages over traditional silicon solar cells. The objectives are to design dyes with broader absorption spectra extending into the near-infrared, reduced HOMO-LUMO gaps, and suitability for solar cells. Several dye structures are computationally modified and evaluated using density functional theory and time-dependent DFT to obtain optical and electronic properties. Promising new dyes with red-shifted absorption are identified.
The document summarizes the key components and operation of dye-sensitized solar cells (DSSCs), also known as Grätzel cells. It describes how DSSCs work by using a sensitizing dye to absorb sunlight and generate excited electrons, which are then injected into a titanium dioxide semiconductor and collected via an electrolyte and cathode. The document also discusses research efforts to improve the efficiency of DSSCs beyond their current maximum of 12% by developing new dyes, electrolytes, and plastic hole conductors.
Dye sensitized solar cells (DSSCs) were invented by Brian O'Regan and Michael Gratzel at UC Berkley as a low-cost alternative to thin film solar cells. DSSCs consist of four main components: a semiconducting electrode like TiO2, a dye sensitizer that absorbs sunlight, a redox mediator like I-/I3- to restore the dye, and a counter electrode. When sunlight is absorbed by the dye, electrons are injected into the conduction band of the oxide and transported through an external circuit to the counter electrode, while the dye is regenerated by the redox mediator. Though less efficient than other solar cells currently, DSSCs offer a cheaper price
Dye-sensitized solar cells (DSSCs) are a type of solar cell that uses dye molecules to absorb sunlight and convert it to electrical energy. They were invented in 1991 by Brian O'Regan and Michael Grätzel. DSSCs consist of a photo-sensitized anode, an electrolyte containing a redox couple, and a cathode. When light is absorbed by the dye, electrons are injected into the conduction band of the semiconductor and transported through the external circuit to be collected at the cathode, while the dye is regenerated through the redox shuttle. DSSCs offer advantages such as low cost, flexibility in design, and the ability to work in low light conditions. Recent research aims to
This document discusses the use of ionic liquids in dye-sensitized solar cells. It begins with an introduction to solar cells and a brief history before explaining the structure and operation of dye-sensitized solar cells. Common components like TiO2 films, dyes, and redox couples are described. The document then notes limitations of traditional liquid electrolytes and proposes ionic liquids as a solution. Several ionic liquids that have been used are listed, along with experimental results showing their effects on performance metrics. The summary concludes by identifying challenges for further developing the use of ionic liquids in dye-sensitized solar cells.
Photosyntheis in a test tube-Dye sensitized solar cells (USPseminar)Atul Raturi
Dye-sensitized solar cells (DSSCs) mimic the process of photosynthesis by using a photosensitive dye to absorb sunlight and a nanocrystalline semiconductor to transport electrons, achieving efficiencies over 10%. DSSCs could provide low-cost solar power for the billions lacking electricity, especially in remote Pacific islands vulnerable to climate change. By emulating natural photosynthesis, DSSCs represent an example of biomimicry and have potential for widespread commercial production of affordable renewable energy.
IBDP Group 4 Project Chemistry:Dye Sensitized Solar Cell (HFS Powai) [Update...Ninad Patil
A Dye Sensitized Solar Cell (DSSC), also known as a Grätzel cell, is a low-cost solar cell that uses dye molecules to convert sunlight into electricity. It consists of a photo-sensitized anode, typically made of titanium dioxide, coated with a dye like pomegranate. An electrolyte fills the space between the anode and a cathode, usually graphite or platinum. When sunlight is absorbed by the dye molecules, electrons are transferred through the titanium dioxide to the anode, creating a current that is collected at the cathode. This current can then be used as a source of electricity.
The document summarizes research on modifying the bandgap of n-TiO2 through carbon doping to enable its use in photoelectrochemical water splitting using visible light. Carbon-modified n-TiO2 (CM-n-TiO2) films were synthesized using spray pyrolysis. Increased carbon doping was achieved by calcining in inert atmosphere. CM-n-TiO2 exhibited photoresponse in the visible spectrum due to carbon doping reducing the bandgap and introducing an intragap band. This modified the band structure of n-TiO2 to extend utilization of solar energy into the visible region.
This document summarizes a presentation on dye sensitized solar cells (DSSC) given by Ashok Kumar Jangid. It describes the basic components and structure of a DSSC, which includes a titanium dioxide semiconductor, sensitizing dye, iodide redox mediator, platinum counter electrode, and glass support. The document explains that light absorption by the dye generates electron injection into the semiconductor to produce a current. Common dyes used include N3, N719, and various ruthenium-based dyes. Potential applications of DSSCs include use in buildings, agriculture, and domestic settings due to their low cost and environmental friendliness.
1) The document summarizes the activities and design project of a student team exploring dye-sensitized solar cells and their potential applications.
2) The team conducted experiments investigating photosynthesis, chromatography of plant pigments, and measuring performance of solar cells.
3) Their design project was to create a product called "D-SOBATT" using henna-dyed solar cells that could store solar energy and charge batteries. Their tests achieved higher voltages than previous studies.
Recent progress in non platinum counter electrode materials for dye sensitize...Science Padayatchi
Dye-sensitized solar cells (DSSCs) have gained increasing attention
with regard to photovoltaic devices, because of their low
cost and simple fabrication methods; they are mostly investigated
in indoor light-harvesting and portable applications. The
focus has been on three main parameters of photovoltaic devices,
that is, lifetime, and cost effectiveness. A DSSC consists of
four prominent components including a photoanode, a photosensitizer,
a redox electrolyte, and a counter electrode. The
counter electrode is a crucial component, in which triiodide is
reduced to iodide by electrons flowing through the external
circuit. An effective approach to improve the performance of
a counter electrode is to enhance the power conversion efficiency
and to reduce the cost of the device. Platinum-coated
conducting glass electrodes give the best performance, but
their high cost and the scarcity of platinum restricts large-scale
application in DSSCs. This has prompted researchers to develop
low-costing platinum-free electrodes for DSSCs. In this
review, we focus mainly on counter electrode materials for the
electrocatalytic redox reaction for the I¢/I¢
3 electrolyte, and
apart from this, other counter electrode materials for iodinefree
redox electrolytes are discussed. Different counter electrode
materials are highlighted in different categories such as
carbon materials, conducting polymers, oxide and sulfide materials,
transition-metal nitrides and carbides, and composite
materials. The stability of counter electrodes in DSSCs is also
presented.
Done By: Arwa_Black7
School Name: Arwa Bint Abdul Motaleb Secondary Independent School for Girls
Dye-Sensitized Solar Cell (DSSC) Module:
The students study the concept of using dyes to plant dyes to capture the solar energy to convert it into electrical energy simulating the natural process “photosynthesis”. They use the workshop-gained knowledge in DSSC to invent new products.
Our project idea is about using of basil pigment in lighting tents in the desert using Dye-sensitized solar cell.
Dye sensitized solar cell using Grape JuiceRavinder Kumar
This presentation has some video too so don't miss than. When you play this presentation on full screen they will play automatically in your computer after download. thank you .
This document summarizes a research paper on dye sensitized solar cells (DSSCs). It provides background on the development of DSSCs since 1991 and their advantages over traditional silicon solar cells in terms of lower cost and simpler preparation. However, liquid electrolytes used in early DSSCs limited long-term performance. Recent research has focused on improving electrolytes, particularly developing quasi-solid state electrolytes, to enhance photoelectric performance and stability for practical applications of DSSCs. The document reviews progress on quasi-solid state electrolytes and their advantages over liquid electrolytes for DSSCs.
This presentation summarizes history and recent development of perovskite solar cells. If you have any questions or comments, you can reach me at agassifeng@gmail.com
Done by Group: Golden
School: Al Wakra Independent School for Girls
Dye-Sensitized Solar Cells (DSSC) Module: The students study the concept of using dyes to plant dyes to capture the solar energy to convert it into electrical energy simulating the natural process “photosynthesis”. They use the workshop-gained knowledge in DSSC to invent new products.
The project consists of two parts, one of them is improving DSSC (They used different dyes) and the other part is an idea about application on the traffic lights.
The document summarizes ongoing research to develop coatings for gravitational wave detectors like Advanced LIGO that minimize thermal noise. Coating thermal noise currently limits detector sensitivity. Research is focused on optimizing coating design and materials like titania-doped tantala to reduce mechanical loss. Experiments aim to better understand dissipation mechanisms to guide further improvements for Advanced LIGO and future detectors. An international collaboration of coating laboratories is working to characterize coatings and identify promising solutions.
The document summarizes ongoing research to develop improved coatings for reducing thermal noise in gravitational wave detectors like Advanced LIGO. Key areas of focus include reducing dissipation in tantala coatings through doping, investigating alternative high index materials, measuring material properties more precisely, and studying approaches for cancelling thermal noise effects through optimized coating designs. Several research groups outlined ongoing experiments and modeling efforts aimed at better understanding coating sources of thermal noise and informing future coating developments for gravitational wave detectors.
Influence of Thickness on Electrical and Structural Properties of Zinc Oxide ...paperpublications3
Abstract: Zinc Oxide (ZnO) thin films were prepared on corning (7059) glass substrates at a thickness of 75.5 and 130.5nm by RF sputtering technique. The deposition was carried out at room temperature after which the samples were annealed in open air at 1500C. The electrical and structural properties of these films were studied. The electrical properties of the films were monitored by four-point probe method while the structural properties were studied by X-ray diffraction (XRD). It was found that the electrical resistance of the films decreases with increase in the thickness of the films. The XRD analysis of the films showed that the films have a peak located at 〖34.31^0-34.35〗^0with hkl (002). Other parameters calculated include the stress ( ) and the grain size (D).
This document discusses the use of positron annihilation spectroscopy to analyze the free volume nanohole distribution in polymers and its correlation to the physico-chemical properties of polymers. It provides background on positron annihilation spectroscopy and how it can be used to measure free volume in polymers. The document then describes several studies that use this technique to analyze the influence of free volume properties on the swelling of polymer hydrogels, structure-property relationships in modified epoxy resins, and free volume and interfacial interactions in epoxy clay composites.
Synthesis and characterisation of k doped zno 1Jeslin Mattam
Thin film technology has been developed for integrated circuits. Thin films are two-dimensional due to their small thickness and need a substrate. They are created through atomic/molecular processes like chemical vapor deposition or physical deposition. Structural properties are analyzed using electron diffraction and electrical properties depend on temperature. Optical measurements determine band structure and lattice vibrations. Applications include drug delivery, optical coatings, transistors, solar cells, and metallurgical coatings. Zinc oxide thin films were synthesized with potassium doping and analyzed. X-ray diffraction showed the films were phase pure wurtzite structure. Resistance decreased and particle size increased with higher doping concentration.
This document summarizes the fabrication of patterned ferromagnetic shape memory thin films. It discusses two routes for micropatterning Ni-Mn-Ga thin films using self-assembled polystyrene spheres and reactive ion etching. Route 1 uses a Si sacrificial layer deposited at 500°C, while Route 2 produces arrays of Ni-Mn-Ga antidots at room temperature followed by annealing at 500°C. Characterization shows the patterned films via Route 2 exhibit ferromagnetism up to 100°C and a spread martensitic transformation, demonstrating their functional properties. Route 1 showed promise but requires further optimization.
This document discusses using functional nanoporous materials for heavy metal sequestration. It describes Self-Assembled Monolayers on Mesoporous Supports (SAMMS) which use high surface area nanoporous substrates coated with tailored organic monolayers for selectively binding heavy metals and radionuclides. SAMMS provides high capacity, fast sorption kinetics, and chemical specificity that can be modified for different targets through the monolayer interface. New classes of functional nanoporous materials like mesoporous metal phosphates and carbons also show promise for heavy metal capture.
This document discusses microfabrication processes used to manufacture microelectromechanical systems (MEMS) and microsystems. It describes that traditional machine tools cannot be used at the microscale, so physical-chemical processes developed for integrated circuits are adopted. Key microfabrication processes discussed include photolithography, ion implantation, diffusion, oxidation, deposition, and etching. Photolithography involves using a photosensitive film and optical image to produce patterns on a substrate. Ion implantation and diffusion are methods for doping silicon substrates with dopants like boron and phosphorus. Fick's laws of diffusion and the diffusion equation are provided to analyze dopant distribution over time.
Dye Sensitized Solar Cells Incorporated with Tio2 -ZnO NanoparticlesScientific Review SR
This document summarizes a study that incorporated zinc oxide (ZnO) nanoparticles into dye-sensitized solar cells (DSSCs) to improve their photovoltaic performance. DSSCs were fabricated with TiO2 films that were coated with different numbers of ZnO layers using successive ionic layer adsorption and reaction (SILAR). The cells were tested under illumination and the best performance was achieved with two SILAR cycles of ZnO, with a power conversion efficiency of 0.0064%, over double that of cells without ZnO. More ZnO layers led to lower efficiencies due to increased recombination and reduced light absorption, showing an optimal thickness was achieved with two SILAR cycles.
In-situ TEM studies of tribo-induced bonding modification in near-frictionles...Deepak Rajput
A presentation on "In-situ TEM studies of tribo-induced bonding modification in near-frictionless carbon films" made by Deepak Rajput. This presentation was based on "critical review of a paper," in All Things Carbon course offered at the University of Tennessee Space Insitute at Tullahoma in Fall 2009.
Rapid reduction of ultrathin films of graphene oxide on large area silicon su...Conference Papers
This document summarizes research on producing graphene oxide thin films on large silicon substrates using ultrasonic spray coating and rapid thermal reduction. GO droplets were spray coated in ethanol and overlapped to form uniform thin films. Films were reduced at 1100°C by rapid thermal processing (RTP), achieving sheet resistances of 1-4 kOhms/sq. Characterization with SEM, AFM, XPS and four-point probe showed the spray coating produced uniform, continuous thin films with increasing thickness for more spray passes. RTP effectively removed oxygen and produced conductive rGO with mostly sp2 bonding, while lower temperature reduction was less effective. Sheet resistance generally decreased with more spray passes due to increased thickness.
Transparent and Conducting TiO2 : Nb Thin Films Prepared by Spray Pyrolysis T...arj_online
1) The document describes a study on preparing transparent and conducting niobium-doped titanium dioxide (TNO) thin films using the spray pyrolysis technique.
2) Undoped and niobium-doped TiO2 films were deposited on glass substrates at 500°C from precursor solutions. Increasing the Nb concentration was found to decrease the film resistivity.
3) The minimum resistivity of 3.36×10-3 Ω cm was obtained for a 2% Nb-doped TiO2 film after annealing in hydrogen at 500°C. X-ray diffraction analysis showed the films had a polycrystalline anatase structure without impurities.
Effect of zinc on structural and some optical properties of cd s thin filmsAlexander Decker
This document summarizes research on the structural and optical properties of cadmium sulfide (CdS) thin films doped with varying concentrations of zinc (Zn). X-ray diffraction analysis showed that all films had a hexagonal structure and were polycrystalline. Grain size decreased with increasing Zn concentration, while surface roughness decreased based on atomic force microscopy. Optical analysis found that transmittance increased with Zn concentration, as did the optical band gap. Increasing the Zn dopant concentration improved some structural and optical properties of the CdS thin films.
This to demonstrate the laser ablation of hard materials to form a thin film for optical sensors. The work was done at DIllard University , New Orleans LA by Professor Abdalla Darwish. any comment e-mail adarwish@bellsouth.net.
This document summarizes research on the structural, optical, and electrical properties of flower-like zinc oxide (ZnO) thin films deposited by chemical bath deposition. X-ray diffraction analysis showed the films had a hexagonal wurtzite crystal structure. The crystallite size increased slightly with higher annealing temperatures from 47.6-50.3 nm. Optical transmission was over 60% in the visible range and bandgap decreased from 3.23 to 3 eV with increasing annealing temperature. Scanning electron microscopy revealed flower-shaped grains several nanometers in size. Electrical conductivity increased with higher annealing temperature as measured by four-probe method.
ACP-Solar_Cell-DSSC.ppt for early resaerMohdQasim53
The document discusses the growth and fabrication of dye sensitized solar cells using multilayer transparent conductive films. It describes:
1. How multilayer transparent conductive oxide (TCO) films like ZnO/Ag/ZnO and Al-ZnO/Ag/Al-ZnO can be used as electrodes in dye sensitized solar cells (DSSCs), providing low sheet resistance and high optical transparency.
2. The fabrication and characterization of ZnO/Ag/ZnO and Al-doped ZnO/Ag/Al-doped ZnO multilayer TCO films for use as electrodes in DSSCs, achieving transmittance over 80% and sheet resistance below 10 ohm/sq.
1) Titania nanopowder was prepared using a sol-gel method with titanium butoxide and nitric acid as precursors and urea as a dopant to decrease the band gap, allowing for visible light absorption.
2) Characterization with XRD, FTIR, UV-Vis, and SEM showed the powders were nanocrystalline with a band gap below 2.5 eV.
3) In photocatalytic tests, the powders significantly degraded xylenes and ethylbenzene (70% and 60% respectively) under visible light, but degraded toluene to a lesser extent (7.44%), demonstrating their photocatalytic activity.
Joam (preparation and characterization of zn o thin films deposited by sol ge...Phaccebookq Nizar
The document summarizes research on preparing and characterizing ZnO thin films deposited using a sol-gel spin coating method. Thermogravimetric analysis showed weight loss in the films continued until 300°C. X-ray diffraction revealed the films had a hexagonal wurtzite crystal structure and were preferentially oriented along the c-axis. Higher spin coating speeds resulted in smaller grain sizes and higher dislocation densities. Optical analysis found the films were highly transparent in the visible range and had direct band gaps between 3.28-3.29 eV that increased slightly with higher spin speeds.
Morphologies of c-si Solar cell - Targeting the approach with least light ref...JATIN KUMAR
As the Reflection of Sunlight, falling on the solar cells is an big issue for its performance, this presentation deals with some Morphologies, mostly used these days in industries and some others also which was in trend years before, for c-Si cells.
The objective is to find out the most appropriate technology for Surface texturing either with or without AR coating that can reduce reflection to its minimum possible value.
Although, it is understood that, with best technology, cost also increases. Therefore, it is a quite challenging task at the present time to provide a cost effective surface Morphologies to limit the Panel cost to not to rise much.
BLOCKCHAIN TECHNOLOGY - Advantages and DisadvantagesSAI KAILASH R
Explore the advantages and disadvantages of blockchain technology in this comprehensive SlideShare presentation. Blockchain, the backbone of cryptocurrencies like Bitcoin, is revolutionizing various industries by offering enhanced security, transparency, and efficiency. However, it also comes with challenges such as scalability issues and energy consumption. This presentation provides an in-depth analysis of the key benefits and drawbacks of blockchain, helping you understand its potential impact on the future of technology and business.
Vulnerability Management: A Comprehensive OverviewSteven Carlson
This talk will break down a modern approach to vulnerability management. The main focus is to find the root cause of software risk that may expose your organization to reputation damage. The presentation will be broken down into 3 main area, potential risk, occurrence, and exploitable risk. Each segment will help professionals understand why vulnerability management programs are so important.
How UiPath Discovery Suite supports identification of Agentic Process Automat...DianaGray10
📚 Understand the basics of the newly persona-based LLM-powered Agentic Process Automation and discover how existing UiPath Discovery Suite products like Communication Mining, Process Mining, and Task Mining can be leveraged to identify APA candidates.
Topics Covered:
💡 Idea Behind APA: Explore the innovative concept of Agentic Process Automation and its significance in modern workflows.
🔄 How APA is Different from RPA: Learn the key differences between Agentic Process Automation and Robotic Process Automation.
🚀 Discover the Advantages of APA: Uncover the unique benefits of implementing APA in your organization.
🔍 Identifying APA Candidates with UiPath Discovery Products: See how UiPath's Communication Mining, Process Mining, and Task Mining tools can help pinpoint potential APA candidates.
🔮 Discussion on Expected Future Impacts: Engage in a discussion on the potential future impacts of APA on various industries and business processes.
Enhance your knowledge on the forefront of automation technology and stay ahead with Agentic Process Automation. 🧠💼✨
Speakers:
Arun Kumar Asokan, Delivery Director (US) @ qBotica and UiPath MVP
Naveen Chatlapalli, Solution Architect @ Ashling Partners and UiPath MVP
Uncharted Together- Navigating AI's New Frontiers in LibrariesBrian Pichman
Journey into the heart of innovation where the collaborative spirit between information professionals, technologists, and researchers illuminates the path forward through AI's uncharted territories. This opening keynote celebrates the unique potential of special libraries to spearhead AI-driven transformations. Join Brian Pichman as we saddle up to ride into the history of Artificial Intelligence, how its evolved over the years, and how its transforming today's frontiers. We will explore a variety of tools and strategies that leverage AI including some new ideas that may enhance cataloging, unlock personalized user experiences, or pioneer new ways to access specialized research. As with any frontier exploration, we will confront shared ethical challenges and explore how joint efforts can not only navigate but also shape AI's impact on equitable access and information integrity in special libraries. For the remainder of the conference, we will equip you with a "digital compass" where you can submit ideas and thoughts of what you've learned in sessions for a final reveal in the closing keynote.
Finetuning GenAI For Hacking and DefendingPriyanka Aash
Generative AI, particularly through the lens of large language models (LLMs), represents a transformative leap in artificial intelligence. With advancements that have fundamentally altered our approach to AI, understanding and leveraging these technologies is crucial for innovators and practitioners alike. This comprehensive exploration delves into the intricacies of GenAI, from its foundational principles and historical evolution to its practical applications in security and beyond.
EuroPython 2024 - Streamlining Testing in a Large Python CodebaseJimmy Lai
Maintaining code quality through effective testing becomes increasingly challenging as codebases expand and developer teams grow. In our rapidly expanding codebase, we encountered common obstacles such as increasing test suite execution time, slow test coverage reporting and delayed test startup. By leveraging innovative strategies using open-source tools, we achieved remarkable enhancements in testing efficiency and code quality.
As a result, in the past year, our test case volume increased by 8000, test coverage was elevated to 85%, and Continuous Integration (CI) test duration was maintained under 15 minute
The Zaitechno Handheld Raman Spectrometer is a powerful and portable tool for rapid, non-destructive chemical analysis. It utilizes Raman spectroscopy, a technique that analyzes the vibrational fingerprint of molecules to identify their chemical composition. This handheld instrument allows for on-site analysis of materials, making it ideal for a variety of applications, including:
Material identification: Identify unknown materials, minerals, and contaminants.
Quality control: Ensure the quality and consistency of raw materials and finished products.
Pharmaceutical analysis: Verify the identity and purity of pharmaceutical compounds.
Food safety testing: Detect contaminants and adulterants in food products.
Field analysis: Analyze materials in the field, such as during environmental monitoring or forensic investigations.
The Zaitechno Handheld Raman Spectrometer is easy to use and features a user-friendly interface. It is compact and lightweight, making it ideal for field applications. With its rapid analysis capabilities, the Zaitechno Handheld Raman Spectrometer can help you improve efficiency and productivity in your research or quality control workflows.
Mastering OnlyFans Clone App Development: Key Strategies for SuccessDavid Wilson
Dive into the critical elements of OnlyFans clone app development, from understanding user needs and designing engaging platforms to implementing robust monetization strategies and ensuring scalability. Discover how RichestSoft can guide you through the development process, offering expert insights and proven strategies to help you succeed in the competitive market of content monetization.
Improving Learning Content Efficiency with Reusable Learning ContentEnterprise Knowledge
Enterprise Knowledge’s Emily Crockett, Content Engineering Consultant, presented “Improve Learning Content Efficiency with Reusable Learning Content” at the Learning Ideas conference on June 13th, 2024.
This presentation explored the basics of reusable learning content, including the types of reuse and the key benefits of reuse such as improved content maintenance efficiency, reduced organizational risk, and scalable differentiated instruction & personalization. After this primer on reuse, Crockett laid out the basic steps to start building reusable learning content alongside a real-life example and the technology stack needed to support dynamic content. Key objectives included:
- Be able to explain the difference between reusable learning content and duplicate content
- Explore how a well-designed learning content model can reduce duplicate content and improve your team’s efficiency
- Identify key tasks and steps in creating a learning content model
MAKE MONEY ONLINE Unlock Your Income Potential Today.pptxjanagijoythi
In today's digital age, the internet offers unparalleled opportunities to
generate income and build financial independence from the comfort of
your home or anywhere with an internet connection. Whether you're a
student looking to earn extra cash, a stay-at-home parent seeking
flexible work options, or a professional aiming to diversify your income
streams, this book is your comprehensive guide to navigating the vast
landscape of online earning.
Step-By-Step Process to Develop a Mobile App From Scratchsoftsuave
Learn the step-by-step process to develop a mobile app from scratch with our detailed guide. Discover essential steps, tools, and tips on how to build an app from scratch. Read more blogs at Soft Suave.
more: https://www.softsuave.com/blog/develop-a-mobile-app-from-scratch/
Use Cases & Benefits of RPA in Manufacturing in 2024.pptxSynapseIndia
SynapseIndia offers top-tier RPA software for the manufacturing industry, designed to automate workflows, enhance precision, and boost productivity. Experience the benefits of advanced robotic process automation in your manufacturing operations.
Retrieval Augmented Generation Evaluation with RagasZilliz
Retrieval Augmented Generation (RAG) enhances chatbots by incorporating custom data in the prompt. Using large language models (LLMs) as judge has gained prominence in modern RAG systems. This talk will demo Ragas, an open-source automation tool for RAG evaluations. Christy will talk about and demo evaluating a RAG pipeline using Milvus and RAG metrics like context F1-score and answer correctness.
Types of Weaving loom machine & it's technologyldtexsolbl
Welcome to the presentation on the types of weaving loom machines, brought to you by LD Texsol, a leading manufacturer of electronic Jacquard machines. Weaving looms are pivotal in textile production, enabling the interlacing of warp and weft threads to create diverse fabrics. Our exploration begins with traditional handlooms, which have been in use since ancient times, preserving artisanal craftsmanship. We then move to frame and pit looms, simple yet effective tools for small-scale and traditional weaving.
Advancing to modern industrial applications, we discuss power looms, the backbone of high-speed textile manufacturing. These looms, integral to LD Texsol's product range, offer unmatched productivity and consistent quality, essential for large-scale apparel, home textiles, and technical fabrics. Rapier looms, another modern marvel, use rapier rods for versatile and rapid weaving of complex patterns.
Next, we explore air and water jet looms, known for their efficiency in lightweight fabric production. LD Texsol's state-of-the-art electronic Jacquard machines exemplify technological advancements, enabling intricate designs and patterns with precision control. Lastly, we examine dobby looms, ideal for medium-complexity patterns and versatile fabric production.
This presentation will deepen your understanding of weaving looms, their applications, and the innovations LD Texsol brings to the textile industry. Join us as we weave through the history, technology, and future of textile production. Visit our website www.ldtexsol.com for more information.
Garbage In, Garbage Out: Why poor data curation is killing your AI models (an...Zilliz
Enterprises have traditionally prioritized data quantity, assuming more is better for AI performance. However, a new reality is setting in: high-quality data, not just volume, is the key. This shift exposes a critical gap – many organizations struggle to understand their existing data and lack effective curation strategies and tools. This talk dives into these data challenges and explores the methods of automating data curation.
Redefining Cybersecurity with AI CapabilitiesPriyanka Aash
In this comprehensive overview of Cisco's latest innovations in cybersecurity, the focus is squarely on resilience and adaptation in the face of evolving threats. The discussion covers the imperative of tackling Mal information, the increasing sophistication of insider attacks, and the expanding attack surfaces in a hybrid work environment. Emphasizing a shift towards integrated platforms over fragmented tools, Cisco introduces its Security Cloud, designed to provide end-to-end visibility and robust protection across user interactions, cloud environments, and breaches. AI emerges as a pivotal tool, from enhancing user experiences to predicting and defending against cyber threats. The blog underscores Cisco's commitment to simplifying security stacks while ensuring efficacy and economic feasibility, making a compelling case for their platform approach in safeguarding digital landscapes.
1. Flame Synthesis of TiO 2 Nanoparticles and Their Application in Dye Sensitized Solar Cells Saro Memarzadeh Department of Aerospace and Mechanical Engineering University of Southern California Qualifying Examination May 20, 2010
2. Work Published/Submitted Memarzadeh, S., Tolmachoff, E., Phares, D. J., Wang, H.,“ Properties of Nanocrystalline TiO2 Thin Films Synthesized by Flat Flame Stabilized on a Rotating Surface ”, Proceedings of the Combustion Institute , submitted, 2010. Memarzadeh, S. ,“Mesoporous TiO2 Thin Films Prepared by Flame Stabilized on a Rotating Surface --Application to Dye Sensitized Solar Cells”, presented in 9 th US national meeting of the Combustion Institute, 2009
3. Outline Introduction Flame Stabilized on a Rotating Surface (FSRS) Study on particle and film properties made by FSRS Study on the DSSC characteristics of cells made from FSRS anodes Future Work
4. Introduction Photo-Electrochemical Cells 1839. Edmond Becquerel Silver halide salt solution with two electrodes merged in it 1873. Herman Vogel Extended the photo-response of Silver Halides by adding small amounts of an Aniline based dye 1887. James Moser First dye sensitized solar cell using Erythrosine 1964. Hishiki and Namba Used dye sensitization on metal oxides (ZnO) Discovered a monolayer is the most efficient
5. Introduction Fundamental Problem: Limited light-capture cross-section of the dye molecule The area the sensitizer molecule occupies (S) is 1 to 2 nm 2 At most 8% of the available surface area is getting used! Solution: Use of high surface area mesoporous films † Hagfeldt A., Acc. Chem. Res., 2000, 33 (5), pp 269–277
6. Introduction Dye Sensitized Solar Cells (DSSC) using a meso-porous anode Invented by M. Gratzel and B. O’Regan in 1991 S electrolyte TCO TCO dye TiO 2 e - HOMO LUMO S* h ox (I 3 - ) red (I - ) Redox mediator e - e - -0.5 0.0 0.5 1.0 E (V) maximum Voltage ~0.75 V h 10-15 m 10-20 m
8. Parameters affecting the efficiency For many years the research was focused on the dye molecule BUT Film Thickness, size and crystallinity of TiO2 particles and surface area are very important. Michael Gratzel Electrochemistry Communications 11 (2009) 909–912
9. Parameters affecting the efficiency Photovoltage Redox potential of the electrolyte Fermi level of the TiO 2 Electron density in the TiO 2 Photocurrent Charge generation and injection from the dye molecule Number of dye molecules Surface Area Porosity Particle size Film thickness Number of electrons collected at the TCO Charge diffusion And collection
10. Anode characteristics 50 nm Transparent Conductive Glass 10 m thick film of TiO 2 Single crystal Particles Phase pure anatase Thickness of ~10 m Large surface area for dye absorption High electron diffusivity Synthesis Routes Laser ablation Spray pyrolysis Chemical vapor deposition Flame Sol/Gel
11. Sol-Gel method Sol-Gel is the most commonly used method for particle synthesis Easy to control particle size Ability to make very small < 5nm particles Narrow particle size distribution Ability to control film porosity but Slow - low throughput Amorphous particles must be treated Costly cleaning process “ For the best performing TiO 2 electrodes, the synthesis of TiO 2 paste involves hydrolysis of Ti(OCH(CH 3 ) 2 ) 4 in water to ethanol by three times centrifugation. Finally, the ethanol is exchanged with -terpineol by sonication and evaporation. Totally, it takes 3 days . Such a long time procedure of TiO2 paste is economically unsuitable for industrial production and has to be reduced . ” Michael Gratzel Progress in Photovolt: Res. Appl. 2007; 15:603-612
12. A method of one-step particle synthesis/film processing Aerodynamically shaped nozzle ( D = 1 cm) Nozzle-to-disc distance ( L = 3.0 cm) Diameter of rotating disc 30.5 cm (0 to 600 RPM) Observed flame diameter ~ 3 cm Flame-to-disc distance 0.29±0.03 cm Flame Stabilized on Rotating Surface (FSRS) Tolmachoff et al., Proceedings of the Combustion Institute 32 (2009) 1839–1845
13. TTIP Meso-porous film TiO 2 Vapor Nanoparticles Decomposition & oxidation Nucleation, coagulation Flame Stabilized on Rotating Surface ~2100 K 400 K 400 K 0.29±0.03 cm
14. Flame Structure (Ethylene-oxygen-argon, = 0.4) Computations used the Sandia counterflow flame code and USC Mech II 10 -4 10 -3 10 -2 10 -1 10 0 2.7 2.8 2.9 3.0 3.1 3.2 3.3 Mole Fraction O 2 C 2 H 4 H H 2 CO H 2 O CO 2 Distance from the Nozzle, x (cm) 500 1000 1500 2000 2500 Stagnation surface T (K) Particle nucleation/ growth region 0 100 200 300 400 500 Axial Velocity v (cm/s) Laminar flame speed Particle nucleation/ growth region
15. FSRS Properties Sol-Gel Method 12 m TiO 2 film 11 % photoefficiency @ AM1.5 FSRS Method allows for: Particle synthesis and film deposition in one step Particles are Anatase How would meso-porous thin films made using FSRS technique would perform in a DSSC ? FSRS Method 6 m TiO 2 film 7.6 % photoefficiency @ AM1.5 Gratzel M., Journal of Photochemistry and Photobiology A: Chemistry 164 (2004) 3-14 To what degree and how can these parameters be controlled in FSRS?
16. To what degree and how can these parameters be controlled in FSRS? Michael Gratzel Electrochemistry Communications 11 (2009) 909–912
18. Particle and Film Morphology 10 nm rad = 300 RPM 3400 PPM TTIP 1070 PPM TTIP 5660 PPM TTIP Particles Mostly Spherical Mostly single crystals Occasionally sintered Film Typically 5 m/min Net deposition rate = ~ 1 m/sec Film is highly porous but uniform Film thickness in FSRS is controlled by the total amount of the injected precursor 5 minute 14 m
20. Particle Characterization: Diameter Flames 1a, 1b and 1c pre-injection composition 4%C2H4-26.5%O2-Ar, Phi = 0.45 Higher injection rates lead to larger particle sizes Particle size in FSRS is independent of the Equivalence ratio 60.0 36.6 11.2 TTIP (ml/hr) 1c 1b 1a Flame No. 1.27 11.2 4a 1.14 11.2 3a 0.52 11.2 1a Phi TTIP (ml/hr) Flame No.
21. = 0 RPM Particle size can be controlled using precursor injection rate and the distributions are similar to the Sol-Gel method Particle Characterization: Diameter Gratzel M., Journal of Photochemistry and Photobiology A: Chemistry 164 (2004) 3-14
22. Crystal Phase Lean flames favor formation of Anatase Rich flames (Oxygen deficient) produce mostly Rutile Crystal Phase can be controlled 1.27 11.2 4a 1.14 11.2 3a 0.52 11.2 1a Phi TTIP (ml/hr) Flame No.
23.
24. Particle Characterization: Band Edge The band edge of the particles are independent of flame stoichiometry Particle size affects the band edge TAUC Plot for indirect bandgap semiconductor (TiO 2 ) 1.27 11.2 4a 1.14 11.2 3a 0.52 11.2 1a Phi TTIP (ml/hr) Flame No. 60.0 36.6 11.2 TTIP (ml/hr) 1c 1b 1a Flame No. 0.86 0.70 0.52 Phi
25. FSRS and DSSC fabrication FSRS has the potential of fabrication of an efficient Electron transport media by Combining particle synthesis and film deposition in a single step Tuning particle size Controlling crystal phase of the particles Tuning absorption band edge of the particles Controlling film thickness How do these parameters affect the efficiency of a DSSC? Fabrication Steps Particle synthesis and film deposition Densification Sintering Staining with the dye Counter Electrode preparation (doctor blading of platinum paste) Cell Assembly (Electrolyte filling, sealing)
27. Post-Deposition Treatment Densification and Sintering Improve mechanical integrity Create interparticle necking , BUT Reduce surface area Anodes FSRS method Densified using ethanol droplets Thickness 3 m
28. Effect of Particle Size (3 m cells) Small particles -> Larger surface areas -> Better light absorption -> high closed-circuit current (better photoefficiency). Current density can be more than doubled by controlling particle size
29. Effect of Particle Size (3 m cells) Particle size has a substantial effect on short circuit current at light intensities above 500 W/m 2 Open circuit voltage stays relatively constant at close to AM 1.5 intensities
30. TiO 2 layer thickness effect Nazeeruddin M. K., J. Am. Chem. Soc., 1993, 115 (14), pp 6382–6390
31. Effect of Crystal Phase Anatase performs better due to more absorption of the dye 1.27 11.2 4a 0.52 11.2 1a Phi TTIP (ml/hr) Flame No.
32. Concluding Remarks FSRS can provide a way to control particle and film properties that substantially affect DSSC efficiency FSRS can reduce fabrication time by about a third The anodes made with FSRS technique show similar properties and characteristics in a DSSC compared to the Sol-Gel method anodes High efficiency cells have been achieved BUT Reproducibility is an issue !
33. Current Status Reproducible current densities of 12 mA/cm2 have been achieved These cells typically show 5 to 6 % efficiency Under similar conditions: Thickness 12 m No anti-reflection layer No additional treatment Same TCO, electrolyte and dye Ito S. et al.,Thin Solid Films 516 (2008) 4613–4619
35. Summary The effect of FSRS fabrication parameters on the particle and film properties The effect of these parameters on DSSC efficiency have been studied In the process of identifying reproducibility issues and removing them Develop a model which directly correlates FSRS parameters and Cell Efficiency Exploring other potentials of FSRS method Example: Multi-Layer architectures Developing a fundamental model of DSSC to help in understanding fundamental parameters Example: Diffusivity
36. Electron Transport: Theory I-V curve can be predicted by modeling electron density variations in the film n c total number of electrons in the conduction band n t total number of electrons in the trap states n d total number of electrons in the conduction band in the dark K trap trapping rate constant K rec recombination rate constant with the electrolyte K tv recombination rate constant with the valence band D Electron diffusion coefficient G Electron Generation L Electron Loss
37. Electron Transport: Experiments Open Circuit Voltage Decay Charge extraction Electrochemical Impedance Spectroscopy Bailes M. et al.,J. Phys. Chem. B 2005, 109, 15429 15435
38. Multi-layered Architecture FSRS can produce multi-layer architectures Front layer: small particles (<10 nm) to maximize surface area and adhesion Back layer: Larger particles (~20 nm) to create electron density gradient and facilitate electrolyte transport Light Scattering layer Bi-layer films have shown promise The bi-layer was prepared by the FSRS process using a TTIP precursor injection rate of 11.2 ml/hr for 2 minutes followed by 36.6 ml/hr of injection rate.