Preparation Of Antireflection Coatings Based On Solid/Hollow Silica Nanospheres And Its Application Research On Graphene Transparent Conductive Films

Antireflection coatings?ARCs?are widely applied in solar cells,optical devices,display screens and other devices to reduce the reduction on the substrate surface.Two types of structure usually be designed,single layer ARCs and gradient refractive index?GRIN?ARCs.Single layer ARCs can reach high transmittance at a certain wavelength of incidence light,however,it is mainly obtained by directly stacking and depositing nanoparticles,preparing porous structure and depositing dispersive nanoparticles at present.The structures obtained by these ways are needs to be optimized.GRIN ARCs can achieve broadband antireflection properties,which can be mainly formed via two ways:?i?multilayer structure;?ii?moth-eye-like array structure.Multilayer structure can achieve broadband antireflection performance,but it was constructed by series of layers with a strict matching relationship for refractive index of each layer.Moth-eye-like array structures have been usually fabricated by complicated etching.Therefore,designing a single layer ARCs with good optical performance and controllable structure and obtaining moth-eye-like ARCs by a simple and inexpensive method have become hot spots in the current ARCs research.The ARCs can be applied to graphene transparent conductive films because it can increase the transmittance of substrate.In this paper,single layer close-packed antireflection structure and moth-eye-like antireflection structure have been prepared using hollow SiO₂ nanospheres to regulate the refractive index of ARCs,and by sol-gel method.The close-packed antireflection structure has been applied to prepare a graphene/antireflection structure composite transparent conductive film with good photoelectric properties.The research contents of this paper are as follows.?1?The close-packed solid/hollow silica nanospheres?c-S/HSNSs?array were prepared by sol-gel method using solid silica nanospheres?SSNSs?and hollow silica nanospheres?HSNSs?.The average transmittance of the antireflection array in the visible regioncan reach 97.21%,and the maximum transmittance can reach 98.50%.This method can fabricate the antireflection structure with compact array and high optical performance,which embodies the advantages of both performance and structure.?2?SSNSs and HSNSs silica nanospheres moth-eye-like array structure were constructed using solid/hollow composite SiO₂ nanospheres.The moth-eye-like array structure had high transmittance in visible band and little dependence on the incident light angle,with an average solar transmittance of 97.75%in the visible region.The moth-eye-like array structure prepared by this method avoids complex etching technology,and shows the advantages of low cost and simple preparation process.?3?The c-S/HSNSs array were assembled on quartz substrates,then depositing graphene films using catalysis of copper foil in ambient pressure chemical vapor deposition to obtain graphene/antireflection structure composite transparent conductive films,which effectively improved the optical and electrical performances of graphene transparent conductive film.The sheet resistance of composite transparent conductive film is 0.688-0.879 k?·sq^-1,and the transmittance increased from 80.56%to 84.69%.It is an effective way to improve the properties of graphene transparent conductive films via assembling antireflection structures between graphene and substrate.