Nav: Home

ORNL demonstrates large-scale technique to produce quantum dots

May 19, 2016

OAK RIDGE, Tenn., May 19, 2016 - A method to produce significant amounts of semiconducting nanoparticles for light-emitting displays, sensors, solar panels and biomedical applications has gained momentum with a demonstration by researchers at the Department of Energy's Oak Ridge National Laboratory.

While zinc sulfide nanoparticles - a type of quantum dot that is a semiconductor - have many potential applications, high cost and limited availability have been obstacles to their widespread use. That could change, however, because of a scalable ORNL technique outlined in a paper published in Applied Microbiology and Biotechnology.

Unlike conventional inorganic approaches that use expensive precursors, toxic chemicals, high temperatures and high pressures, a team led by ORNL's Ji-Won Moon used bacteria fed by inexpensive sugar at a temperature of 150 degrees Fahrenheit in 25- and 250-gallon reactors. Ultimately, the team produced about three-fourths of a pound of zinc sulfide nanoparticles - without process optimization, leaving room for even higher yields.

The ORNL biomanufacturing technique is based on a platform technology that can also produce nanometer-size semiconducting materials as well as magnetic, photovoltaic, catalytic and phosphor materials. Unlike most biological synthesis technologies that occur inside the cell, ORNL's biomanufactured quantum dot synthesis occurs outside of the cells. As a result, the nanomaterials are produced as loose particles that are easy to separate through simple washing and centrifuging.

The results are encouraging, according to Moon, who also noted that the ORNL approach reduces production costs by approximately 90 percent compared to other methods.

"Since biomanufacturing can control the quantum dot diameter, it is possible to produce a wide range of specifically tuned semiconducting nanomaterials, making them attractive for a variety of applications that include electronics, displays, solar cells, computer memory, energy storage, printed electronics and bio-imaging," Moon said.

Successful biomanufacturing of light-emitting or semiconducting nanoparticles requires the ability to control material synthesis at the nanometer scale with sufficiently high reliability, reproducibility and yield to be cost effective. With the ORNL approach, Moon said that goal has been achieved.

Researchers envision their quantum dots being used initially in buffer layers of photovoltaic cells and other thin film-based devices that can benefit from their electro-optical properties as light-emitting materials.

Co-authors of the paper, titled "Manufacturing demonstration of microbially mediated zinc sulfide nanoparticles in pilot-plant scale reactors," were ORNL's Tommy Phelps, Curtis Fitzgerald Jr., Randall Lind, James Elkins, Gyoung Gug Jang, Pooran Joshi, Michelle Kidder, Beth Armstrong, Thomas Watkins, Ilia Ivanov and David Graham. Funding for this research was provided by DOE's Advanced Manufacturing Office and Office of Science. The paper is available at

UT-Battelle manages ORNL for the DOE's Office of Science. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit
Quantum dots:

Caption: A method to produce significant amounts of semiconducting nanoparticles for light-emitting displays, sensors, solar panels and biomedical applications has gained momentum with a demonstration by researchers at Oak Ridge National Laboratory.


Cutline: Using this 250-gallon reactor, ORNL researchers produced three-fourths of a pound of zinc sulfide quantum dots, shown in the inset.

NOTE TO EDITORS: You may read other press releases from Oak Ridge National Laboratory or learn more about the lab at Additional information about ORNL is available at the sites below:

Twitter -

RSS Feeds -

Flickr -

YouTube -

LinkedIn -

Facebook -

DOE/Oak Ridge National Laboratory

Related Quantum Dots Articles:

Graphene and quantum dots put in motion a CMOS-integrated camera that can see the invisible
ICFO develops the first graphene-based camera, capable of imaging visible and infrared light at the same time.
Platelets instead of quantum dots
A team of researchers led by ETH Zurich professor David Norris has developed a model to clarify the general mechanism of nanoplatelet formation.
Quantum dots illuminate transport within the cell
Biophysicists from Utrecht University have developed a strategy for using light-emitting nanocrystals as a marker in living cells.
'Flying saucer' quantum dots hold secret to brighter, better lasers
By carefully controlling the size of the quantum dots, the researchers can 'tune' the frequency, or color, of the emitted light to any desired value.
'Flying saucer' colloidal quantum dots produce brighter, better lasers
A multi-institutional team of researchers from Canada and the US has demonstrated steady state lasing with solution-processed nanoparticles called 'colloidal quantum dots,' an important step on the path to improving laser tools for fiber optics, video projectors and more accurate medical testing technology.
Quantum dots with impermeable shell: A powerful tool for nanoengineering
Depending on their applications, quantum dots need to be tailored in terms of their structure and properties.
USC quantum computing researchers reduce quantum information processing errors
USC Viterbi School of Engineering scientists found a new method to reduce the heating errors that have hindered quantum computing.
A new form of hybrid photodetectors with quantum dots and graphene
ICFO researchers develop a hybrid photodetector comprising an active colloidal quantum dot photodiode integrated with a graphene phototransistor.
ORNL demonstrates large-scale technique to produce quantum dots
ORNL demonstrates a method to produce significant amounts of semiconducting nanoparticles for light-emitting displays, sensors, solar panels and biomedical applications.
First single-enzyme method to produce quantum dots revealed
Three Lehigh University engineers have successfully demonstrated the first precisely controlled, biological way to manufacture quantum dots using a single-enzyme, paving the way for a significantly quicker, cheaper and greener production method.

Related Quantum Dots Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Changing The World
What does it take to change the world for the better? This hour, TED speakers explore ideas on activism—what motivates it, why it matters, and how each of us can make a difference. Guests include civil rights activist Ruby Sales, labor leader and civil rights activist Dolores Huerta, author Jeremy Heimans, "craftivist" Sarah Corbett, and designer and futurist Angela Oguntala.
Now Playing: Science for the People

#521 The Curious Life of Krill
Krill may be one of the most abundant forms of life on our planet... but it turns out we don't know that much about them. For a create that underpins a massive ocean ecosystem and lives in our oceans in massive numbers, they're surprisingly difficult to study. We sit down and shine some light on these underappreciated crustaceans with Stephen Nicol, Adjunct Professor at the University of Tasmania, Scientific Advisor to the Association of Responsible Krill Harvesting Companies, and author of the book "The Curious Life of Krill: A Conservation Story from the Bottom of the World".