Thursday, December 22, 2011
What is nano?
Wednesday, September 7, 2011
Maximizing the power conversion efficiency of thin-film silicon solar cells
Design optimization could help maximize the power conversion efficiency of thin-film silicon solar cells
Silicon is readily available, easy to process, highly stable and non-toxic. It is also one of the best materials for making solar cells. The high quality and purity of silicon needed for fabricating the most efficient silicon-based solar cells, however, has made it difficult to lower production costs for this renewable energy technology. One approach that could reduce costs is to use a microscopically thin film of silicon with a textured surface to enhance light absorption. Navab Singh at the A*STAR Institute of Microelectronics and co-workers have now highlighted several key factors affecting the power conversion efficiency of surface-textured thin-film solar cells and come up with a ‘nanopillar’ design that maximizes light absorption and minimizes production costs.
Smallest electric motor
World's smallest electric motor made from a single molecule
Chemists at Tufts University's School of Arts and Sciences have developed the world's first single molecule electric motor, a development that may potentially create a new class of devices that could be used in applications ranging from medicine to engineering.
Monday, July 18, 2011
Flexible Solar Cells on Paper by MIT
Read more: MIT Unveils Flexible Solar Cells Printed on Paper | Inhabitat - Green Design Will Save the World.
Video: Dynamic folding of a paper solar cell circuit.
Tuesday, July 5, 2011
'Cling-film' solar cells could lead to advance in renewable energy
'Cling-film' solar cells could lead to advance in renewable energy
(PhysOrg.com) -- A scientific advance in renewable energy which promises a revolution in the ease and cost of using solar cells, has been announced today. A new study shows that even when using very simple and inexpensive manufacturing methods - where flexible layers of material are deposited over large areas like cling-film - efficient solar cell structures can be made.
Excerpt from the article:
"Dr Andrew Parnell of the University of Sheffield said, "Our results give important insights into how ultra-cheap solar energy panels for domestic and industrial use can be manufactured on a large scale. Rather than using complex and expensive fabrication methods to create a specific semiconductor nanostructure, high volume printing could be used to produce nanoscale (60 nanometers) films of solar cells that are over a thousand times thinner than the width of a human hair. These films could then be used to make cost-effective, light and easily transportable plastic solar cell devices such as solar panels."
"Over the next fifty years society is going to need to supply the growing energy demands of the world's population without using fossil fuels, and the only renewable energy source that can do this is the Sun", said Professor Richard Jones of the University of Sheffield. "In a couple of hours enough energy from sunlight falls on the Earth to satisfy the energy needs of the Earth for a whole year, but we need to be able to harness this on a much bigger scale than we can do now. Cheap and efficient polymer solar cells that can cover huge areas could help move us into a new age of renewable energy."
Solar cells
Photovoltaics are semiconductor devices that are used to generate low-cost renewable energy - most commonly as solar panels. When sunlight hits a photovoltaic cell, it is absorbed and its energy is converted into an electrical current. Most photovoltaic devices are made with silicon; however, devices can also be made from plastic (organic photovoltaic devices).
Plastic films can be deposited from solution by low-cost, roll to roll printing techniques resulting in significant overall savings in energy and cost. This is where the film is put on a roll and goes through a series of processes similar to the way newspapers are printed and taken off a roll at the end. There are currently products using this type of technology. To increase usage further, however, the technology needs to be more efficient. Polymer solar cells are currently 7-8% efficient.The next step is to develop cells which are 10% efficient or more for commercial viability.
The materials used in the research carried out by the collaboration are called PCDTBT (poly [N-9′-heptadecanyl-2,7-carbazole-alt-5,5-(4′,7′-di- 2-thienyl- 2′,1′,3′-benzothiadiazole): PCBM ([6,6]- phenyl-C61-butyric acid methylester), a material based on Nobel-prize-winning (Chemistry 1996) work of Professor Richard Smalley and Professor Harry Kroto (amongst others) on the C60 Buckminsterfullerene or buckyball form of carbon.Bright X-rays using instruments at Diamond Light Source were used to study the crystallinity of the material; neutrons at ISIS were used to examine the material's composition profile.
More information: The research is published in Advanced Energy Materials, volume 1, issue 4 July 2011.
Inkjet printing could change the face of solar energy industry
Inkjet printing could change the face of solar energy industry
Inkjet printers, a low-cost technology that in recent decades has revolutionized home and small office printing, may soon offer similar benefits for the future of solar energy.
From : http://www.physorg.com/news/2011-06-inkjet-solar-energy-industry.html
Engineers at Oregon State University have discovered a way for the first time to create successful "CIGS" solar devices with inkjet printing, in work that reduces raw material waste by 90 percent and will significantly lower the cost of producing solar energy cells with some very promising compounds.
High performing, rapidly produced, ultra-low cost, thin film solar electronics should be possible, scientists said.
The findings have been published in Solar Energy Materials and Solar Cells, a professional journal, and a patent applied for on the discovery. Further research is needed to increase the efficiency of the cell, but the work could lead to a whole new generation of solar energy technology, researchers say.
"This is very promising and could be an important new technology to add to the solar energy field," said Chih-hung Chang, an OSU professor in the School of Chemical, Biological and Environmental Engineering. "Until now no one had been able to create working CIGS solar devices with inkjet technology."
Part of the advantage of this approach, Chang said, is a dramatic reduction in wasted material. Instead of depositing chemical compounds on a substrate with a more expensive vapor phase deposition – wasting most of the material in the process – inkjet technology could be used to create precise patterning with very low waste.
"Some of the materials we want to work with for the most advanced solar cells, such as indium, are relatively expensive," Chang said. "If that's what you're using you can't really afford to waste it, and the inkjet approach almost eliminates the waste."
One of the most promising compounds and the focus of the current study is called chalcopyrite, or "CIGS" for the copper, indium, gallium and selenium elements of which it's composed. CIGS has extraordinary solar efficiency – a layer of chalcopyrite one or two microns thick has the ability to capture the energy from photons about as efficiently as a 50-micron-thick layer made with silicon.
In the new findings, researchers were able to create an ink that could print chalcopyrite onto substrates with an inkjet approach, with a power conversion efficiency of about 5 percent. The OSU researchers say that with continued research they should be able to achieve an efficiency of about 12 percent, which would make a commercially viable solar cell.
In related work, being done in collaboration with Greg Herman, an OSU associate professor of chemical engineering, the engineers are studying other compounds that might also be used with inkjet technology, and cost even less.
Some approaches to producing solar cells are time consuming, or require expensive vacuum systems or toxic chemicals. OSU experts are working to eliminate some of those roadblocks and create much less costly solar technology that is also more environmentally friendly. New jobs and industries in the Pacific Northwest could evolve from such initiatives, they say.
If costs can be reduced enough and other hurdles breached, it might even be possible to create solar cells that could be built directly into roofing materials, scientists say, opening a huge new potential for solar energy.
"In summary, a simple, fast, and direct-write, solution-based deposition process is developed for the fabrication of high quality CIGS solar cells," the researchers wrote in their conclusion. "Safe, cheap, and air-stable inks can be prepared easily by controlling the composition of low-cost metal salt precursors at a molecular level."
Thursday, June 23, 2011
Nanotechnology pushes battery life to eternity
(PhysOrg.com) -- A simple tap from your finger may be enough to charge your portable device thanks to a discovery made at RMIT University and Australian National University.
Sunday, May 29, 2011
Nanostructures improve solar cell efficiency
To make solar cells a competitive alternative to other renewable energy sources, researchers are investigating different alternatives. A step in the right direction is through new processes that change the surfaces of silicon solar cells. By creating different nanostructures on the surfaces, the energy harvesting properties of solar cells can be improved.
The Beginning..
Translation Say: "Call upon other (gods) whom ye fancy, besides Allah. They have no power,- not the weight of an atom,- in the heavens or on
earth: No (sort of) share have they therein, nor is any of them a helper to Allah.
(Katakanlah: " Serulah mereka yang kamu anggap (sebagai Tuhan) selain Allah, mereka tidak memiliki (kekuasaan) seberat zarrah pun di langit dan di bumi, dan mereka tidak mempunyai suatu saham pun dalam (penciptaan) langit dan bumi dan sekali-kali tidak ada di antara mereka yang menjadi pembantu bagi-Nya.) (Surah Saba’ 34: ayat 22)
Zarah or atom/particle is a basic unit of matter in which will built-up or combined with each other, in same or different species, to form bigger object or matter with more stable condition to it self or with surrounding. Nowadays, nanomaterials or nanotechnology has been among the emerging or maybe already esta
blished as one of the way in manipulating nature in order to get the most requisite properties of new materials of devices with a vast range of applications.
A nanometer is one-billionth of a meter, which is 10 by the power of minus 9 of a meter. With this size, a lot of properties of the materials give an interesting effect and sometime totally differ form its bulk properties. In electronic, medical and communication field, the idea of reducing the size of respective subject give a very important contribution to the mankind.
This blog will be contributing in collecting or
publishing the latest news or findings in nanotechnology/nanomaterials that are the area that the author is trying to embark right now. Any comment or information regarding to the subject matter in which the reader want to share with is highly appreciate.
Figure : Growth of ZnO near to the nanosize by hydrothermal method.