Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Better lighting, power with quantum dots, nanomaterials

Ghassan Jabbour
Ghassan Jabbour

Abstract:
Imagine flexible lighting devices manufactured by using printing techniques. Imagine solar power sources equally as reliable and as portable as any conventional power source.

Such advances are among aims of research at Arizona State University to find ways of more effectively harnessing solar power and producing more energy-efficient, durable and custom-designed light sources. The work is now drawing support from two international corporations.

Better lighting, power with quantum dots, nanomaterials

Tempe, AZ | Posted on March 15th, 2009

U.S.-based Solterra Renewable Technologies Inc. and Nitto Denko Corp. of Japan are investing more than $3.7 million through grants to help fund the research led by ASU engineering professor Ghassan Jabbour.

Jabbour's work focuses on the use of nanomaterials and quantum dots in solar cells and solid state lighting. Technical advances in this area "will open the way for a new wave of more efficient and portable power and light sources in as many shapes and varieties as designers can imagine," he says.

Jabbour, who teaches in ASU's School of Materials, is doing his research through the Advanced Photovoltaics Center, which he directs. The center is part of the Arizona Institute for Renewable Energy at ASU. Jabbour also is director of optoelectronics research for the Flexible Display Center, part of the univerisity's Ira A. Fulton School of Engineering.

Illuminating printing processes

Work funded by the grants will include the study of the materials science, physics and engineering solutions necessary to produce the next generation of solar cells, which will cost less to produce and perform more efficiently, Jabbour says.

The project is an example of the economic benefit a research university can bring to its state. Each year, Arizona universities contribute nearly $1 billion into the Arizona economy from their research, most of which is funded by the U.S. government and entities from outside the state. Research money brought in by universities is restricted money that can be used only for the research activity it supports. It cannot be used to compensate for cuts in other parts of the university's budget.

The quantum dots/solar cells project already has brought a small company to open new operations at the ASU Research Park. Given the increasing interest in solar energy and the means to produce it at lower costs, the company can be expected to grow rapidly, Jabbour says.

One of the major scientific and engineering challenges of Ghassan's project involves how to employ printing techniques to fabricate low-cost alternatives to current solar cells. Research articles on printed organic solar cells written by Jabbour and other members of his team continue to be cited by fellow researchers more than any other articles in the area of printed ultra-thin solar area research. (Ultra-thin means it involves materials less than 100 times the thickness of a typical human hair.)

Printing is a viable method for mass production of solar cells. Some printing techniques, such as silk-screen printing (commonly used to print logos, numbers and pictures on textiles), are already used in some aspects of solar cell manufacturing.

Printing allows for large numbers of solar-cell devices to be manufactured rapidly, thus eventually bringing down costs.

"In our work, we will be investigating various techniques such as inkjet printing, screen printing, and roll-to-roll, which is similar to newspaper printing techniques, to see what works best for solar cell manufacturing," Jabbour says.

The power of photons

The material science and engineering aspect of the projects involves experiments with materials that exhibit unique properties at the nanoscale, specifically materials that use photons to achieve more efficient conversion of energy into electricity. The materials also have a broader absorption spectrum of incident solar light - meaning they can make more effective use of solar light for conversion into electricity.

"It's traditional to generate one electron-hole pair for every absorbed photon in most solar cells," Jabbour says, but researchers in his lab are working on generating more multiple electron-hole pairs per photon to achieve increased power-conversion efficiency. This is accomplished by producing a higher number of electrons for each absorbed photon from incident light.

In most bulk semiconducting materials, Jabbour explains, absorption of an incident photon (light quanta) with the right energy can excite an electron enough to move it across an energy band gap - thus resulting in an electron-hole pair. But the same photon might generate more than one electron-hole pair if the material is made into much smaller dimensions - such as the size of a quantum dot.

Quantum dots are small particles about few nanometers (a billionth of a meter) in size. By adjusting the particles' physical dimensions, their optical and electronic properties can be fine-tuned. Through such a process, the resulting characteristics of the materials are different than the characteristics of the same material in bulk size, Jabbour explains.

The challenge is how to extract most of the charges from the dots to transfer in the form of electrical current to the device being powered by the solar cell, he says.

Recent results of 3 percent in power conversion in this area are encouraging. Such an efficiency will continue to climb as better materials and device structures are being developed, which is a part of Jabbour's work supported by the grants.

Energy conservation goals

More efficient solar cells are only one part of the solution to the nation's growing energy needs. Just as important is making efficient use of energy in conventional systems, Jabbour says.

The two technologies he and his team are working on are interrelated, involving both energy generation and energy conservation. Although there is a strong push for alternative energy, including solar energy, Jabbour says much can be accomplished by focusing on research to lower the power consumption of conventional technologies. This work involves the area of solid state lighting.

One of the corporate grants is supporting work directly aimed at understanding the materials and device physics of nanoscale structures for low-power, nanothick solid state lighting applications.

The materials used are hybrid nanomaterials targeting white-light emission from a single building block. The light source made out of these materials also will have a nano-range thickness and can be operated at high brightness (equivalent to a ceiling lamp) using a 9-volt battery source. Just as with solar cells, these light sources will also be printable in the future, Jabbour says.

Flexibility in lighting devices

"The beauty of these two projects is their compatibility with rugged substrates, including flexible ones," he says.

A substrate is a material on which circuits or other small devices are formed or fabricated. Flexible substrates (for example, plastic, thin metal foils, or cloth) allow for more durable lights that also weigh less than conventional lighting devices and can be produced in a variety of shapes.

"Imagine a light that is made on a roll that can be cut into various shapes according to the desire of the user," Jabbour says. Such an advance is still far off, but not impossible. In fact, he points out, printed lights made out of inorganic phosphors that operate at about 120 to 150 volts are already available. The drawback is that currently they can be operated only at such high voltages.

The two technologies promise to provide low-cost, high-efficiency solar cells and solid state lights that can be made on thin flexible substrates, resulting in light-weight durable modules that are easier to place on roof tops (for example, solar-cell arrays) and indoors (lamps and similar lighting devices).

####

For more information, please click here

Contacts:

Joe Kullman

(480) 965-8122
Ira A. Fulton School of Engineering

Copyright © Arizona State University

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Superconductivity: Footballs with no resistance - Indications of light-induced lossless electricity transmission in fullerenes contribute to the search for superconducting materials for practical applications February 9th, 2016

SUNY Poly and GLOBALFOUNDRIES Announce New $500M R&D Program in Albany To Accelerate Next Generation Chip Technology: Arrival of Second Cutting Edge EUV Lithography Tool Launches New Patterning Center That Will Generate Over 100 New High Tech Jobs at SUNY Poly February 9th, 2016

Making sense of metallic glass February 9th, 2016

Electron's 1-D metallic surface state observed: A step for the prediction of electronic properties of extremely-fine metal nanowires in next-generation semiconductors February 9th, 2016

Display technology/LEDs/SS Lighting/OLEDs

Graphene is strong, but is it tough? Berkeley Lab scientists find that polycrystalline graphene is not very resistant to fracture February 7th, 2016

Organic crystals allow creating flexible electronic devices: The researchers from the Faculty of Physics of the Moscow State University have grown organic crystals that allow creating flexible electronic devices February 5th, 2016

Researchers discover new phase of boron nitride and a new way to create pure c-BN February 5th, 2016

PEN Inc. Announces Strategy to Broaden Clarity Branded Products Business February 4th, 2016

Discoveries

Making sense of metallic glass February 9th, 2016

Electron's 1-D metallic surface state observed: A step for the prediction of electronic properties of extremely-fine metal nanowires in next-generation semiconductors February 9th, 2016

Nanoparticle therapy that uses LDL and fish oil kills liver cancer cells February 9th, 2016

Leading bugs to the death chamber: A kinder face of cholesterol February 8th, 2016

Announcements

Superconductivity: Footballs with no resistance - Indications of light-induced lossless electricity transmission in fullerenes contribute to the search for superconducting materials for practical applications February 9th, 2016

SUNY Poly and GLOBALFOUNDRIES Announce New $500M R&D Program in Albany To Accelerate Next Generation Chip Technology: Arrival of Second Cutting Edge EUV Lithography Tool Launches New Patterning Center That Will Generate Over 100 New High Tech Jobs at SUNY Poly February 9th, 2016

Making sense of metallic glass February 9th, 2016

Electron's 1-D metallic surface state observed: A step for the prediction of electronic properties of extremely-fine metal nanowires in next-generation semiconductors February 9th, 2016

Energy

Canadian physicists discover new properties of superconductivity February 8th, 2016

Host-guest nanowires for efficient water splitting and solar energy storage February 7th, 2016

February 4th, 2016

Putting silicon 'sawdust' in a graphene cage boosts battery performance: Approach could remove major obstacles to increasing the capacity of lithium-ion batteries January 30th, 2016

Quantum Dots/Rods

Nanoscale cavity strongly links quantum particles: Single photons can quickly modify individual electrons embedded in a semiconductor chip and vice versa February 8th, 2016

The iron stepping stones to better wearable tech without semiconductors February 8th, 2016

QD Vision Named to the 2015 Global Cleantech 100 Under the Radar List: Quantum Dot Leader Recognized for Clean Technology Innovation January 26th, 2016

Light-activated nanoparticles prove effective against antibiotic-resistant 'superbugs' January 19th, 2016

Solar/Photovoltaic

Host-guest nanowires for efficient water splitting and solar energy storage February 7th, 2016

Simplifying solar cells with a new mix of materials: Berkeley Lab-led research team creates a high-efficiency device in 7 steps January 29th, 2016

An alternative to platinum: Iron-nitrogen compounds as catalysts in graphene January 28th, 2016

Scientists provide new guideline for synthesis of fullerene electron acceptors January 28th, 2016

Printing/Lithography/Inkjet/Inks

Teijin to Participate in Nano Tech 2016 January 21st, 2016

New bimetallic alloy nanoparticles for printed electronic circuits: Production of oxidation-resistant copper alloy nanoparticles by electrical explosion of wire for printed electronics January 5th, 2016

Photonic “sintering” may create new solar, electronics manufacturing technologies December 1st, 2015

Screen Printable Functionalised Graphene Ink November 3rd, 2015

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic