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To enhance the practical utility of Vanadium dioxide (VO2) for thermochromic smart window applications, researchers have exerted numerous endeavors to improve its luminous transmittance (Tlum), and solar modulation ability (ΔTsol), lower the phase transition temperature (Tt), and narrow the thermal hysteresis curve (ΔT). In this study, thin hexagonal periodic perforated metal Vanadium films were prepared by magnetron sputtering using SiO2 microspheres as templates. Subsequently, the thin metal Vanadium film was subjected to rapid thermal annealing (RTA), developing a densely packed hexagonal network structure composed of VO2 nanoparticles. The formation of the nanoparticles was driven by increased surface mass transport during annealing and the imperative to reduce the system’s surface energy. Compared with the planar VO2 film, the two-dimensional nanostructure increases Tlum from 29.98 to 61.82%, decreases Tt from 55.91 to 44.44 °C, decreases ΔT from 15.18 to 4.98 °C, and slightly attenuates the ΔTsol from 5.92 to 3.84%. These enhancements are attributable to the reduced refractive index, the improved uniformity in particle size distribution, and the localized surface plasmon resonance (LSPR) effect. Moreover, the thermochromic properties were further augmented through a layer-by-layer stacking process. These findings underscore the potential for advancing the integration of VO2 particles in smart window technologies, thereby broadening their application prospects. [ABSTRACT FROM AUTHOR]

Vanadium dioxide (VO2), a current favorite in the field of smart windows as a thermochromic material, faces limitations in practical application due to its high phase transition temperature (Tt, ~ 68 ℃) and wide hysteresis curve (ΔT). In this study, Ru-doped VO2 thin films with reduced Tt and narrower ΔT were prepared through co-sputtering tetravalent metal Ru and V using magnetron sputtering to form alloy thin films, followed by rapid thermal annealing. Compared with pure VO2 thin films, at the Ru doping concentration of 4.98 at%, the Tt was lowered from 59.6 °C to 35.8 °C, and the ΔT was reduced from 10.5 °C to 2.8 °C, primarily due to the structural similarity between RuO2 and rutile phase VO2, smaller grain size, and greater grain uniformity. The optical properties of Ru-doped VO2 thin films had also been discussed, revealing only minor reductions in luminous transmittance (Tlum) and the solar modulation ability (ΔTsol) when the Tt decreased to 35.8 °C. This methodology offers a viable path for applying VO2 in smart windows, providing effective reductions in Tt and ΔT with minimal impact on optical performance. [ABSTRACT FROM AUTHOR]

As a promising thermochromic material for smart windows, VO2-based films have received extensive attention. To enhance the luminous transmittance (Tlum) of thermochromic smart windows without seriously affecting the solar modulation efficiency (ΔTsol), this paper prepared VO2 films by rapid thermal annealing of sputtered vanadium thin films on an ordered SiO2 nanosphere array, and then the ITO as antireflection layer was deposited on VO2 film by reactive magnetron sputtering. The surface morphology, crystal structure and optical transmittance of the films were characterized by Scanning Electron Microscopy, X-ray diffraction and UV–VIS–NIR spectrophotometer, respectively. The SiO2 nanospheres provide continuous refractive index gradient, while the deposition of the ITO antireflection layer creates conditions for thin film interference, thereby synergistically reducing surface reflection in the VO2-based smart window. Compared with the planar VO2 thin film (Tlum, 39.1%), the ITO/VO2/SiO2 composite structure can significantly increase the Tlum from 39.1 to 55.5%, an increase of nearly 16.4%, while the ΔTsol is basically unchanged. The results provide an effective strategy for improving the performance of smart windows. [ABSTRACT FROM AUTHOR]

Zinc stannate (Zn2SnO4) films were deposited on MgO (100) substrates by pulsed laser deposition, and Zn2SnO4 monocrystalline films were obtained by postannealing process. The structures, surface morphologies, and optical properties of the Zn2SnO4 films annealed at different temperatures were investigated in detail. Crystal structure analyses showed that the film annealed at 800°C was single crystal Zn2SnO4 with an inverse‐spinel structure. The heteroepitaxial mechanism was further clarified by a schematic diagram, and the epitaxial relationships between the film and substrate were Zn2SnO4 (400)||MgO (200) with Zn2SnO4 [001]||MgO [001]. The obtained Zn2SnO4 films exhibited excellent transparency. The optical band gap of the 800°C‐annealed Zn2SnO4 film was about 3.97 eV. The extinction coefficients and refractive indexes of the Zn2SnO4 films annealed at different temperatures as a function of wavelength were analyzed in detail. [ABSTRACT FROM AUTHOR]

Kiwifruit is moderately sweet and sour and quite popular among consumers; it has been widely planted in some areas of the world. In 2019, the crown gall disease of kiwifruit was discovered in the main kiwifruit-producing area of Guizhou Province, China. This disease can weaken and eventually cause the death of the tree. The phylogeny, morphological and biological characteristics of the bacteria were described, and were related to diseases. The pathogenicity of this species follows the Koch hypothesis, confirming that A. fabacearum is the pathogen of crown gall disease of kiwifruit in China. In this study, Loop-mediated isothermal amplification (LAMP) analysis for genome-specific gene sequences was developed for the specific detection of A. fabacearum. The detection limit of the LAMP method is 5 × 10−7 ng/μL, which has high sensitivity. At the same time, the amplified product is stained with SYBR Green I after the reaction is completed, so that the amplification can be detected with the naked eye. LAMP analysis detected the presence of A. fabacearum in the roots and soil samples of the infected kiwifruit plant. The proposed LAMP detection technology in this study offers the advantages of ease of operation, visibility of results, rapidity, accuracy and high sensitivity, making it suitable for the early diagnosis of crown gall disease of kiwifruit. [ABSTRACT FROM AUTHOR]

Rutile SnO2 epitaxial films are deposited on MgF2 (001) substrates at different substrate temperatures (540–660 °C) by metal organic chemical vapor deposition. Structural, optical, and electrical properties of the films as well as the epitaxial mechanism are investigated in detail. The structure analyses manifest that the film deposited at 620 °C is rutile phase SnO2 and exhibits the best crystallinity. The epitaxial relationships are determined as SnO2 (110) || MgF2 (001) with SnO2 [001] || MgF2 [110] and [1¯10]. The Hall mobility, resistivity, and carrier concentration of the 620 °C‐deposited film are 10.4 cm2 · V−1 · s−1, 0.75 Ω · cm, and 8.1 × 1017 cm−3 respectively. The average transmittance in the visible range of the SnO2 film deposited at 620 °C exceeds 88% and the optical band gap is about 3.93 eV. High‐quality epitaxial rutile SnO2 films are successfully deposited on single crystalline MgF2 (001) substrate for the first time by metal organic chemical vapor deposition. The average transmittance of all SnO2 films in the visible range exceeds 86%. The structural, electrical, and optical properties are investigated in detail. The samples show temperature‐dependent structural and electrical properties. The epitaxial mechanism is also proposed. [ABSTRACT FROM AUTHOR]