High Efficiency Anti-Reflectance Graphene-based Coating through Electrochemical Etching and Deposition

Antireflection (AR) coating is of great significance in controlling the reflection index (RI), which influences optical performance of the system. Comparing to the traditional absorbing materials, single layer graphene with much lower mass density, absorbs 2.3% of light at visible frequencies, which makes it an ideal candidate for use in mass-sensitive systems. The electrochemical anisotropic etching and electrophoretic deposition of graphene can minimize the RI of Aluminum material to 1%, meanwhile the mechanical properties of the coating is acceptable. Electrochemical anisotropic etching (EAE) with prior cathodic polarization during anodic etching, forms homogeneous digital AR structure on the centimeter-scale Aluminum material surface, with pit number density and size distribution controllable and improved interfacial binding force. Electrophoretic deposition (EPD) forms graphene-oxide-based nanostructures on the three-dimensional Aluminum surface from Graphene oxide aqueous suspension. The graphene-based AR coating is achieved through the catalytic reduction of graphene oxide by visible light with N-doped TiO2 as photocatalyst. By electrochemical treatment, we manufacture the high efficiency absorbtion ability and low RI optical surface of Aluminum material, through conducting digital AR structure and homogeneous AR coating.