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Vanadium dioxide (VO2) thin films with pure Monoclinic phase could be transformed from B-phase by inserting TiO2 buffer layers on transparent amorphous glass substrates at the low temperature of 400 °C. This crystalline transformation might be ascribed to oxygen-deficient environment induced by the TiO2 buffer layer and the template effect of TiO2 layer for M-VO2 phase. The simplicity in phase regulation of the present method and the superior optical and electrical properties of the films may allow its wide applications in thermo-opto-electro sensing devices. Keywords: Vanadium dioxide, TiO2 buffer layers, Photoelectric properties

Zr50Cu50, Zr47Cu44Al9, Zr46.3Cu43.4Al8.3Nb2 and Zr41.2Ti13.8Cu17.5Ni5Be22.5 thin film metallic glasses (TFMGs) were prepared by pulsed laser deposition (PLD) on glass substrates at room temperature. The effect of thickness on the electrical and optical properties of the Zr-based TFMGs was investigated. It was found that the resistivity of the Zr-based TFMGs basically decreased as the thickness varied from 10 nm to 40 nm. Interestingly, while the transmittance in the visible region decreased significantly with the increase of thickness, the transmittance in the near-infrared range still remained at a high level of larger than 80%. Through the characterization of electrical properties, the high transmittance of the Zr-based TFMGs in the near-infrared range was attributed to their rather low carrier concentration. Our findings provided the possibility for TFMGs to be used as transparent electrodes in the field of near infrared sensors and solar cells. Keywords: Thin film metallic glass, Zr-based alloys, Transmittance, Near infrared

We reported here the studies of a series of Zr20Ti20Hf20M20Be20 (M = Cu, Ni and Co) quinary high entropy bulk metallic glasses. Glasses with critical diameters (Dc) of 3 mm, 8 mm and 5 mm, respectively has been successfully fabricated by copper mold casting. Strikingly, a plastic strain of 11.6% is achieved in the Zr20Ti20Hf20Cu20Be20 metallic glass. The dynamic fragility the Zr20Ti20Hf20Cu20Be20 alloy is determined from calorimetric measurements. The excellent plasticity is explained to be attributed to relatively higher fragility. Keywords: High entropy alloys, Bulk metallic glasses, Glass forming ability, Mechanical property and fragility

Novel AZO/Zr50Cu50/AZO tri-layer transparent conductive films with excellent transmittance in both visible and near infrared region were successfully prepared by pulsed laser deposition on glass substrates. The electrical and optical properties were investigated at various Zr50Cu50 thicknesses. As the AZO thickness was fixed at 50 nm and Zr50Cu50 thickness was varied between 1 and 18 nm, it was found that AZO (50 nm)/Zr50Cu50/AZO (50 nm) tri-layer films exhibited good conductivity and high transmittance in both visible and near infrared wavelength. Additionally, both the electrical and optical properties of AZO (50 nm)/Zr50Cu50 (2 nm)/AZO (50 nm) tri-layer films were found to be sensitive to the growth temperature. In this work, the lowest sheet resistance (43 Ω/□) and relatively high transmittance (∼80%) in the range of 400–2000 nm were achieved while the growth temperature was 350 °C. Furthermore, the AZO (50 nm)/Zr50Cu50 (2 nm)/AZO (50 nm) thin film deposited at 350 °C exhibits the highest figure of merit of 1.42 × 10−3 Ω−1, indicating that the multilayer is promising for coated glasses and thin film solar cells. Keywords: Transparent conductive oxide, AZO, Zr50Cu50, Electrical and optical properties, Visible and near infrared transmittance

A series of Zr35−xTi30Cu7.5Be27.5Fex (x = 0–10) bulk metallic glasses are cast using water-cooled copper mold casting technique. The glass forming ability (GFA) and thermal stability of Zr35−xTi30Cu7.5Be27.5Fex alloys were studied by means of X-ray diffraction and differential scanning calorimetry. It was found that the Zr35−xTi30Cu7.5Be27.5Fex (x = 2, 3, 5 and 7, respectively) alloys could be cast into glassy cylindrical rods with a diameters up to 20 mm. However, higher Fe content (x = 10) deteriorates the GFA remarkably. The supercooled liquid region (ΔTx), γ parameter (defined as Tx/(Tg + Tl)) and the reduced glass transition temperature Trg (defined as Tg/Tl) are employed to evaluate the GFA in Zr35−xTi30Cu7.5Be27.5Fex (x = 0–10) alloys. The results showed that Trg was more effective in gauging the GFA of the Zr35−xTi30Cu7.5Be27.5Fex alloy systems than ΔTx and γ parameter. In addition, elastic constant (Poisson’s ratio) was also employed as a gauge to evaluate the glass forming ability in Zr35−xTi30Cu7.5Be27.5Fex alloys. Keywords: Zr-based alloys, Bulk metallic glasses, Glass forming ability, Thermal stability and elastic properties

Mn-doped 3C-SiC film has been prepared onto the Si (111) substrate by employing a molecular beam epitaxy method. The experimental analysis establishes that the prepared sample shows the ferromagnetic property with a relatively high Curie temperature (Tc) of 355 K, which is an exciting phenomenon on account of the scarceness in the SiC-based diluted magnetic semiconductor. The analysis derived from the X-ray diffraction and absorption spectroscopy patterns indicates that Mn atoms should react with Si atoms and then form Mn4Si7 compounds. Combined with the theoretical simulation, it is speculated that a new alloy phase of Mn4Si7Cx maybe appear, which should be responsible for the exceptionally high Tc ferromagnetic behavior in the sample.

Vanadium dioxide (VO2) with reversible metal–insulator transition (MIT) is one of the most promising energy-efficient materials. Especially for VO2-based smart windows, the visible transmittance and solar modulation ability are the most critical parameters. However, VO2 thin films that are directly deposited onto glass substrates are of poor crystallinity and MIT performance, limiting the practical applications of VO2/glass heterostructures. In this paper, a buffer layer of Cu50Zr50 was introduced to build a novel Zr-based thin film metallic glass (VO2/Cu50Zr50/glass) with multilayer structures for thermochromic applications. It is observed that the insertion of a Cu50Zr50 buffer layer with appropriate thickness results in a clear enhancement of crystalline quality and MIT performance in the VO2/Cu50Zr50/glass thin films, compared with the single-layer VO2/glass thin films. Moreover, the VO2/Cu50Zr50/glass bi-layer films exhibit better optical performance with enhanced solar modulation ability (ΔTsol = 14.3%) and a high visible transmittance (Tvis = 52.3%), which represents a good balance between ΔTsol and Tvis for smart window applications.