Study On Synthesis And Properties Of Coated Glass Of SiO₂ Aerogel-VO₂ Film With Energy Saving Function

Building energy consμmption occupies a large proportion in total energy consμmption and through the doors and Windows energy loss is the main part, so energy saving glass is development trend in future. This article researches intelligent energy saving coated glass based on different wavelengths of sunlight and energy transmission. Obtained the following results:VO2 thin film was prepared by polymer deposition with good thermochromism performance by sol-gel technology. We find the preparation condition of VO2 thin film with better structure and properties by means of heat treatment conditions (atmosphere heat treatment, heat treatment temperature, heat treatment time), namely vacuμm atmosphere and 530 ℃ can get better thermochromic film; Integral transmittance of the visible region reached 42%, the amplitude of variation of transmittance in the region of the near infrared light was 50%; Explored the thickness of film which constrainly influence two factors:transmittance of visible light and amplitude of variation of transmittance in the region of the near infrared light. For 40nm thick film, transmittance of visible light can reach 72%, but its near-infrared light transmittance regulation amplitude is only 10%. When the film thickness is more than 200 nm, transmittance of visible light significantly decreased to 15%, the infrared region of the light transmittance regulating range is 16%; Studied the unusual +4 valence metal Zr doping, along with the increase of the doping amount phase transition down to 50 ℃, but the resistance mutations is reduced to 1.08. Performance of thermochromism is reduced too, the near-infrared light transmittance regulation amplitude is only 20%.With MTMS as silicon source precursor, ambient pressure and sol-gel method by changing the parameters such as methanol content, dry heat treatment temperature, control of chemical additives, to explore suitable preparation conditions, in order to get into a good membranous, high porosity, good thermal conductivity and low heat insulation performance of SiO2 aerogel films. In methanol content is 0.30 Mol-0.53 Mol, with the increase of the solvent, aerogel films by cracking severity has significantly reduced; When the heat treatment temperature raised to 550 ℃, porosity is 89%, the thermal conductivity of membrane layer theoretical value decreased to 0.019 W/mK; When the secondary dispersion solvent quantity is 15 ml, adding glycerol ratio 1.7 ×10-3 mol, sample thickness was 1.7 μm, thermal conductivity of aerogel film coated glass is reduced than the glass substrate, the overall thermal conductivity of the coated glass down to 1.28 W/(mK).Such composite coated glass was prepared with heat insulation and thermochromic properties. The aerogel layer is plated on the surface of VO2 film to prevent oxidation and antireflection of visible light. Integral transmittance of the visible region reached 45%, the amplitude of variation of transmittance in the region of the near infrared light was 46%...