Note: Crystal nanoparticles are produced and propagated using various methods, such as CVD, laser irradiation, and discharge . CVD method is the best option for the industrial production of crystal nanoparticles. The reason for this is the low cost-to-income ratio as well as the possibility of vertical growth of crystal particles on the desired substrate . In this process, the crystal nanoparticles in the negative electrode are sublimated, which is due to the high temperature in the discharge process. Since this method was used for the synthesis of crystal nanoparticles for the first time, it is known as the most common method of producing crystal nanoparticles . In this method, there are both types of crystal nanoparticles , single-walled and multi-walled, with lengths up to 50 microns containing structural defects. In the process of laser radiation, a laser is used to vaporize graphite and an inert gas is used to direct these vapors into the tank. Crystal nanoparticles grow on the cold surface of the reactor . It is suitable for the production of multi-walled crystal nanoparticles . And by using graphite composite and metal catalyst particles of cobalt and nickel combination (for the synthesis of crystal nanoparticles) . The efficiency of this process is 70 % and its main product is crystal nanoparticles , the diameter of these crystal nanoparticles is completely controllable and the diameter of the crystal nanoparticles can be controlled as desired by changing the temperature. He used the CVD method with the help of a catalyst to produce crystal nanoparticles . During the CVD process, a layer of nickel, cobalt and metal catalyst particles, generally iron, is used to produce crystal nanoparticles . CVD is a common method for the commercial production of crystal nanoparticles . In this method, the diameter of crystal nanoparticles is related to the dimensions of metal particles. By patterning the substrate, using heat treatment and H plasma etching of the catalyst, the diameter of the crystal nanoparticles can be controlled.