Science Current Events | Science News | Brightsurf.com
 

New Material Promises Better Solar Cells

February 13, 2013
Researchers at the Vienna University of Technology show that a recently discovered class of materials can be used to create a new kind of solar cell.

Single atomic layers are combined to create novel materials with completely new properties. Layered oxide heterostructures are a new class of materials, which has attracted a great deal of attention among materials scientists in the last few years. A research team at the Vienna University of Technology, together with colleagues from the USA and Germany, has now shown that these heterostructures can be used to create a new kind of extremely efficient ultra-thin solar cells.

Discovering New Material Properties in Computer Simulations

"Single atomic layers of different oxides are stacked, creating a material with electronic properties which are vastly different from the properties the individual oxides have on their own", says Professor Karsten Held from the Institute for Solid State Physics, Vienna University of Technology. In order to design new materials with exactly the right physical properties, the structures were studied in large-scale computer simulations. As a result of this research, the scientists at TU Vienna discovered that the oxide heterostructures hold great potential for building solar cells.

Turning Light into Electricity

The basic idea behind solar cells is the photoelectric effect. Its simplest version was already explained by Albert Einstein in 1905: when a photon is absorbed, it can cause an electron to leave its place and electric current starts to flow. When an electron is removed, a positively charged region stays behind - a so called "hole". Both the negatively charged electrons as well as the holes contribute to the electrical current.

"If these electrons and holes in the solar cell recombine instead of being transported away, nothing happens and the energy cannot be used", says Elias Assmann, who carried out a major part of the computer simulations at TU Vienna. "The crucial advantage of the new material is that on a microscopic scale, there is an electric field inside the material, which separates electrons and holes." This increases the efficiency of the solar cell.

Two Isolators Make a Metal

The oxides used to create the material are actually isolators. However, if two appropriate types of isolators are stacked, an astonishing effect can be observed: the surfaces of the material become metallic and conduct electrical current. "For us, this is very important. This effect allows us to conveniently extract the charge carriers and create an electrical circuit", says Karsten Held. Conventional solar cells made of silicon require metal wires on their surface to collect the charge carriers - but these wires block part of the light from entering the solar cell.

Not all photons are converted into electrical current with the same efficiency. For different colors of light, different materials work best. "The oxide heterostructures can be tuned by choosing exactly the right chemical elements", says Professor Blaha (TU Vienna). In the computer simulations, oxides containing Lanthanum and Vanadium were studied, because that way the materials operate especially well with the natural light of the sun. "It is even possible to combine different kinds of materials, so that different colors of light can be absorbed in different layers of the solar cell at maximum efficiency", says Elias Assmann.

Putting Theory into Practice

The team from TU Vienna was assisted by Satoshi Okamoto (Oak Ridge National Laboratory, Tennessee, USA) and Professor Giorgio Sangiovanni, a former employee of TU Vienna, who is now working at Würzburg University, Germany. In Würzburg, the new solar cells will now be build and tested. "The production of these solar cells made of oxide layers is more complicated than making standard silicon solar cells. But wherever extremely high efficiency or minimum thickness is required, the new structures should be able to replace silicon cells", Karsten Held believes.


Vienna University of Technology


Related Solar Cells Current Events and Solar Cells News Articles


Novel plasma diagnostics method
Could the mundane action of switching on an energy saving light bulb still hold secrets? It does, at least for physicists.

New 'cool roof time machine' will accelerate cool roof deployment
Cool roofs can help keep buildings cool, thus lowering the building's energy use, while also mitigating the urban heat island effect by reflecting sunlight away from buildings and cities. But as cool roofs age and get soiled, how much of their reflectance do they lose?

Graphene pushes the speed limit of light-to-electricity conversion
The efficient conversion of light into electricity plays a crucial role in many technologies, ranging from cameras to solar cells. It also forms an essential step in data communication applications, since it allows for information carried by light to be converted into electrical information that can be processed in electrical circuits.

Solution-grown nanowires make the best lasers
Take a material that is a focus of interest in the quest for advanced solar cells. Discover a "freshman chemistry level" technique for growing that material into high-efficiency, ultra-small lasers.

New ways to see light and store information
Silicon based chips and transistors have been at the heart of all electronic devices since the 1950s. Driven by economic and environmental factors, and by the need for renewable energy resources, there is currently an enormous scientific and technological interest in transitioning away from silicon based electronics to new organic electronic devices.

Researchers create first metal-free catalyst for rechargeable zinc-air batteries
Researchers from Case Western Reserve University and the University of North Texas have made what they believe is the first metal-free bifunctional electrocatalyst that performs as well or better than most metal and metal oxide electrodes in zinc-air batteries.

University of Houston researchers discover N-type polymer for fast organic battery
Researchers at the University of Houston have reported developing an efficient conductive electron-transporting polymer, a long-missing puzzle piece that will allow ultrafast battery applications.

Solving molybdenum disulfide's 'thin' problem
The promising new material molybdenum disulfide (MoS2) has an inherent issue that's steeped in irony. The material's greatest asset--its monolayer thickness--is also its biggest challenge.

Caltech scientists develop cool process to make better graphene
A new technique invented at Caltech to produce graphene--a material made up of an atom-thick layer of carbon--at room temperature could help pave the way for commercially feasible graphene-based solar cells and light-emitting diodes, large-panel displays, and flexible electronics.

Scientists move closer to '2 for 1 deal' on solar cell efficiency
The underlying mechanism behind an enigmatic process called "singlet exciton fission", which could enable the development of significantly more powerful solar cells, has been identified by scientists in a new study.
More Solar Cells Current Events and Solar Cells News Articles

Build Your Own Solar Panel: Generate Electricity from the Sun.

Build Your Own Solar Panel: Generate Electricity from the Sun.
by Phillip Hurley (Author)


Whether you're trying to get off the grid, or you just like to experiment, Build Your Own Solar Panel has all the information you need to build your own photovoltaic panel to generate electricity from the sun. Now available for the first time in print, this revised and expanded edition has easy-to-follow directions, and over 150 detailed photos and illustrations. Lists of materials, tools, and suppliers of PV cells are included. Every-day tools are all that you need to complete these projects.
Build Your Own Solar Panel will show you how to:
Design and build PV panels,
Customize panel output,
Make tab and bus ribbon,
Solder cell connections,
Wire a photovoltaic panel,
Purchase solar cells,
Test and rate PV cells,
Repair damaged solar cells,
Work...

The Physics of Solar Cells (Properties of Semiconductor Materials)

The Physics of Solar Cells (Properties of Semiconductor Materials)
by Jenny Nelson (Author)


This book provides a comprehensive introduction to the physics of the photovoltaic cell. It is suitable for undergraduates, graduate students, and researchers new to the field. It covers: basic physics of semiconductors in photovoltaic devices; physical models of solar cell operation; characteristics and design of common types of solar cell; and approaches to increasing solar cell efficiency. The text explains the terms and concepts of solar cell device physics and shows the reader how to formulate and solve relevant physical problems. Exercises and worked solutions are included. Contents: Photons In, Electrons Out: Basic Principles of PV; Electrons and Holes in Semiconductors; Generation and Recombination; Junctions; Analysis of the p n Junction; Monocrystalline Solar Cells; Thin Film...

Physics of Solar Cells: From Basic Principles to Advanced Concepts

Physics of Solar Cells: From Basic Principles to Advanced Concepts
by Peter Würfel (Author)


Based on the highly regarded and extremely successful first edition, this thoroughly revised, updated and expanded edition contains the latest knowledge on the mechanisms of solar energy conversion.
The textbook describes in detail all aspects of solar cell function, the physics behind every single step, as well as all the issues to be considered when improving solar cells and their efficiency.
Requiring no more than standard physics knowledge, the book enables both students and researchers to understand the factors driving conversion efficiency and to apply this knowledge to their own solar cell development.
New exercises after each chapter help students to consolidate their freshly acquired knowledge, while the book also serves as a reference for researchers already working...

Solar Electricity Handbook - 2013 Edition: A Simple Practical Guide to Solar Energy - Designing and Installing Photovoltaic Solar Electric Systems

Solar Electricity Handbook - 2013 Edition: A Simple Practical Guide to Solar Energy - Designing and Installing Photovoltaic Solar Electric Systems
by Mr Michael Boxwell (Author)


The 2013 edition of the Solar Electricity Handbook is a practical and straightforward guide to using photovoltaic solar panels to generate electricity. It is the seventh edition of the book, which has been updated yearly since 2009.

Assuming no previous knowledge of solar panels, the book explains how solar panels work, how they can be used and explains the steps you need to take to successfully design and install a solar electric system from scratch using photovoltaic solar panels.Accompanying this book is a solar resource website containing lots of useful information, lists of suppliers and on-line solar energy calculators that will simplify the cost analysis and design processes.

Why buy the Solar Electricity Handbook?
The Handbook is a simple, practical guide to using...

Build A Solar Hydrogen Fuel Cell System

Build A Solar Hydrogen Fuel Cell System
by Phillip Hurley (Author)


Learn how to construct and operate the components of a solar hydrogen fuel cell system: the fuel cell stack, the electrolyzer to generate hydrogen fuel, simple hydrogen storage, and solar panels designed specifically to run electrolyzers for hydrogen production. Complete, clear, illustrated instructions to build all the major components make it easy for the non-engineer to understand and work with this important new technology. Featured are the author's innovative and practical designs for efficient solar powered hydrogen production including: ESPMs (Electrolyzer Specific Photovoltaic Modules) – 40 watt solar panels designed specifically to run electrolyzers efficiently; a 40-80 watt electrolyzer for intermittant power from renewable energy sources such as solar and wind; and, a 6-12...

Solar II: How to Design, Build and Set Up Photovoltaic Components and Solar Electric Systems

Solar II: How to Design, Build and Set Up Photovoltaic Components and Solar Electric Systems
by Phillip Hurley (Author)


Now that you've built your solar panels, how do you set up a photovoltaic system and plug in? In Solar II, Phillip Hurley, author of Build Your Own Solar Panel, will show you how to:
Calculate daily electrical usage and needs
Plan and size your solar electric system
Build racks and charge controllers
Mount and orient PV panels
Wire solar panel arrays
Make a ventilated battery box
Wire battery arrays for solar panels
Install an inverter
Maintain solar batteries for optimum life and performance
Make your own combiner box, bus bars, and DC and AC service boxes
Solar II includes easy-to-follow directions with over 150 black & white photos, illustrations and schematics.

Solar Electricity Handbook - 2015 Edition: A simple, practical guide to solar energy - designing and installing solar PV systems.

Solar Electricity Handbook - 2015 Edition: A simple, practical guide to solar energy - designing and installing solar PV systems.
by Michael Boxwell (Author)


The Solar Electricity Handbook - 2015 Edition, is a simple, practical guide to using electric solar panels and designing and installing photovoltaic PV systems. Now in its ninth edition, the book assumes no previous knowledge of solar electric systems. The book explains how solar panels work and how they can be used. It explains the advantages of solar energy and the drawbacks that you need to take into account when designing a solar power system. As well as explaining the underlying principles, it provides a step-by-step guide so that you can successfully design and install a photovoltaic solar system from scratch. Unlike many guides, The Solar Electricity Handbook explains the principles behind the technology, allowing the reader to design solar energy systems with confidence. The book...

Photon Management in Solar Cells

Photon Management in Solar Cells
by Ralf B. Wehrspohn (Editor), Uwe Rau (Editor), Andreas Gombert (Editor)


Written by renowned experts in the field of photon management in solar cells, this one-stop reference gives an introduction to the physics of light management in solar cells, and discusses the different concepts and methods of applying photon management.
The authors cover the physics, principles, concepts, technologies, and methods used, explaining how to increase the efficiency of solar cells by splitting or modifying the solar spectrum before they absorb the sunlight. In so doing, they present novel concepts and materials allowing for the cheaper, more flexible manufacture of solar cells and systems.
For educational purposes, the authors have split the reasons for photon management into spatial and spectral light management.
Bridging the gap between the photonics and the...

Solar Cell & Energy Guide

Solar Cell & Energy Guide
by Silicon Solar


Solar Cell Book

The solar cell book is an information packet on the basics of solar energy. The topics that are covered in the solar cell book are vast but brief. There is just enough information to help you understand how solar cells and solar power work in order to fully understand how everything works you’d need a lot bigger book. There is also information on interconnecting solar cells along with various diagrams that help you understand the ins and outs of solar cells. There is also a class project section with various degrees of difficulty that range from elementary to intermediate levels.

Topics Covered:

PV Terminology
Solar Cell
PV Modules
PV Array
Peak Watt (Wp)
Diamond Solar Cells
Interconnecting Solar Cells
Solar Cells, Second Edition: Materials, Manufacture and Operation

Solar Cells, Second Edition: Materials, Manufacture and Operation
by Augustin McEvoy (Author), L. Castaner (Author), Tom Markvart (Author)


Enormous leaps forward in the efficiency and the economy of solar cells are being made at a furious pace. New materials and manufacturing processes have opened up new realms of possibility for the application of solar cells. Crystalline silicon cells are increasingly making way for thin film cells, which are spawning experimentation with third-generation high-efficiency multijunction cells, carbon-nanotube based cells, UV light for voltage enhancement, and the use of the infrared spectrum for night-time operation, to name only a few recent advances. This thoroughly updated new edition of Markvart and Castaner's Solar Cells, extracted from their industry standard Practical Handbook of Photovoltaics, is the definitive reference covering the science and operation, materials and manufacture...

© 2015 BrightSurf.com