Researchers developing 2-D materials similar to graphene

February 2, 2018, Science and Technology of Advanced Materials
This visualisation shows layers of graphene used for membranes. Credit: University of Manchester

Chemists are working to synthesize the next generation of super materials for high-performance electronics, solar cells, photodetectors and quantum computers. While they have made progress with compound materials, they have not yet succeeded in developing unaltered or "freestanding" materials for such devices, according to a review published in the journal Science and Technology of Advanced Materials.

Graphene is a carbon material derived from graphite, the same type of material found in pencils, but it is arranged in a one-atom-thin honeycomb lattice. Discovered in 2004, graphene's two-dimensional arrangement gives it "extraordinary" properties, including extreme strength and "marvelously high" electron conductivity.

However, the tight lattice lacks a semiconducting bandgap, which is essential for electronic devices. Therefore, scientists have been hunting for alternative materials that have bandgaps, but still have a graphene-like structure.

Much focus has been placed on graphene quantum dots, which are small segments of graphene, about 10 to 100 nm carbon hexagons across and less than 30 atomic sheets thick. To make the dots behave more like 2-D graphene, research teams have added other molecules to change the structure and function of the material.

For example, one team attached molecular groups containing nitrogen to graphene quantum dots. They found that different molecular combinations altered the electronic structure of the quantum dot in unique ways. This shifted the color of light the material produced when exposed to electricity, which is useful for and photodetectors. Several teams have built and tested photodetectors using with success. The material has also been shown to improve the performance of dye-sensitized .

Researchers are also investigating silicon and germanium analogs of graphene, called silicene and germanene, and their respective hydrogenated forms, silicane and germanane. They are testing how different preparation methods and structures, such as multiple layers and added molecules, affect performance for potential electronic or photonic devices.

While silicene and germanene have not been prepared without added molecules so far, the modified materials strongly resemble the 2-D materials theoretically predicted. Understanding the properties of the modified materials is a "good starting point" for developing future nanomaterials, according to the paper authors.

Ultimately, the reviewers, led by Hideyuki Nakano of Toyota Central R&D Labs in Japan, are optimistic that and energy storage materials could be developed using these in the near future.

Explore further: Resonant energy transfer from quantum dots to graphene

More information: Hideyuki Nakano et al. Chemical modification of group IV graphene analogs, Science and Technology of Advanced Materials (2018). DOI: 10.1080/14686996.2017.1422224

Related Stories

Resonant energy transfer from quantum dots to graphene

May 22, 2014

Semiconductor quantum dots (QDs) are nanoscale semiconductors that exhibit size dependent physical properties. For example, the color (wavelength) of light that they absorb changes dramatically as the diameter decreases. ...

New insights on graphene

December 21, 2017

Graphene floating on water does not repel water, as many researchers believe, but rather attracts it. This has been demonstrated by chemists Liubov Belyaeva and Pauline van Deursen and their supervisor Grégory F. Schneider. ...

Scientists move graphene closer to transistor applications

August 29, 2017

Scientists at the U.S. Department of Energy's Ames Laboratory were able to successfully manipulate the electronic structure of graphene, which may enable the fabrication of graphene transistors— faster and more reliable ...

New method of characterizing graphene

May 30, 2017

Scientists have developed a new method of characterizing graphene's properties without applying disruptive electrical contacts, allowing them to investigate both the resistance and quantum capacitance of graphene and other ...

Researchers uncover new light harvesting potentials

July 14, 2016

Researchers for the first time have found a quantum-confined bandgap narrowing mechanism where UV absorption of the graphene quantum dots and TiO2 nanoparticles can easily be extended into the visible light range.

Recommended for you

Weaponizing oxygen to kill infections and disease

August 19, 2018

The life-threatening bacteria called MRSA can cripple a hospital since it spreads quickly and is resistant to treatment. But scientists report that they are now making advances in a new technique that avoids antibiotics. ...

Flexible color displays with microfluidics

August 16, 2018

A new study published on Microsystems and Nanoengineering by Kazuhiro Kobayashi and Hiroaki Onoe details the development of a flexible and reflective multicolor display system that does not require continued energy supply ...

Twisted electronics open the door to tunable 2-D materials

August 16, 2018

Two-dimensional (2-D) materials such as graphene have unique electronic, magnetic, optical, and mechanical properties that promise to drive innovation in areas from electronics to energy to materials to medicine. Columbia ...

Scientists discover why silver clusters emit light

August 16, 2018

Clusters of silver atoms captured in zeolites, a porous material with small channels and voids, have remarkable light-emitting properties. They can be used for more efficient lighting applications as a substitute for LED ...

Novel sensors could enable smarter textiles

August 16, 2018

A team of engineers at the University of Delaware is developing next-generation smart textiles by creating flexible carbon nanotube composite coatings on a wide range of fibers, including cotton, nylon and wool. Their discovery ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.