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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]

(Zr47Cu44Al9)100−xSix (x = 0, 0.5, 1.5 and 2.5 at%) thin-film metallic glasses (TFMGs) were deposited at glass substrate by pulsed laser deposition. The influence of Si content and substrate temperature on the microstructure, optical and electrical properties was investigated. After adding Si in the Zr47Cu44Al9 system, the transmittance of the films enhances obviously, especially in the near-infrared region. The resistivity increases and becomes more sensitive to the temperature due to Si addition. With increasing substrate temperatures from room temperature to 430 °C, (Zr47Cu44Al9)98.5Si1.5 films display fully amorphous structure. Appropriate substrate temperature drastically decreases the resistivity of films without degrading the transmittance. (Zr47Cu44Al9)98.5Si1.5 TFMG deposited at 330 °C exhibits the visible transmittance of 49.38%, the infrared transmittance of 80.27% and the resistivity of 7.62 mΩ cm, which are useful properties for their potential applications in infrared technology with the high requirement of radiation resistance and corrosion resistance. [ABSTRACT FROM AUTHOR]

The Cs-Pb-Br system possesses excellent optical properties and unique phase transition characteristics due to soft lattice structures. Herein, a simple and green synthetic method based on self-assembly in Dimethyl formamide (DMF) is proposed to prepare CsPb 2 Br 5 nanocrystals (NCs) with typical tetragonal structure, which exhibit orange emission and small size around 3.87 nm. Interestingly, the phase transition from CsPb 2 Br 5 to CsPbBr 3 occurs easily in DMF through mechanical induction, while the metastable mixed-phase structural CsPbBr 3 NCs with an average size of about 5 nm appear and show bright yellow emission. Afterwards, in combination with the supersaturation crystallization method, stable cubic CsPbBr 3 NCs with 13 nm size are obtained and display the effective green emission. The synthesized CsPb 2 Br 5 and steady-state CsPbBr 3 NCs exhibit good optical stability in solution, while the metastable CsPbBr 3 NCs undergo a change in emission from yellow to green with increasing time. [Display omitted] • Orange luminescent tetragonal CsPb 2 Br 5 nanocrystals with small size of 3.87 nm are synthesized by green self-assembly method. • Metastable CsPbBr 3 nanocrystals with size of 5.12 nm were prepared by mechanically induced phase transition from CsPb 2 Br 5. • Metastable CsPbBr 3 nanocrystals exhibit bright yellow emission and undergo a change to green with increasing time. [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]

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]