Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

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

GrapheneCanada 2016 International Conference: Recent advances in technology developments and business opportunities in graphene commercialization August 31st, 2016

FEI Celebrates Shipment of 1,000th Helios DualBeam System: FEIís Helios Family has lead the DualBeam technology race and is widely used across the semiconductor, materials science, life sciences and oil & gas industries August 31st, 2016

Colors from darkness: Researchers develop alternative approach to quantum computing August 31st, 2016

Diamonds and quantum information processing on the nano scale August 31st, 2016

Display technology/LEDs/SS Lighting/OLEDs

Continuous roll-process technology for transferring and packaging flexible LSI August 29th, 2016

McMaster researchers resolve a problem that has been holding back a technological revolution August 18th, 2016

Leading Advanced Materials Manufacturer Pixelligent Closes $10.4 Million in Funding: Capital Will Boost Capacity for North American Manufacturing, Drive Asian Expansion, and Continue Innovation in Solid State Lighting and OLED Display Applications August 16th, 2016

Towards a better screen; New molecules promise cheaper, more efficient OLED displays August 9th, 2016

Discoveries

FEI Celebrates Shipment of 1,000th Helios DualBeam System: FEIís Helios Family has lead the DualBeam technology race and is widely used across the semiconductor, materials science, life sciences and oil & gas industries August 31st, 2016

Colors from darkness: Researchers develop alternative approach to quantum computing August 31st, 2016

Diamonds and quantum information processing on the nano scale August 31st, 2016

Device to control 'color' of electrons in graphene provides path to future electronics August 31st, 2016

Announcements

GrapheneCanada 2016 International Conference: Recent advances in technology developments and business opportunities in graphene commercialization August 31st, 2016

FEI Celebrates Shipment of 1,000th Helios DualBeam System: FEIís Helios Family has lead the DualBeam technology race and is widely used across the semiconductor, materials science, life sciences and oil & gas industries August 31st, 2016

Colors from darkness: Researchers develop alternative approach to quantum computing August 31st, 2016

Diamonds and quantum information processing on the nano scale August 31st, 2016

Energy

New electrical energy storage material shows its power: Nanomaterial combines attributes of both batteries and supercapacitors August 25th, 2016

Lehigh engineer discovers a high-speed nano-avalanche: New findings published in the Journal of Electrochemical Society about the process involving transformations in glass that occur under intense electrical and thermal conditions could lead the way to more energy-efficient glas August 24th, 2016

New flexible material can make any window 'smart' August 23rd, 2016

Researchers reduce expensive noble metals for fuel cell reactions August 22nd, 2016

Quantum Dots/Rods

Quantum dots with impermeable shell: A powerful tool for nanoengineering August 12th, 2016

Diamond-based light sources will lay a foundation for quantum communications of the future: Electrified quantum diamond can become the heart of quantum networks and computers of the future August 7th, 2016

A new type of quantum bits July 29th, 2016

Researchers develop faster, precise silica coating process for quantum dot nanorods July 12th, 2016

Solar/Photovoltaic

Let's roll: Material for polymer solar cells may lend itself to large-area processing: 'Sweet spot' for mass-producing polymer solar cells may be far larger than dictated by the conventional wisdom August 12th, 2016

NREL technique leads to improved perovskite solar cells August 11th, 2016

Making a solar energy conversion breakthrough with help from a ferroelectrics pioneer: Philadelphia-based team shows how a ferroelectric insulator can surpass shockley-queisser limit August 9th, 2016

Tiny high-performance solar cells turn power generation sideways August 5th, 2016

Printing/Lithography/Inkjet/Inks

Tailored probes for atomic force microscopes: 3-D laser lithography enhances microscope for studying nanostructures in biology and engineering/ publication in Applied Physics Letters August 11th, 2016

Smarter self-assembly opens new pathways for nanotechnology: Brookhaven Lab scientists discover a way to create billionth-of-a-meter structures that snap together in complex patterns with unprecedented efficiency August 9th, 2016

Nanoscientists develop the 'ultimate discovery tool': Rapid discovery power is similar to what gene chips offer biology June 25th, 2016

Perovskite solar cells surpass 20 percent efficiency: EPFL researchers are pushing the limits of perovskite solar cell performance by exploring the best way to grow these crystals June 13th, 2016

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