Navigation Links
Breakthrough by U of T-led research team leads to record efficiency for next-generation solar cells
Date:7/29/2012

TORONTO, ON Researchers from the University of Toronto (U of T) and King Abdullah University of Science & Technology (KAUST) have made a breakthrough in the development of colloidal quantum dot (CQD) films, leading to the most efficient CQD solar cell ever. Their work is featured in a letter published in Nature Nanotechnology.

The researchers, led by U of T Engineering Professor Ted Sargent, created a solar cell out of inexpensive materials that was certified at a world-record 7.0% efficiency.

"Previously, quantum dot solar cells have been limited by the large internal surface areas of the nanoparticles in the film, which made extracting electricity difficult," said Dr. Susanna Thon, a lead co-author of the paper. "Our breakthrough was to use a combination of organic and inorganic chemistry to completely cover all of the exposed surfaces."

Quantum dots are semiconductors only a few nanometres in size and can be used to harvest electricity from the entire solar spectrum including both visible and invisible wavelengths. Unlike current slow and expensive semiconductor growth techniques, CQD films can be created quickly and at low cost, similar to paint or ink. This research paves the way for solar cells that can be fabricated on flexible substrates in the same way newspapers are rapidly printed in mass quantities.

The U of T cell represents a 37% increase in efficiency over the previous certified record. In order to improve efficiency, the researchers needed a way to both reduce the number of "traps" for electrons associated with poor surface quality while simultaneously ensuring their films were very dense to absorb as much light as possible. The solution was a so-called "hybrid passivation" scheme.

"By introducing small chlorine atoms immediately after synthesizing the dots, we're able to patch the previously unreachable nooks and crannies that lead to electron traps," explained doctoral student and lead co-author Alex Ip. "We follow that by using short organic linkers to bind quantum dots in the film closer together."

Work led by Professor Aram Amassian of KAUST showed that the organic ligand exchange was necessary to achieve the densest film.

"The KAUST group used state-of-the-art synchrotron methods with sub-nanometer resolution to discern the structure of the films and prove that the hybrid passivation method led to the densest films with the closest-packed nanoparticles," stated Professor Amassian.

The advance opens up many avenues for further research and improvement of device efficiencies, which could contribute to a bright future with reliable, low cost solar energy.

According to Professor Sargent, "Our world urgently needs innovative, cost-effective ways to convert the sun's abundant energy into usable electricity. This work shows that the abundant materials interfaces inside colloidal quantum dots can be mastered in a robust manner, proving that low cost and steadily-improving efficiencies can be combined."


'/>"/>

Contact: Liam Mitchell
liam.mitchell@utoronto.ca
416-978-4498
University of Toronto Faculty of Applied Science & Engineering
Source:Eurekalert

Related biology technology :

1. Innovation Leaders from Across Industries will Convene to Share Best Practices and Breakthrough Successes at Open Innovation Leadership Summit
2. Research breakthrough takes supercomputing out of the lab
3. Nanosurgery and the fight against cancer: Major breakthrough at Polytechnique Montral
4. Almost perfect: A breakthrough in superlens development
5. U of Toronto experiment named top breakthrough of 2011 by Physics World
6. Transparent material breakthrough
7. Microfabrication breakthrough could set piezoelectric material applications in motion
8. Tom Karagiannis, Ph.D. Awarded Future Fellowship by Australian Research Council (ARC)
9. Safeway Raises Over $9 Million to Fund Prostate Cancer Research
10. UK research paves way to a scalable device for quantum information processing
11. SRI International Researchers Developing Bioadhesive Gel to Protect Women from HIV and HSV Infections
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:10/12/2017)... ... 12, 2017 , ... AMRI, a global contract research, development ... patient outcomes and quality of life, will now be offering its impurity solutions ... new regulatory requirements for all new drug products, including the finalization of ICH ...
(Date:10/11/2017)... YORBA LINDA, CA (PRWEB) , ... October 11, ... ... adapted to upregulate any gene in its endogenous context, enabling overexpression experiments and ... activation (CRISPRa) system with small RNA guides is transformative for performing systematic gain-of-function ...
(Date:10/11/2017)... ... 2017 , ... Proscia Inc ., a data solutions ... “Pathology is going digital. Is your lab ready?” with Dr. Nicolas Cacciabeve, Managing ... how Proscia improves lab economics and realizes an increase in diagnostic confidence.* ...
(Date:10/11/2017)... ... October 11, 2017 , ... Disappearing forests and increased emissions ... over 5.5 million people each year. Especially those living in larger cities are affected ... based in one of the most pollution-affected countries globally - decided to take action. ...
Breaking Biology Technology:
(Date:4/24/2017)... -- Janice Kephart , former 9/11 Commission ... LLP (IdSP) , today issues the following statement: ... 6, 2017 Executive Order: Protecting the Nation ... instilled with greater confidence, enabling the reactivation of ... are suspended by until at least July 2017). ...
(Date:4/18/2017)... , April 18, 2017  Socionext Inc., a global expert ... a media edge server, the M820, which features the company,s hybrid ... software provided by Tera Probe, Inc., will be showcased during the ... the NAB show at the Las Vegas ... ...
(Date:4/13/2017)... , April 13, 2017 UBM,s Advanced ... will feature emerging and evolving technology through ... Innovation Summits will run alongside the expo portion of ... sessions, panels and demonstrations focused on trending topics within ... advanced design and manufacturing event will take place June ...
Breaking Biology News(10 mins):