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Synthesis of Bismuth Ferrite BiFeO <sub/>3</sub> by solution combustion method
摘要： In this work we describe the synthesis of bismuth ferrite BiFeO3 (BFO) by the method of combustion in solution. Using the techniques of X-ray diffraction (XRD) together with its refinement Rietveld reveals the existence of a distorted rhombohedral perovskite structure (Space group-R3c). The average size of the BFO crystallite was estimated from the half-height width of the X-ray diffraction peaks using the Scherrer’s equation. The morphology of the prepared sample was determined by scanning electron microscopy (SEM) and stoichiometry ratio of BFO was determined by energy dispersive spectroscopy (EDS)
关键词： BFO,X-Ray Diffraction (XRD),Combustion synthesis,Multiferroics
更新于2025-09-23 15:23:52
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Effect of low-energy ion impact on the structure of hexagonal boron nitride films studied in surface-wave plasma
摘要： A high‐density surface‐wave plasma source is used to deposit hexagonal boron nitride (hBN) films in a gas mixture of He, H2, N2, Ar, and BF3 under a high ion flux condition using low‐energy ion irradiation. The ion energy is controlled between around zero and 100 eV by applying a negative or positive bias voltage to a substrate, while the ion flux is increased by locating a substrate upstream in the diffusive plasma. For ion energies above ～37 eV, the structure of the films depends upon ion energy more than substrate temperature, typical of subplantation processes. As a result, the structural order and crystallinity of sp2‐bonded phase in the films characterized by Fourier transform infrared spectroscopy and X‐ray diffraction are increased with decreasing ion energy, while the mass density of the films characterized by X‐ray reflectivity is retained relatively high with a slight dependence upon ion energy.
关键词： surface‐wave plasma,Fourier transform infrared spectroscopy (FTIR),chemical vapor deposition (CVD),hexagonal boron nitride (hBN),X‐ray diffraction (XRD),X‐ray reflectivity (XRR)
更新于2025-09-23 15:21:21
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High Responsivity Visible Blind Pd/Al2O3/MoS2/ITO MISM UV Photodetector
摘要： In the present paper, Pd/Al2O3/MoS2/ITO MISM UV photodetector structure is proposed and analyzed. For the proposed photodetector, responsivity is 488 A/W, detectivity is 8.22×1013Jones and external quantum efficiency (EQE) is 1.9×105%, at wavelength 308nm, 1V bias and light intensity 13.6μW/cm2. Thus, proposed MISM photodetector device gives significant performance improvement over other UV photodetectors.
关键词： Molybdenum di-sulphide (MoS2),Responsivity,Photodetector,X-ray diffraction (XRD)
更新于2025-09-23 15:21:01
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Studies on structural, surface morphology and optical properties of Zinc sulphide (ZnS) thin films prepared by chemical bath deposition
摘要： Zinc sulphide (ZnS) thin films have been prepared by chemical bath deposition method. X-ray diffraction (XRD) is used to analyze the structure and crystallite size and scanning electron microscopy is used to study the particle size and morphology of ZnS thin film. Optical studies have been carried out using UV-Visible-NIR absorbance spectrum. The band gap value of the film is calculated and it is found to be 3.45 eV. The dielectric properties of ZnS thin films have been studied in the different frequency at different temperatures.
关键词： scanning electron microscopy (SEM),Zinc sulphide (ZnS) thin films,dielectric studies,X-ray diffraction (XRD)
更新于2025-09-23 15:19:57
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Strain Mapping of CdTe Grains in Photovoltaic Devices
摘要： Strain within grains and at grain boundaries (GBs) in polycrystalline thin-film absorber layers limits the overall performance because of higher defect concentrations and band fluctuations. However, the nanoscale strain distribution in operational devices is not easily accessible using standard methods. X-ray nanodiffraction offers the unique possibility to evaluate the strain or lattice spacing at nanoscale resolution. Furthermore, the combination of nanodiffraction with additional techniques in the framework of multimodal scanning X-ray microscopy enables the direct correlation of the strain with material and device parameters such as the elemental distribution or local performance. This approach is applied for the investigation of the strain distribution in CdTe grains in fully operational photovoltaic solar cells. It is found that the lattice spacing in the (111) direction remains fairly constant in the grain cores but systematically decreases at the GBs. The lower strain at GBs is accompanied by an increase of the total tilt. These observations are both compatible with the inhomogeneous incorporation of smaller atoms into the lattice, and local stress induced by neighboring grains.
关键词： X-ray microscopy,nanodiffraction,X-ray diffraction (XRD),solar cells,multimodal,CdTe,X-ray,strain,X-ray fluorescence (XRF),photovoltaic,X-ray beam induced current (XBIC)
更新于2025-09-19 17:13:59
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Strategy of Residual Stress Determination on Selective Laser Melted Al Alloy Using XRD
摘要： Selective laser melting (SLM) is known to generate large and anisotropic residual stresses in the samples. Accurate measurement of residual stresses on SLM-produced samples is essential for understanding the residual stress build-up mechanism during SLM, while a dramatic fluctuation can be observed in the residual stress values reported in the literature. On the basis of studying the influence of surface roughness on residual stress measured using X-ray diffraction (XRD), we propose a procedure coupling XRD technique with pretreatment consisting of mechanical polishing and chemical etching. The results highlight that residual stresses measured using XRD on as-built SLM-produced samples with high surface roughness are significantly lower than those measured on samples with finished surface, which is due to the stress relaxation on the spiked surface of as-built samples. Surface distribution of residual stresses and the effect of scanning strategy were systematically investigated for SLM-produced AlSi10Mg samples. Microstructural morphology was observed at the interface between sample and building platform and was linked to the surface distribution of residual stresses. This procedure can help us accurately measure the residual stresses in SLM-produced samples and thus better understand its build-up mechanism during the SLM process.
关键词： X-ray diffraction (XRD),residual stresses,AlSi10Mg,selective laser melting,surface roughness
更新于2025-09-19 17:13:59
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Effect of Temperature of Electron Beam Evaporated CdSe Thin Films
摘要： CdSe thin films were deposited on a glass substrate by using electron beam evaporation technique. The as deposited films were annealed from 100oC to 300°C with an increment of 100°C. Morphological, structural and optical characterization of the films was carried out by using scanning electron microscope (SEM), X-ray diffraction (XRD), ultraviolet-visible (UV-Vis) spectroscopy; and Fourier transform infrared spectroscopy. The X-ray diffraction pattern that the film has a cubic phase with preferred orientation (100), the grain size was found to be in the range of 29-46 nm. SEM results reveal that film grains are polycrystalline in nature covered the whole surface of the substrate.
关键词： FTIR,CdSe thinfilm,Scanning electron microscope,X-ray diffraction (XRD)
更新于2025-09-10 09:29:36
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Determination of Sulfite in Botanical Medicine Using Headspace Thin-Film Microextraction and Surface Enhanced Raman Spectrometry
摘要： A facile method using headspace thin-film microextraction (HS-TFME) coupled with surface enhanced Raman spectrometry (SERS) has been developed for the determination of sulfite in traditional Chinese herbal medicine. The extraction substrate was synthesized by depositing urchin-like ZnO micron particles on glass sheets using chemical liquid phase deposition. Under the optimal conditions, the intensity of the SERS signal at 630–640 cm?1 provided a good linear relationship with the concentration of sulfite from 25 to 400 mg/kg, and the linear correlation coefficient (R) was 0.996 with a detection limit of 6 mg/kg. The method was employed for the determination of sulfite in herbal medicines, and the results were confirmed by a traditional distillation-titration method. Therefore, this developed HS-TFME-SERS method may play an important role in the rapid, simple, and selective determination of sulfite residues in Chinese herbal medicine and become a potentially universal method for this analyte in various solid samples.
关键词： Headspace thin-film microextraction (HS-TFME),scanning electron microscopy (SEM),X-ray diffraction (XRD),surface enhanced Raman spectrometry (SERS),transmission electron microscopy (TEM)
更新于2025-09-10 09:29:36
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Analysis of the inhomogeneous barrier and phase composition of W/4H-SiC Schottky contacts formed at different annealing temperatures
摘要： The electrical characteristics of W/4H-SiC Schottky contacts formed at different annealing temperatures have been measured by using current–voltage–temperatures (I–V –T ) and capacitance–voltage–temperatures (C–V –T ) techniques in the temperature range of 25 ?C–175 ?C. The testing temperature dependence of the barrier height (BH) and ideality factor (n) indicates the presence of inhomogeneous barrier. Tung’s model has been applied to evaluate the degree of inhomogeneity, and it is found that the 400 ?C annealed sample has the lowest T0 of 44.6 K among all the Schottky contacts. The barrier height obtained from C–V –T measurement is independent of the testing temperature, which suggests a uniform BH. The x-ray diffraction (XRD) analysis shows that there are two kinds of space groups of W when it is deposited or annealed at lower temperature ((cid:54) 500 ?C). The phase of W2C appears in the sample annealed at 600 ?C, which results in the low BH and the high T0. The 500 ?C annealed sample has the highest BH at all testing temperatures, indicating an optimal annealing temperature for the W/4H-SiC Schottky recti?er for high-temperature application.
关键词： inhomogeneity barrier,SiC,Schottky contact,x-ray diffraction (XRD)
更新于2025-09-09 09:28:46
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Studies on zinc oxide thin films by chemical spray pyrolysis technique
摘要： Zinc oxide (ZnO) thin films were deposited by chemical spray pyrolysis (CSP) technique using zinc acetate dihydrate solutions on microscopic glass substrates by varying the precursor concentration. The prepared films were characterized structurally and optically, using the powder X-ray diffraction (XRD) and UV analysis and Photoluminescence analysis. Crystallographic properties were analyzed through powder XRD. The XRD patterns shows a hexagonal structure with c-axis orientation (0 0 2) on self texturing phenomenon. Optical transmittance properties of the optimized ZnO thin films were investigated by using UV-Vis spectroscopy. The optical studies predicated a maximum transmittance in the range of above 70% with direct band gap values in the range of 2.9 to 3.2eV for the zinc oxide thin films. Under excitation of 300 nm radiations, sharp deep level emission peak at 2.506 eV dominates the photoluminescence spectra with weak deep level and near band edge emission peak at 3.026 and 3.427 eV respectively.
关键词： Photoluminescence,Transparent conducting oxide (TCO),UV-Vis,Zinc Oxide thin film,CSP technique,X-ray diffraction (XRD)
更新于2025-09-09 09:28:46