Preparation Of TiO₂ Multilayer Anti-Reflection Coatings With Self-cleaning By Sol-gel Method

Solar cells have become a recognized backup energy source to help resolve the energy crisis.In use,they often face the problem of contamination by the surface of the battery.Plating a layer of self-cleaning film on the surface of solar cells can effectively prevent the damage to the battery from pollutants.This article focuses on improving the self-cleaning performance of TiO₂ materials,and combines the principle of antireflection,focusing on providing an easy-to-operate,low-energy-consumption,highefficiency anti-reflection film with self-cleaning performance.Firstly,using butyl titanate,glacial acetic acid,distilled water,ethanol,etc.as raw materials,nano-TiO₂ hydrosols were prepared through hydrolysis,mixing,polymerization,water bath and other steps,and then spin-coated coating,preheating,and annealing steps were used to obtain TiO₂ thin films.The orthogonal test method was used to design the experimental scheme,and the effects of various factors on the photocatalytic activity of TiO₂ sol were studied,and the best scheme was obtained by summing up.The results show that the ion doping concentration added to the TiO₂ sol has the largest effect on the photocatalytic degradation activity,followed by the light time,p H value,and the environmental temperature of the photocatalytic degradation have the smallest effect.The best solution is 8% Ag+ doping,2h light,p H value in the rangle of 2⁴,and the ambient temperature of photocatalytic degradation is 20 ℃.Secondly,combining the self-cleaning performance of TiO₂ with the antireflection film in combination with the principle of antireflection,the common low refractive index material Mg F2-Si O2 is selected,and the optical simulation software TFCalc is used to simulate the physical thickness and refractive index of the thin film to ensure self-cleaning Under the premise of performance,the physical thickness and refractive index parameters of the film system with better antireflection effect are obtained.After experimental testing and analysis,the physical parameters of the film system were optimized.Finally,a TiO₂-Si O2 mixed film was selected to control the physical thickness of the film.The film with good anti-reflection effect and good self-cleaning effect was obtained.Thirdly,the prepared sol was characterized by X-ray diffraction,ultravioletvisible spectrophotometer,scanning electron microscopy,X-ray photoelectron spectroscopy and other testing methods to characterize and analyze the thin film deposited on the glass substrate by spin coating.The results show that the prepared TiO₂ sol is anatase-type grains,the film morphology is uniform and complete,no pores and cracks,and good optical properties.The photocatalytic degradation experiment of aqueous methylene blue solution shows that the film has good photocatalytic performance.Finally,the TiO₂ film with good photocatalytic performance was successfully prepared,and the maximum photodegradation degree of the methylene blue hydrosol at a concentration of 10 mg/L reached 98%.The TiO₂-Si O2 mixed film has selfcleaning and anti-reflection performance,and the average reflectance in the 380 800 nm band range reaches 8% and the photodegradation rate reaches 41%.