In nano coatings, the application of nano silicon plays a vital role. First, the hardness of nano silicon is close to that of diamond, so adding it to the coating can greatly improve the hardness and wear resistance of the coating and extend the service life of the coating. Secondly, the nano silicon particles are extremely small and have no obvious light absorption and scattering in the visible light band, so adding it to the coating can maintain the high transparency of the coating itself, which is especially important for optical coatings. In addition, nano silicon has a large specific surface area and a large bonding area with the base material, which can significantly improve the adhesion between the coating and the base.