Graphene
The theory of graphene was first explored by Wallace in 1947 as a starting point for understanding the electronic properties of 3D graphite. The emergent massless Dirac equation was first pointed out by Semenoff, DiVincenzo and Mele. The earliest TEM images of few-layer graphite were published by Ruess and Vogt in 1948. An early, detailed study on few-layer graphite dates to 1962 when Boehm and colleagues reported producing monolayer flakes of reduced graphene oxide. Efforts to make thin films of graphite by mechanical exfoliation started in 1990, but nothing thinner than 50 to 100 layers was produced before 2004. Initial attempts to make atomically thin graphitic films employed exfoliation techniques similar to the drawing method. Multilayer samples down to 10 nm in thickness were obtained.
Graphene spray gun
A graphene spray gun is a kinetic spray system that deposits, through supersonic acceleration, a one atom thick sheet of pure carbon named graphene by means of a de Laval nozzle, a pinched tube with an hourglass type shape. The system deposits graphene flakes and a hexagonal graphene lattice is created upon impact of the desired surface. The graphene spray gun would be utilized onto large-scale applications such as circuits, radio transmitters, and optical electronics due to the grapehene’s transparency and its remarkable conductivity of electricity. The supersonic spray system was first developed in May 2014 by University of Illinois professor Alexander Yarin, and Korea University professor Sam Yoon. Yarin went to Yoon when he learned about his work regarding kinetic spray deposition systems. Yarin believed that graphene could be applied to the system in order to create a layer of the material. After conducting experiments with the newly created system, they concluded that the graphene spray system was a success. The spray gun is still in its early stages of development, but is considered by many scientists and researchers to be the solution of various predicaments that occur when applying graphene onto large-scale products. The most common problem that would transpire within the other methods is that the layer would be uneven and coated by aggregations. The energy delivered by the supersonic spraying stretches the graphene evenly upon impact, and is the main reason for the spray system’s lack of defects that are common within other graphene deposition methods.