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Hafnium oxide (HfO2) multilayer films were prepared on a glass substrate by pulsed laser deposition, and a novel middle metal layer of Cu40Ag60 was developed. The influence of CuAg thickness and substrate temperature on structural, optical, electrical and morphological characteristics of HfO2/CuAg/HfO2 films were carefully investigated. Multilayer films with different CuAg thickness deposited at room temperature exhibit amorphous structures. As the CuAg thickness varies from 4 to 24 nm, the visible transmittance is kept between 63 and 80%, while the near-infrared transmittance and sheet resistance undergo significant reduction. Increasing the substrate temperature from 100 ℃ to 350 ℃ induces the transformation of HfO2 from amorphous to the crystalline structure, while the near-infrared transmittance and sheet resistance gradually increase. HfO2(50 nm)/CuAg(16 nm)/HfO2(50 nm) multilayer film grown at 150 ℃ exhibits optimal optical and electrical properties with the transmittance of 78.2% in the visible region, 17.7% in the near-infrared region, sheet resistance of 8.59 Ω/◻ and the highest figure of merit of 1.09 × 10–2 Ω−1, which are useful for their potential application in the field of heat mirror and optoelectronics. Furthermore, the possible mechanisms involved in obtaining low infrared transmittance and reduced sheet resistance were explored. [ABSTRACT FROM AUTHOR]

High-performance vanadium dioxide (VO 2) thin films with high luminous transmittance and solar modulation ability were successfully fabricated on Zr x O y /glass substrate by pulsed laser deposition. By controlling the growth temperature of the buffer layer, the stoichiometry and crystal structure of Zr x O y buffer layer can be converted from cubic Zr 2 O phase to monoclinic ZrO 2 phase. Through such a transformation, the luminous transmittance (T lum), solar modulation ability (Δ T sol), the transition temperature and the width of thermal hysteresis loop have been tuned without diminishing the thermochromic property. It is found that the insertion of ZrO 2 layer results in a remarkable enhancement of the luminous transmittance and the solar modulation ability when compared to single-layer VO 2 film. The findings in the present work may provide some new strategies for the commercialization of VO 2 films in the field of smart energy-efficient windows. • The ZrO2 film with monoclinic crystal structure was used as the buffer layer in the preparation of high-quality VO2 films by Pulsed Laser Deposition. • The glass/ZrO2/VO2 composite films with impressive photoelectric properties were obtained. [ABSTRACT FROM AUTHOR]

• SnO 2 /VO 2 /SnO 2 thermochromic films are prepared by pulsed laser deposition. • Balance between luminous transmittance and solar modulation ability is achieved. • All the SnO 2 /VO 2 /SnO 2 tri-layer films show good hydrophobicity. The SnO 2 /VO 2 /SnO 2 (SVS) multilayer films were prepared using pulsed laser deposition and were characterized by X-ray diffraction, Raman spectroscopy, scanning electron microscopy, Hall Effect Measurement System, double beam spectrophotometer and contact angle measurements. The results showed that SVS multilayer films with excellent thermochromic properties were obtained by adjusting the preparation temperature of the SnO 2 buffer layer and antireflection layer. When the preparation temperature of the SnO 2 layer was 320 °C, the phase transition amplitude (ΔR) of the VO 2 film reached 354 times and both the phase transition temperature (T c) and hysteresis loop width (ΔH) could be effectively reduced. Meanwhile, the SVS multilayer film had satisfactory luminous transmittance (50.2%) and solar modulation ability (15.3%), achieving the balance of optical properties. In addition, all the SVS multilayer films exhibited excellent hydrophobicity. Boiling water experiments show that the service life of SVS tri-layer film is twice that of SV bi-layer film. This work suggests that the SVS multilayer films are a good candidate for VO 2 -based smart windows. [ABSTRACT FROM AUTHOR]

• High quality SnO 2 /VO 2 bi-layer films are prepared by pulsed laser deposition. • The grain size and roughness of VO 2 can be regulated by SnO 2 buffer layer. • Balance between luminous transmittance and solar modulation ability is achieved. For decades, the practical application of VO 2 -based smart windows is limited by its low luminous transmittance (T lum) and solar modulation ability (ΔT sol). In this study, SnO 2 /VO 2 thermochromic thin films were produced on amorphous glass substrates via pulsed laser deposition and were characterized by x-ray diffraction, scanning electron microscopy, atomic force microscopy, spectrophotometry, and resistance measurements. By adjusting the thickness of SnO 2 buffer layer, not only the semiconductor-to-metal transition temperature of VO 2 films can be effectively tuned, but also the T lum and ΔT sol of VO 2 films can be increased synchronously to 54.9% and 8.3%, respectively. It is shown that the grain size of VO 2 films increases from ~15 nm to ~90 nm with the SnO 2 buffer layer thicknesses increase from 25 nm to 125 nm, and consequently the electrical and optical properties of VO 2 films are effectively improved. These can be attributed to the fact that SnO 2 buffer layer can effectively control the grain size, surface roughness and optical band gap of VO 2.The results suggest that the SnO 2 buffer layer is very beneficial for the growth of high-quality VO 2 films on glass substrates, which is of importance for the application of VO 2 in energy-efficient smart windows. [ABSTRACT FROM AUTHOR]

In this study, high-quality thermochromic vanadium dioxide (VO 2) thin films were grown on ZrO 2 /glass by pulsed laser deposition and were investigated using X-ray diffraction (XRD), atomic force microscopy (AFM), double beam spectrophotometry and Hall Effect measurement system. Based on XRD results, it can be inferred that the crystal structure of ZrO 2 buffer layer can be transformed between monoclinic and tetragonal structures with the increase of buffer layer thickness. Photoelectric performance tests showed that the introduction of ZrO 2 buffer layer considerably reduced the phase transition temperature (T c) and hysteresis loop width (Δ H) of the VO 2 films and allowed the visible light transmittance (T lum) and solar modulation ability (Δ T sol) of the films to be tuned effectively. Especially, when the thickness of the ZrO 2 buffer layer was 50 nm, the T c of the VO 2 films reached the minimum value of 48 °C. When the ZrO 2 buffer layer thickness increased to 125 nm, the sheet resistance change of the VO 2 film attained two orders of magnitude, and their T lum-90°C and Δ T sol were as high as 50.01% and 7.88%, respectively. These results showed that the ZrO 2 buffer layer considerably affected the growth of VO 2 films on amorphous glass substrates and was beneficial for the application of VO 2 in energy-saving smart windows. [ABSTRACT FROM AUTHOR]