New method for producing graphene quantum dots with controlled shape and size

According to a report by the physicist organization network on May 18 (Beijing time), researchers at Kansas State University have developed a new method to produce a large number of graphene quantum dots with controlled shape and size, which will be electronic Revolutionary changes in the fields of science, optoelectronics and electromagnetism. The relevant research report was published in the recently published Journal of Nature Communication. Due to edge states and quantum limitations, the shape and size of graphene nanostructures (GN) will determine their electrical, optical, magnetic, and chemical properties. At present, top-down GN synthesis methods include lithography, ultrasonic chemistry, fullerene entrainment, and carbon nanotube release. However, these methods have problems such as low productivity, uncontrollable shape and size, unsmooth edges, inability to easily transfer to other substrates, or dissolution in other solvents. Professors Vickers Berry and other researchers in the Department of Chemical Engineering of the school used the diamond blade to nano-cut graphite to become graphite nano-blocks, which is the premise of forming graphene quantum dots. These nanoblocks will then flaky off to form ultra-small carbon atoms, resulting in a graphene structure with an ID/IG ratio between 0.22 and 0.28 and a roughness below 1 nm. The research team demonstrated through high-resolution transmission electron microscopy and simulation that the resulting GN edges are straight and smooth, and by controlling the shape of the GN (square, rectangle, triangle, and ribbon) and size (up to 100 nanometers), the researchers can Widely control the properties of graphene for solar cells, electronic devices, optical dyes, biomarkers and composite particle systems. Berry said that the new graphene quantum dot materials have great potential in the field of nanotechnology, and they hope to further promote the development of graphene quantum dots through this research. Graphene has appeared in just a few years, and many people in the industry have predicted that it will become the backbone of the future electronics industry. The manufacture of nanoscale graphene dots to replace silicon crystal cells is a key step in the application of graphene in the electronics industry, and is also the goal of scientists in various countries. At the beginning of this year, Rice University of the United States successfully used carbon fiber to make nano-scale graphene wafers, which is much more efficient than before. This time, the successful "graphite nano-cutting" method of the University of Kansas, which can control the shape of graphene nano-dots, undoubtedly opened up a new technical idea.

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