Diamond used to produce graphene quantum dots and nano-ribbons of controlled structure

May 17, 2012

Kansas State University researchers have come closer to solving an old challenge of producing graphene quantum dots of controlled shape and size at large densities, which could revolutionize electronics and optoelectronics.

Vikas Berry, William H. Honstead professor of chemical engineering, has developed a novel process that uses a diamond knife to cleave graphite into graphite nanoblocks, which are precursors for graphene quantum dots. These nanoblocks are then exfoliated to produce ultrasmall sheets of of controlled shape and size.

By controlling the size and shape, the researchers can control graphene's properties over a wide range for varied applications, such as , electronics, optical dyes, biomarkers, composites and particulate systems. Their work has been published in Nature Communications and supports the university's vision to become a top 50 public research university by 2025. The article is available online.

"The process produces large quantities of graphene quantum dots of controlled shape and size and we have conducted studies on their structural and ," Berry said.

While other researchers have been able to make quantum dots, Berry's research team can make quantum dots with a controlled structure in large quantities, which may allow these optically active quantum dots to be used in solar cell and other optoelectronic applications.

"There will be a wide range of applications of these quantum dots," Berry said. "We expect that the field of graphene quantum dots will evolve as a result of this work since this new material has a great potential in several nanotechnologies."

It has been know that because of the and , the shape and size of graphene dictate their electrical, optical, magnetic and chemical properties. This work also shows proof of the opening of a band-gap in graphene nanoribbon films with a reduction in width. Further, Berry's team shows through high-resolution transmission electron micrographs and simulations that the edges of the produces structures are straight and relatively smooth.

Explore further: In-situ nanoindentation study of phase transformation in magnetic shape memory alloys

Related Stories

Graphene quantum dots: The next big small thing

Jan 12, 2012

A Rice University laboratory has found a way to turn common carbon fiber into graphene quantum dots, tiny specks of matter with properties expected to prove useful in electronic, optical and biomedical applications.

Coupling of Single Quantum Dots to Smooth Metal Films

Jul 20, 2009

Scientists at Argonne National Laboratory's CNM Nanophotonics Group have measured how light emission from individual colloidal semiconductor nanocrystals, or quantum dots, is modified when in proximity to ...

Recommended for you

'Exotic' material is like a switch when super thin

Apr 18, 2014

(Phys.org) —Ever-shrinking electronic devices could get down to atomic dimensions with the help of transition metal oxides, a class of materials that seems to have it all: superconductivity, magnetoresistance ...

User comments : 0

More news stories

NASA's space station Robonaut finally getting legs

Robonaut, the first out-of-this-world humanoid, is finally getting its space legs. For three years, Robonaut has had to manage from the waist up. This new pair of legs means the experimental robot—now stuck ...

Ex-Apple chief plans mobile phone for India

Former Apple chief executive John Sculley, whose marketing skills helped bring the personal computer to desktops worldwide, says he plans to launch a mobile phone in India to exploit its still largely untapped ...

Filipino tests negative for Middle East virus

A Filipino nurse who tested positive for the Middle East virus has been found free of infection in a subsequent examination after he returned home, Philippine health officials said Saturday.

Egypt archaeologists find ancient writer's tomb

Egypt's minister of antiquities says a team of Spanish archaeologists has discovered two tombs in the southern part of the country, one of them belonging to a writer and containing a trove of artifacts including reed pens ...