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In this paper, FTO conductive glass was used as a substrate to successfully prepare Co3 O4 thin films with controlled morphology by hydrothermal method. Using the prepared Co3 O4 thin films as the base, Co3 O4 @ BiVO4 composite thin films with varying amounts of BiVO4 were successfully prepared by controlling the number of spin-coating cycles. The phase composition and microstructure were analyzed using X-ray diffraction (XRD) and field-emission scanning electron microscopy (FESEM). Additionally, their optical absorption and photoelectric properties were measured using a UV-3600 UV-Vis spectrophotometer and an electrochemical workstation. Results indicate that, based on the XRD patterns of the Co3 O4 @ BiVO4 composite thin films, the composite materials were successfully prepared. From the FESEM images, it can be observed that the prepared Co3 O4 @ BiVO4 composite thin films possess a continuous, uniform, and dense surface, with the Co3 O4 thin films growing uniformly as nanowires, and the spin-coated BiVO4 uniformly coating the surfaces of Co3 O4 nanowires in a block-like manner. The optical absorption spectrum reveals enhanced light absorption of the Co3 O4 @ BiVO4 composite thin films compared to pure Co3 O4 thin films. Under zero bias voltage and illumination, the photoelectrical performance of the Co3 O4 @ BiVO4 composite thin films surpasses that of pure Co3 O4 thin films. Electrochemical test results demonstrate that the Co3 O4 @ BiVO4 -3 composite thin films, which were spun-coated three times, showing optimal photoelectrical performance, with a maximum photocurrent approximately 18.4 times that of pure Co3 O4 thin films. The responsivity of the device is 105. 5 μA/W, with a detectivity of up to 1. 988 ×1011 Jones. [ABSTRACT FROM AUTHOR]

With the rapid advancement of optical communication technology and integrated electronic devices, magneto-optical thin films, particularly rare earth iron garnet (RIG), have emerged as the most promising materials for near-infrared communication windows in recent years. In order to minimize the impact on the related properties of magneto-optical thin films during the preparation process, it's important to select the substrate materials. Silicon and garnet oxides are commonly used as substrates for the preparation of RIG magneto-optical thin films. The lattice constant of RIG magneto-optical thin films is generally around 12. 4 Å, and gallium-containing garnet oxide single crystal substrates have a similar lattice constant, which shows large lattice constant characteristics, making them one of the suitable substrate materials. However, the raw material gallium oxide is volatile at high temperature, the preparation of gallium-containing garnet single crystal has been a hot topic. The further study of gallium garnet series substrate single crystals is expected to promote the development of a new magnetooptical devices. In this paper, we reviewed the research of gallium garnet series single crystal, summarized the work of our team in the growth, structure and key parameters of these crystals, and outlooked the trend of research and development. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Liquid Crystal & Displays is the property of Chinese Journal of Liquid Crystal & Displays and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study utilized density functional theory (DFT) in quantum chemistry to investigate the gas-phase parasitic reaction mechanism between diethylzinc (DEZn) and tert-butanol (t-BuOH) during the metal-organic chemical vapor deposition (MOCVD) growth process of ZnO thin films. By calculating the Gibbs free energy changes along various reaction pathways at different temperatures, a comprehensive thermodynamic evaluation of key intermediates (HOZnOBut, H(ZnO)2 But, HZnOH), as well as the formation of dimers (Zn2 O2 H4, Zn2 O4 H4, Zn4 O4 H4), and trimers (Zn3 O6 H6) was performed. The main objective was to identify potential pathways and products that could lead to the formation of nanoparticles, which might impede ZnO thin film growth. Research has shown that under high-temperature deposition conditions (673.15 K

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract:In this paper, porous n-GaN thin films with a pore density of 1. 51 x 1010 Cm-2 and an average pore size of 38 nm were initially prepared by UV-assisted electrochemical etching (UV-EC). Subsequently, a series of ZnxCu1- xS composite films, with x values of 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0, were deposited on the porous n-GaN films by water bath method. The bandgaps of the porous n-GaN/ZnxCu1-xS heterojunctions varied in the range from 2. 34 eV to 3. 51 eV. Hall test results demonstrate that when x values is less than 1, the ZnxCu1-xS composite films exhibit p-type semiconductor properties. Furthermore, increasing the proportion of CuS leads to an improvement in the conductivity of the composite films. Additionally, XPS results confirm that both Cu and Zn possess a + 2 valence within the composite films. When ZnxCu1-xS forms a heterojunction with porous n-GaN, the energy band structures of both materials interact to create a built-in electric field. This field facilitates the efficient separation of photogenerated electron-hole pairs. Finally, p-n heterojunctions UV detectors were constructed based on these heterostructures. The I-V curve results indicate that these detectors exhibit good rectification characteristics. Notably, the n-GaN/p-Zn0.4Cu0.6 S detector demonstrates optimal performance. In the dark state, I+3V/I-3V is approximately 1. 78 x 105. Under a bias voltage of - 3 V and an optical power density of 432 μW/cm² (ultraviolet light at 365 nm), this detector's photo-to-dark current ratio exceeds 103, the rise/fall time is 0.09/39.8 ms, responsivity(R) reaches 0. 352 A/W, the external quantum efficiency (EQE) stands at 119.6%, and detectivity(D*) is 3. 21 x 1012 Jones. The I-t curve results indicate that the porous n-GaN/p-ZnxCu1-xS heterojunctions UV detector possesses reproducible performance during the consecutive on-off optical cycling process with reproducible photocurrent response. This study offers valuable theoretical insights and a comprehensive understanding of the physical properties and performance characteristics of these novel heterostructures UV detectors. [ABSTRACT FROM AUTHOR]

As a new type of semiconductor material, halide perovskite materials has the advantages of low cost and excellent photoelectric conversion performance. Various photoelectric devices based on the halide perovskite materials have begun to be gradually applied. Polycrystalline thin films are still the main research direction, however, they have the disadvantages of disordered morphology and many impurities. In contrast, single crystals have the characteristics of no grain boundaries and low defects. Therefore, the research based on large-size single crystals gained widely concerned. In this paper, a set of internal and external reverse temperature control cycle filtration growth devices was designed. The CH3NH3PbBr3 single crystal with a diameter of more than 60 mm was prepared by the combination of inverse temperature crystallization and seed crystal. The phase, microstructure, and optical and electrical properties of the crystal samples were studied. The crystal belongs to the cubic system with space group of Pm3m. The ultraviolet-visible absorption spectrum shows that the absorption cut-off edge is about 576 nm and the fluorescence emission spectrum peak is 552 nm. The rocking curve shows that the half width at maximum of the crystal (100) plane is 91. 42". The wafer after cutting and polishing is sensitive to photo response, and the on-off ratio is 2. 4 x 104. [ABSTRACT FROM AUTHOR]

In recent years, semiconductor devices are developing towards high heat dissipation, high breakdown field strength and low energy consumption, so the ultra-wide band semiconductor material β-Ga2 O3 has a broad application prospect. However, effective doping is the basis for realizing β-Ga2 O3 devices. In this paper, Ga2O3/Al/Ga2O3/Al/Ga2O3 composite structure is experimentally prepared by magnetron sputtering, and the Al atoms are thermally diffused into the film by high-temperature annealing at the same time, so as to form Al-doped β-Ga2O3 thin film. Then, the laser zone melting method was used to melt and recrystallize the film area to further enhance the doping quality. The Al-doped β-Ga2O3 thin films were tested and characterized in terms of crystal properties, impurity content and optical properties. The experimental results show that: Al doping basically does not change the crystal structure of β-Ga2O3 thin films; the impurity content is gradually enhanced as the sputtering time of the Al layer becomes longer; in terms of the optical properties, the ultraviolet (UV) absorptivity of the films is 40% and 50% when the Al sputtering time is 5 and 10 s, and the UV absorption of the Al-doped β-Ga2O3 thin films is gradually enhanced with the increase of Al sputtering time; the light absorption of β-Ga2O3 thin film is close to 90% when the Al sputtering time is 300 s; and the low concentration of Al doping leads to the narrowing of the band gap width of β-Ga2O3 thin film. [ABSTRACT FROM AUTHOR]

Due to their unique physical and chemical properties, wide bandgap semiconductor materials have shown great potential in the field of optoelectronic devices, and have received more and more research and attention. Zinc gallate (ZnGa2O4) is a wide bandgap semiconductor material, showing broad application prospects in the fields of solar-blind ultraviolet photoelectric detection and X-ray detection for its wide bandgap, unique structure and good thermal stability. In this paper, based on the basic structural characteristics of ZnGa2O4, the bandgap, photoelectric properties of ZnGa2 O4, the preparation methods of ZnGa2O4 bulk single crystal and thin film are introduced in detail. Combined with the recent research results of domestic and foreign scholars, the application prospects of ZnGa2 O4 in many fields are summarized, especially the research progress of solar-blind ultraviolet photoelectric detection, memristor, X-ray detection and power devices. Finally, the future development direction of ZnGa2O4 is prospected, and it is pointed out that the quality and performance of ZnGa2O4materials can be further improved to improve device performance and meet higher level application requirements. [ABSTRACT FROM AUTHOR]

Due to their unique physical and chemical properties, wide bandgap semiconductor materials have shown great potential in the field of optoelectronic devices, and have received more and more research and attention. Zinc gallate (ZnGa2O4) is a wide bandgap semiconductor material, showing broad application prospects in the fields of solar-blind ultraviolet photoelectric detection and X-ray detection for its wide bandgap, unique structure and good thermal stability. In this paper, based on the basic structural characteristics of ZnGa2O4, the bandgap, photoelectric properties of ZnGa2 O4, the preparation methods of ZnGa2O4 bulk single crystal and thin film are introduced in detail. Combined with the recent research results of domestic and foreign scholars, the application prospects of ZnGa2 O4 in many fields are summarized, especially the research progress of solar-blind ultraviolet photoelectric detection, memristor, X-ray detection and power devices. Finally, the future development direction of ZnGa2O4 is prospected, and it is pointed out that the quality and performance of ZnGa2O4materials can be further improved to improve device performance and meet higher level application requirements. [ABSTRACT FROM AUTHOR]

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Copyright of Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To realize the on-line detection of pH value of heterogeneous systems and provide stable reference potential, the polydopamine modified Ag/AgCl solid film reference electrode was developed by magnetron sputtering deposition of silver film and chlorination of NaClO solution to obtain AgCl layer and dopamine deposition modification film. The stability, reversibility and cyclic voltammetry characteristics of polydopamine modified electrodes with deposition times of 4, 8, 12 and 16 h were compared in phosphate buffered saline (PBS) solution. The results show that the standard deviation of response potential of reference electrode in PBS solution is about 1.00 mV. It can recover to relatively stable potential in different pH buffer solutions, and the deviation of the reference electrode is less than 5.00 mV with good reversibility. The response potential drift is small in 50 cyclic voltammetry tests. According to the sensitivity of the reference electrode ranging from 2.00 to 2.50 mV/pCl, the polydopamine modified electrode is not sensitive to chloride ion concentration, which confirms that the polydopamine modified reference electrode is feasible. The reference electrode with deposition time of 12 h has the best comprehensive performance in various tests. The application tests illuminate that the reference electrode is more suitable for the detection of pH of cultivation substrate. [ABSTRACT FROM AUTHOR]

Copyright of China Rubber Industry is the property of Editorial Office of China Rubber Industry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Jilin University (Science Edition) / Jilin Daxue Xuebao (Lixue Ban) is the property of Zhongguo Xue shu qi Kan (Guang Pan Ban) Dian zi Za zhi She and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

(1 - x) CaBi4Ti4O15-xBi(Fe0.93Mn0.05Ti0.02)O3 (CBT-xBFMT, x = 0, 0.05, 0.10, 0.15) solid solution films were successfully prepared on Pt (111)/TiO2/SiO2/Si substrates using metal organic decomposition combined with spin coating technology. And the energy storage properties of CBT thin films were systematically studied by X-ray diffractometer, field emission scanning electron microscope, ferroelectric analyzer and impedance analyzer. The results show that the prepared films all exhibit a polycrystalline bismuth layered structure without other phase formation. The addition of BFMT into thin film obviously enhances the maximum polarization strength Pm and breakdown field strength Eb, reduces the leakage current density. With the increase of BFMT solid solution, the breakdown field strength Eb of CBT-xBFMT film increases first and then decreases, and reaches the maximum value at x = 0.10. The maximum polarization strength Pm gradually increases, and the largest polarization strength difference is obtained at x = 0.10. The largest polarization intensity difference and breakdown field strength make CBT-0.10BFMT film has the best energy storage properties. The recoverable energy storage density Wrec and energy storage efficiency η of CBT-0.10BFMT film are up to 82.8 J/cm³ and 78.3%, respectively. And its energy storage characteristic has good temperature stability in the temperature range of 25 ~ 150 °C. Therefore, CBT-0.10BFMT ferroelectric film is expected to be used in environmentally friendly micro energy storage devices. [ABSTRACT FROM AUTHOR]

Copyright of Laser Technology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

CdZnTe crystals are widely used as epitaxial substrates for HgCdTe thin films for infrared detectors and in the fabrication of room temperature nuclear radiation detectors. During crystal growth, the interface shape is closely related to the heat state. Combined with the numerical simulation technique to control the temperature field distribution during CdZnTe crystal growth, the crystal growth procedure of micro-convex solidification interface by vertical Bridgman method and vertical gradient freeze method were designed, and the single crystal rate of CdZnTe crystals was analyzed according to the actual crystal growth experiments. The distribution spectrum of Zn components in the longitudinal section of CdZnTe crystals with equal diameters was obtained by photoluminescence spectroscopy for compositional testing in order to investigate the relationship between the temperature field distribution at the solid-liquid interface and the macroscopic segregation behavior of Zn components. It is found that the temperature gradient distribution on both sides of the solid-liquid interface significantly influences the shape selection and stability of the solidification interface during the crystal growth process, and a larger temperature gradient on the solid-phase side contributes helps to achieve stable crystal growth at the convex interface, thereby increasing the likelihood of growing single crystals. [ABSTRACT FROM AUTHOR]

Copyright of Laser Technology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Starch is a natural polymer material composed of α-glucose molecules with a wide range of sources, and mainly in the roots and stems of plants. It is inexpensive, renewable and biodegradable. The preparation of natural degradable plastic films from starch is of great significance to solve the problem of environmental pollution. Compared with starch-based materials, synthetic thermoplastic polymers such as polyethylene, polypropylene and polystyrene have disadvantages such as irritating odor, non-biodegradable and polluting the environment. Biodegradable thermoplastic materials made from starch have become a hot research topic for researchers. In this paper the structure and properties of starch is described, together with the plasticization methods, the ways to improve the barrier and mechanical properties of thermoplastic starch. Also the research progress and the outlook of thermoplastic starch-based materials are summarize. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Liquid Crystal & Displays is the property of Chinese Journal of Liquid Crystal & Displays and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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The application of thin film pretreatment technology in automobile painting was introduced. The cause of "crop circle" defect occurring during electrocoating after thin film pretreatment was analyzed. Some solutions were discussed. The problem was solved by improving the spray cleaning before and after electrocoating, increasing the concentration of sulfamic acid in electrocoating tank, and optimizing the production line running speed in electrocoating section. [ABSTRACT FROM AUTHOR]

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The model of copper-antimony-sulfur (CuSbS2) thin film solar cell was constructed, and the performance of the device was calculated by SCAPS. The effects of absorption layer thickness, carrier concentration, defect density, and back contact work function on the device performance were investigated. The results show that the green and red light are not fully absorbed by too thin absorption layer, and the absorption layer with the thickness of 1. 5 μm to 3 μm can meet spectral absorption requirements. When the acceptor concentration is 2 ×1018 cm-3, the photoelectricity conversion efficiency (PCE) of the device is the highest. When the defect density is larger than 10 -14 cm-3, the PCE of the device decreases sharply. CuSbS2 prepared in a copper-poor and sulfur-rich atmosphere can increase the accepter concentration, reduce the open circuit voltage defect, and inhibit the formation of sulfur vacancy defects, thus improving the PCE of the device. High work function materials can decrease the back contact barrier and reduce carrier recombination. After the material parameters have been optimized, the highest PCE of the device is 21. 74%. [ABSTRACT FROM AUTHOR]

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Copyright of Oilfield Chemistry is the property of Sichuan University, Oilfield Chemistry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, a series of ITO thin films with different concentrations of metal Sn doping were prepared by electron beam evaporation technique. X-ray diffractometer, atomic force microscope, UV-Vis-NIR spectrophotometer, four-probe resistivity meter and Z-scan system were used to measure and characterize the physical phase structure, microscopic morphology, optical absorption, square resistance and nonlinear optical properties of ITO films, respectively. The test results show that, with the increase of metal Sn doping concentration from 10% to 30%: the crystalline quality of the ITO film is enhanced; the surface roughness of the film increases and the grain size gradually increases; the plasma absorption is enhanced and the position of the absorption peak is red-shifted and the optical band gap is narrowed; the square resistance of the film continuously reduces; the nonlinear absorption coefficient gradually increases, and the maximum absolute value can be increased to 2.59 × 10-7 cm/ W. The finite-difference fitting results in the time domain show that the variation pattern of electric field intensity of ITO thin film samples with different metal Sn doping concentrations is consistent with the experimental results. [ABSTRACT FROM AUTHOR]

Porous GaN thin films were successfully prepared by high-temperature annealing of GaN thin films with Au nanoparticles deposited on their surfaces in H2 and N2 atmosphere. The surface morphology of the porous structure can be regulated by parameters such as annealing temperature, annealing time and Au deposition time. The crystal quality of different GaN structures was characterized by high-resolution X-ray diffraction (HRXRD) and Raman spectroscopy. Compared with planar GaN, the dislocation density and residual stress of porous GaN are reduced. When the annealing temperature is 1 000 ℃, the dislocation density is the lowest and more compressive stress is released. The optical properties of the porous GaN were characterized by photoluminescence (PL) spectroscopy. Compared with planar GaN, the luminous intensity of porous GaN is significantly improved, which can be attributed to the increased porosity of the porous structure, and therefore effectively increased light scattering. In addition, the photocurrent density of different GaN structures was tested by electrochemical work station, and the results confirm that the photocurrent density of porous GaN with larger specific surface area can be increased by about 1. 67 times when used as a working electrode. Porous GaN thin films through high-temperature etching are successfully prepared in this paper, which providing some theoretical guidance for the improvement of the crystal quality and optical properties of the GaN epitaxial layer, and also shed some light on its application in the fields of photoelectric catalysis. [ABSTRACT FROM AUTHOR]

Copyright of Automobile Technology & Material is the property of Automobile Technology & Material Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal Of Sichuan University (Natural Sciences Division) / Sichuan Daxue Xuebao-Ziran Kexueban is the property of Editorial Department of Journal of Sichuan University Natural Science Edition and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work, Cu and Cu55Ni45 thin films with a thickness of 600 nm were firstly deposited on single crystal Si and Al2O3 ceramic substrates by magnetron sputtering respectively. Then, the thin film thermopiles composed of 200 pairs of in-series thermocouples were fabricated by microfabrication technology in 10 mm x 10 mm substrate area. Finally, aluminum oxide layers were deposited by reactive magnetron sputtering as thermal resistance layers, with the help of hard mask. The different thickness of the aluminum oxide layer produces the cold and hot ends in the thin film thermopile, giving rise to a voltage under the irradiation of heat flux by the Seebeck effect, realizing the measurement of heat flux. The thin film thermopiles were analyzed and calibrated. The results show that in the Cu/Cu55Ni45 thermopiles deposited on the Si substrate and Al2O3 ceramic substrate, the roughness of the Cu films are 20 and 60 nm, the roughness of Cu55Ni45 films are 15 and 20 nm, the electrical resistance of thermopiles are 38. 2 Ω and 2. 83 kΩ, the sensitivity of thermopiles are 0. 069 45 and 0.026 97 mV/(kW ⋅ m-2), respectively. The surface roughness of Cu/Cu55Ni45 thermopiles deposited on single crystal Si substrate and Al2O3 ceramic substrate with different surface roughness will be affected, resulting in the difference in electrical resistance of thin film thermopile. In addition, the output thermoelectric voltage exhibits a good linear relationship with heat flux. [ABSTRACT FROM AUTHOR]

Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Thienoacenes are a representative class of high mobility organic semiconductor materials (OSCs). Asymmetric molecules based on them tend to form a bilayer arrangement in thin films and grow in a twodimensional layer-like manner, which has the advantage of achieving high mobility. The length of the alkyl substituents affects the packing microstructure of OSCs. Herein, thieno [4, 5-b] [1] benzothieno [3, 2-b] [1] benzothiophenes substituted with different lengths of alkyl chains (syn-BTBTT-Cn, n=4, 5, 6, 7, 8, 10) are designed and synthesized to systematically investigate the effects of lengths of alkyl chains on their thermal stability, energy levels, charge carrier transport capabilities, packing structures and film morphologies. All compounds are thermally stable and do not have liquid crystalline behaviors. All molecules in the vacuumdeposited films form a bilayer arrangement, within the conjugated cores forming a herringbone packing motif, and the alkyl chain length affects the film order and the tightness of the packing. Organic thin. film transistors devices all exhibit mobilities beyond 7. 0 cm² (/ V·s). Among them, the syn-BTBTT-C8 devices show a mobility of up to 13. 8 cm² (/ V·s) with the average values of 12. 5 cm² (/ V·s). [ABSTRACT FROM AUTHOR]

In long-term outdoor operation, both crystalline silicon solar cells and thin film solar cells are subject to potential-induced degradation (PID), decreasing the output power of photovoltaic modules. Despite numerous studies in the past, the understanding of the PID phenomenon and its solutions is still incomplete. In order to promote a deeper understanding of the PID phenomenon in solar cells and provide guidance for stability research of solar cells, the causes of PID in crystalline silicon solar cells and thin film solar cells, as well as related solutions are reviewed in this paper. [ABSTRACT FROM AUTHOR]

In this work, single-crystal gallium oxide (β-Ga2O3 ) thin films were epitaxially grown on different off-cut angled c-plane sapphire substrates by metal organic chemical vapor deposition (MOCVD), and the effect of off-cut angles on the crystal quality and surface roughness of the epitaxial films were investigated. For the β-Ga2O3 epilayer grown on the 6° off-cut angled sapphire substrate, the full width at half maximum (FWHM) of the rocking curve is reduced to be 1.10°, together with the smallest surface roughness of 7.7 nm. Consequently, the metal-semiconductor-metal structured solar-blind ultraviolet photodetectors were fabricated by lithography, development, electron beam evaporation and lift-off techniques. The photodetector has excellent performances, including photo-dark current ratio of 6. 2 × 106, peak photoresponsivity of 87. 12 A/ W at 248 nm, specific detectivity of 3. 5 ×1015 Jones, UV-visible rejection ratio of 2. 36 ×104, and total response time of 226. 2 μs. [ABSTRACT FROM AUTHOR]

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Covalent organic frameworks (COFs), a new type of crystalline porous materials, have attracted considerable attention in many fields such as separation, catalysis, drug release, and optoelectronics. The crystallinity and morphology of COFs determine their application. In this study, the synthetic methods and applications of COFs with different morphologies (spherical, thin film, rod, tubular, fibrous, belt, cage, and roll) are reviewed. Existing problems are also discussed and their potential solutions are proposed. [ABSTRACT FROM AUTHOR]

Remote epitaxy is an emerging technology for producing single-crystalline, free-standing thin films and structures. The method uses 2D van der Waals materials as semi-transparent interlayers that enable epitaxy and release of epitaxial layers at the 2D layer interface. The use of single-layer graphene as the interlayer for heterogeneous remote epitaxial GaN nucleation layer and GaN film on the sapphire substrate was studied. The result shows that GaN nucleation island has a good orientation. Through parameter adjustment, a dense GaN nucleation layer was obtained. AFM observation and XRD detection confirm that GaN thin film has lower surface roughness and dislocation density compared with film that grow directly on sapphire substrate under the same conditions. The existence of graphene after growing GaN film was confirmed by Raman spectra. [ABSTRACT FROM AUTHOR]

With the widespread application of gallium nitride (GaN) in the high-power field, the heat dissipation of GaN based devices has become the main factor restricting the power density. Therefore, it is crucial to develop novel thermal management solutions. Diamond substrates with high thermal conductivity can be used to improve the heat dissipation of GaN devices. However, due to the natural lattice mismatch between diamond and GaN, the direct epitaxy of GaN on diamond substrates remains an insurmountable problem. This work achieved van der Waals epitaxy of single crystal GaN films on polycrystalline diamond substrates using a two-dimensional material / Al gradient AlGaN heterostructure as the nucleation layer between the substrate and the epitaxial layer. Among them, two-dimensional materials can effectively shield against the adverse effects caused by lattice mismatch between the substrate and epitaxial layer, while the Al component gradient AlGaN buffer layer can achieve orderly migration of Ga and N atoms, thereby accurately controlling the growth of GaN thin films. This work provides a novel approach for high-quality growth of nitrides on heterogeneous substrates. The experimental results indicate that the introduction of nucleation layers effectively eliminates the impact of lattice mismatch, thereby breaking the bottleneck of the difficulty in directly epitaxial single crystal GaN films on diamond substrates. This work provides a foundation for further improving the power density of GaN based devices. [ABSTRACT FROM AUTHOR]

As an ultrawide band gap semiconductor, two-dimensional (2D) hexagonal boron nitride ( h-BN) has attracted considerable research interest because of its unique properties such as excellent electrical insulation, high breakdown field, high thermal conductivity, and good chemical inertness, which make it a promising candidate as dielectric and substrate layers for devices based on other 2D materials. The synthesis of high-quality and large-area h-BN layers with few defects is strongly desirable for these applications. In this review, the methods and progress of the epitaxial growth of 2D h-BN on transition metal, h-BN films on dielectric and semiconductor substrates are described in detail. The high-quality 2D h-BN layers can be epitaxially grown on the transition metal substrates with catalytic activity including Cu, Ni, Fe, Pt, etc. However, it is a great challenge to directly grow h-BN single crystal films on insulating dielectric or semiconductor substrates. Sapphire is a preferred substrate for the growth of h-BN for its good thermal stability and chemical stability. The growth of h-BN thin films on sapphire substrate has been widely reported by various techniques, such as chemical vapor deposition, molecular beam epitaxy, ion beam sputtering deposition, metal-organic vapor phase epitaxy, high-temperature post-annealing and so on. Based on these techniques, high-quality 2D h-BN has been prepared on sapphire substrates, it can also be integrated into the epitaxial growth processes of some existing III-V compound semiconductors, laying the foundation for the large-scale application of h-BN. In addition, the growth of h-BN single crystal films have also been attempted on semiconductor substrates like graphene, silicon and germanium, which provide an attractive strategy for the fabrication and application of h-BN-based heterojunctions. [ABSTRACT FROM AUTHOR]

Fluorescent anti-counterfeit printing technology is applied in the special fluorescent printing ink used for logos, which in conjunction with additional light excitation to expose the encrypted information play an anticounterfeiting role. Fluorescent anti-counterfeiting is mostly used in film or solid state; therefore, it is necessary for fluorescent ink to have strong luminescent properties in both states. Aggregation-induced emission (AIE) molecules are a class of molecules that emit weak or even no light in a single molecule state and exhibit strong luminescence in an aggregated state. As a typical AIE molecule with simple synthesis and high fluorescence intensity, the salicylaldehyde Schiff base molecule has a stimulus-responsive fluorescence mechanism. Its different fluorescence characteristics in acid-base environments make this kind of molecule outstanding in the field of anti-counterfeit printing. In this study, the salicylaldehyde Schiff base AIE molecule was prepared by a one-step nucleophilic addition reaction of salicylaldehyde and amine, and its application in anti-counterfeit printing was further demonstrated. Through the characterization of the molecule in different environments, the role of its AIE characteristics and stimulus response fluorescence mechanism in anti-counterfeit printing applications was elucidated. The experimental raw materials are easy to obtain, safe, low cost, and the required instruments are routine, which meets the requirements of laboratory teaching. Through this experimental training, students not only master the preparation method of Schiff base compounds, but also learn the application of stimulus response fluorescence of salicylaldehyde Schiff base molecules in anti-counterfeit printing. The combination of classroom teaching and extended reading, enables students to further understand the characteristics of anti-counterfeit printing products and design concepts. [ABSTRACT FROM AUTHOR]

In this paper, the R-cut sapphire single crystal substrates were selected, and the CeO2 buffer layers were grown on the surfaces of substrates by RF magnetron sputtering method, then the high quality Tl-1223 superconducting films were grown by the rapid heating-up sintering technology. The effects of buffer layer growth and post annealing conditions of the precursor films on the crystallization and superconducting properties of the superconducting thin films were studied. AFM and XRD measurements show that the surface of sapphire substrates have a step structure with smooth platform and the crystal quality of sapphire substrates have been improved after annealing; the CeO2 buffer layers and the Tl-1223 superconducting films all have good c-axis growth orientation under appropriate parameters, and they exist a good ab-plane texture. SEM measurements show that the well grown Tl-1223 superconducting films have a layered structure and their surfaces are dense and smooth. The Tc of the prepared superconducting film is measured to be about 111 K, and Jc (77 K, 0 T) is measured to be about 1. 3 MA/cm² in liquid nitrogen environment. [ABSTRACT FROM AUTHOR]