کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1664102 1518008 2016 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Study of low temperature rf-sputtered Mg-doped vanadium dioxide thermochromic films deposited on low-emissivity substrates
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد فناوری نانو (نانو تکنولوژی)
پیش نمایش صفحه اول مقاله
Study of low temperature rf-sputtered Mg-doped vanadium dioxide thermochromic films deposited on low-emissivity substrates
چکیده انگلیسی


• Thermochromic VO2 was deposited by sputtering at low substrate temperature and low deposition rate.
• The thermochromic properties of VO2 were studied by doping with Mg.
• Temperature dependence transmittance revealed optimum Mg doping.
• Mg doping increased luminous transmittance and reduced critical temperature.
• Excess Mg destroyed thermochromic properties.

Undoped VO2 was fabricated by RF sputtering from metallic target on low emissivity glass substrates at a record low growth temperature. The structure of the films was examined by X-Ray Diffraction whereas temperature dependence transmittance was employed for monitoring the film's thermochromic properties. Thermochromic VO2 could be achieved at the substrate temperature of 300 °C which is the lowest growth temperature of VO2 phase by sputtering reported in literature without any additional post-deposition annealing treatment of the films. The thermochromic properties obtained for undoped VO2 were: luminous transmittance of 36.2%, metal-to-insulator transition temperature at 55.7 °C and infrared transmittance modulation, ΔTIR, (transmittance difference in the infrared, at λ = 2000 nm, when heated from 25 °C to 90 °C) by 20.5% and solar transmittance modulation ΔTsol = 5.2%. Subsequently, magnesium (Mg) was introduced in the structure of thermochromic VO2 up to 2.4 at.%, and the Mg-induced changes in thermochromisity were examined. By increasing the amount of Mg in VO2 structure the visible transmittance increased up to 70%. Improvement in thermochromic characteristics was observed for atomic percentage of Mg up to 0.3% above which the films tend to be non-thermochromic. The optimum atomic percentage of Mg (0.3 at.%) leads to thermochromic VO2 with the characteristic lowest phase transition temperature at 49.2 °C, luminous transmittance ΤIum = 46.6% and solar transmittance modulation ΔΤsol = 2.8% and ΔΤIR = 13%. Overall, 70 nm thick thermochromic VO2 films deposited at the low substrate temperature of 300 °C and low deposition rate 0.75 nm/min when doped with Mg up to 0.3 at.% resulted in vanadium dioxide with improved thermochromic properties is regarded as particularly promising for smart windows applications on flexible substrates.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Thin Solid Films - Volume 601, 29 February 2016, Pages 99–105
نویسندگان
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