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41.
Single‐source organometallic precursors based on a number of homometallic clusters as well as heterometallic cluster RuOs3(CO)13(µ‐H)2 have been used for the chemical vapor deposition of osmium films and osmium–ruthenium alloy films, respectively. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Jagdeep S. Sagu K.G. Upul Wijayantha Paul Holland Mallika Bohm Siva Bohm Tapan Kumar Rout Hemaka Bandulasena 《Crystal Research and Technology》2016,51(8):466-474
Carbon emissions from industrial sources are of major global concern, especially contributions from the steel manufacturing process which accounts for the majority of emissions. Typical blast furnace gases consist of CO2 (20‐25%), CO (20‐25%), H2 (3‐5%) and N2 (40‐50%) and trace amounts of other gases. It is demonstrated that gas mixtures with these compositions can be used at atmospheric pressure to grow carbon nanotubes (CNTs) by chemical vapor deposition (CVD) on to steel substrates, which act as catalysts for CNT growth. Computational modelling was used to investigate the CNT growth conditions inside the CVD chamber. The results show that industrial waste pollutant gases can be used to manufacture materials with significant commercial value, in this case CNTs. 相似文献
44.
Mahrokh Elyassi Alimorad Rashidi Mohammad Reza Hantehzadeh Seyed Mohammad Elahi 《Surface and interface analysis : SIA》2017,49(4):230-237
In this study, different types of graphene were synthesized to investigate hydrogen adsorption capacity at different pressures (0–34 bar) at room temperature (298 K). Graphene and nanoporous graphene were prepared by Chemical Vapor Deposition (CVD) method, using methane as a carbon source at a temperature of 900 °C over copper plates and nickel oxide nanocatalyst. The nickel oxide nanocatalyst was prepared by sol–gel method, whereas graphene oxide was prepared through modified Hummer's method. The products were characterized by X‐ray diffraction, field emission‐scanning electron microscopy, energy dispersive spectroscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller and Raman spectroscopy. The adsorption of hydrogen was done by volumetric method. High adsorption capacity was achieved in nanoporous graphene because of its high pore volume (2.11 cm3/g) and large specific surface area (850 m2/g). Hydrogen adsorption values for nanoporous graphene, graphene and graphene oxide were determined as 2.56, 1.70 and 0.74 wt%, respectively. In addition, the hydrogen adsorption of graphene nanostructures fitted nicely to the selected two‐parameter and three‐parameter adsorption isotherm models. The adsorption isotherm model coefficients have been found for a 0–34 bar pressure range. The parameter values for all adsorbents showed proper conformity to the model and experimental data. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
45.
Rached Salhi Ramzi Maalej Yannick Guyot Laetitia Rapenne Jean-Luc Deschanvres 《Journal of luminescence》2011,131(11):2311-2316
Erbium-doped Y2O3 films were prepared by aerosol-UV assisted metal-organic chemical vapour deposition (MOCVD) at 410 °C. The effects of humidity of carrier gas and UV-assistance on their structure and optical properties were investigated on the as-deposited and thermal annealed films using infrared spectroscopy, X-ray diffraction and transmission electron microscopy. It was found that the as-deposited Er:Y2O3 films crystallise in the Y2O3 cubic structure and present a very low organic contamination when the deposition takes place under high air humidity and, even better, with UV-assistance. After annealing, two different structural phases are observed corresponding to the cubic and the monoclinic structures of Y2O3. The Er3+ luminescence analysed in the visible and IR regions, shows the classical green transitions. The best optical properties were obtained with as-deposited and annealed Er:Y2O3 films grown under high air humidity with UV-assistance. Under such deposition conditions, 4I13/2 lifetimes was found to be 3.07 and 6.1 ms for films annealed at 800 and 1000 °C, respectively, and up-conversion phenomena were underlined. This indicates that the deposition conditions, in particular air humidity, play an important role in the luminescent properties even after annealing. 相似文献
46.
借助二次模板法成功的合成了AlN纳米线宏观阵列,并进行了表征.主要研究CVD法制备有一定取向,直径均匀的AlN纳米线宏观阵列的过程.通过气相沉积法和利用PS球自组装模板制备了金属纳米颗粒模板;再以模板上的金属纳米颗粒作为催化剂,利用化学气相沉积在模板上合成AlN纳米线宏观阵列.借助SEM,TEM观察所得样品,AlN纳米线阵列面积约为0.3 mm×0.2 mm,直径和长度分布均匀,平均直径约为41 nm,平均长度为1.8 μm左右,分散密度和覆盖率大的六角结构AlN纳米线宏观阵列.得到了可控制备AlN纳米线
关键词:
AlN纳米线阵列
模板法
CVD法
SEM 相似文献
47.
Nano-sheet carbon films (NSCFs) coated with very thin (≈5-nm-thick) metal layers were fabricated on Si wafer chips by means of quartz-tube-type microwave-plasma chemical-vapour-deposition method with hydrogen-methane gas mixture and an electron beam evaporation method. Field emission (FE) current densities obtained at a macroscopic average electric field, E, of ≈10 V/μm changed from 13 mA/cm2 for NSCF with no coated metal to 1.7, 0.7 and 30 mA/cm2 for Ti-, Al- and Au-coated NSCFs, respectively, while the threshold E varied from 4.4 V/μm for the former one to 5.3, 5.4 and 2.0 V/μm for the corresponding latter ones, respectively. As the FE currents of Au-coated NSCFs tended to be saturated in a higher E region, compared to those of NSCFs with no coated metal, no simple Fowler-Nordheim (F-N) model is applicable. A modified F-N model considering statistic effects of the FE tip structures and a space-charge-limited-current effect is successfully applied to an explanation for the FE data observed in the low and high E regions. 相似文献
48.
Volodymyr D. Khavryuchenko Oleksiy V. Khavryuchenko Vladyslav V. Lisnyak 《固体与材料科学评论》2011,36(2):47-65
This article describes the genesis of amorphous silica under high-heat conditions from SiO2 molecules through protoparticles, primary particles, and aggregates to agglomerates using vibrational spectra and quantum chemical simulations data. The impact of small molecules (water, HCl, CO2) is also discussed. The article also explains the nature of the pyrogenic silica amorphism. 相似文献
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50.
Hui Zeng Yao Wen Lei Yin Ruiqing Cheng Hao Wang Chuansheng Liu Jun He 《Frontiers of Physics》2023,18(5):53603
Two-dimensional (2D) transition metal dichalcogenides (TMDs) with fascinating electronic energy band structures, rich valley physical properties and strong spin–orbit coupling have attracted tremendous interest, and show great potential in electronic, optoelectronic, spintronic and valleytronic fields. Stacking 2D TMDs have provided unprecedented opportunities for constructing artificial functional structures. Due to the low cost, high yield and industrial compatibility, chemical vapor deposition (CVD) is regarded as one of the most promising growth strategies to obtain high-quality and large-area 2D TMDs and heterostructures. Here, state-of-the-art strategies for preparing TMDs details of growth control and related heterostructures construction via CVD method are reviewed and discussed, including wafer-scale synthesis, phase transition, doping, alloy and stacking engineering. Meanwhile, recent progress on the application of multi-functional devices is highlighted based on 2D TMDs. Finally, challenges and prospects are proposed for the practical device applications of 2D TMDs. 相似文献