According to the report of the Physicist Organization Network on April 11 (Beijing time), scientists at the Massachusetts Institute of Technology and Harvard University have used DNA to construct graphene nanostructures with unique electronic properties, and to produce large-scale production of graphene electronic chips. A very important step has been taken. The research results were published in the recent "Nature and Communications" magazine.
By controlling the DNA sequence and manipulating molecules to form DNA nanostructures of different folded shapes, the scientists can use this as a template to control the nanostructure of inorganic materials, thereby forming different nanoscale patterns on a carbon atom-rich graphene sheet.
These DNA nanostructures were developed in the laboratory using a method called single stranded DNA. This artificially synthesized DNA single-stranded piece is a bit like a children's toy. Each single-stranded piece can be combined with four specific structures and interlocked with each other to form a DNA nanostructure of a specified shape. Currently, researchers have used this DNA single-stranded chip to construct more than 100 complex nanoscale patterns.
Because DNA will degrade under exposure to sunlight and oxygen and react with other molecules, it is not an ideal material. The researchers transferred the encoded DNA structure information to more stable graphene. First, the researchers used aminopyrine to immobilize the DNA on the surface of graphene, then applied silver to the surface of the DNA, and deposited gold on the silver. After the surface of the molecule is covered with gold, a stable metallized DNA can be formed. By using a plasma etching technique, uncovered graphene can be removed to form a graphene structure having the same original shape as the DNA, and finally be reused. Remove metallized DNA.
The team used this technique to create a wide variety of shapes, including rings and ribbons. They found that although most of the structural information did not change, some structural information was lost during the metallization of DNA, so this technique is not as accurate as electron beam lithography. However, the use of electron beam lithography to build graphene nanostructures is costly, time consuming, and difficult to scale up.
The structure of particular interest to scientists is the graphene ribbon. It is very narrow and can limit the electrons of the material. Graphene usually does not have a bandgap, which is a characteristic of typical transistors. Graphene ribbons, however, have bandgap and can therefore be used as electronic circuit components. Scientists are also very interested in graphene rings because they can be used as quantum interference transistors.
In the long run, this DNA nanostructure processing method will help researchers design and build graphene electronic circuits. Building graphene electronic circuits has always been a scientist's dream, but how to place nanowires or nanotubes on these tiny carbon structures onto graphene sheets has always been an unsolved difficulty. The use of metallized DNA to process graphene structures makes this process very easy. According to Robert Harden, a professor of chemistry and environmental engineering at the University of California, the concept of this new method is very novel, demonstrating the potential of metallized DNA for the preparation of graphene electronic circuits and will certainly promote the research and development of graphene nanoelectronic devices. (Reporter He Wei)
Garden Ornaments,Iron Garden Ornaments,Cast Iron Components
Aluminum window Co., Ltd. , http://www.iron-fence-manufacturer.com