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141.
In this paper, an N-doped titanium oxide (TiO2) photocatalyst is deposited by a plasma-enhanced atomic layer deposition (PEALD) system through the in-situ doping method. X-ray photoelectron spectroscopy (XPS) analysis indicates that substitutional nitrogen atoms (-395.9 eV) with 1 atom% are effectively doped into TiO2 films. UV-VIS spectrometry shows that the in-situ nitrogen doping method indeed enhances the visible-activity of TiO2 films in the 425-550 nm range, and the results of the performance tests of the N-doped TiO2 films also imply that the photocatalysis activity is improved by in-situ doping. The in-situ doping mechanism of the N-doped TiO2 film is suggested according to the XPS results and the typical atomic layer deposition process. 相似文献
142.
143.
通过对宝钢厂区大气环境主要污染物监测数据的整理,综合分析了宝钢厂区大气环境中二氧化硫、氮氧化物、可吸入颗粒物(PM10)和一氧化碳四种主要污染物的平均浓度随季节的变化趋势以及厂区内降尘的污染状况,并对2008年大气环境质量状况进行了综合评价。分析对比结果表明宝钢内大气主要污染因子是PM10和SO2,从监测资料看,2008年厂区降尘量比2007年有了明显下降,SO2和NOx的达标率均呈现上升趋势,可见宝钢在粉尘和脱硫脱氮治理方面取得了显著效果,污染程度明显下降。 相似文献
144.
《等离子体科学和技术》2020,22(9):94013
The highest deposition of power and temperature is always near the cusp of the ATON-type Hall thruster. This shows that when there are electrons gathering at the cusp, the distribution of heat load will be uniform, which will potentially damage the reliability. Therefore, we optimize the magnetic field near the anode. We changed the magnetic field characteristics in the near-anode region with an additional magnetic screen, and performed numerical simulation with particle-incell simulation. The simulation results show that the magnetic field of the thruster with the additional magnetic screen can alleviate the over-concentration of power deposition on the anode and reduce the power deposition in the anode by 20%, while ensuring that the overall magnetic field characteristics do not change significantly. 相似文献
145.
Aluminum-doped zinc oxide films (ZnO:Al) were deposited on Si wafers and glass substrates by dc magnetron sputtering from a ZnO target mixed with 2 wt% Al2O3 for photovoltaic films. The effect of base pressure, additional oxygen, and substrate temperature were studied in detail. By dc magnetron sputtering at room temperature, the resistivity and the average transmittance in visible range was 2.3 × 10−3 Ω cm and 77.3%, respectively. And these were improved up to 3.3 × 10−4 Ω cm and 86% at the substrate temperature of 400 °C by high deposition rate and low impurity ambient. The mobility and the carrier concentration were improved by the increased preferred orientation of (002) plane and grain size of film with increasing deposition temperature. This advanced AZO film with good resistivity and transmittance can be expected as the front TCO of thin film solar cells. 相似文献
146.
Fumiaki Mitsugi Yoshihiro Umeda Norihiro Sakai Tomoaki Ikegami 《Thin solid films》2010,518(22):6334-1307
Recently, transparent conducting oxide thin films have attracted attention for the application to transparent conducting electrodes. In this work, we evaluated the uniformity of electrical, optical and structural properties for gallium doped zinc oxide thin films prepared on the 10 × 10 cm2 silica glass substrate by pulsed laser deposition. The resistivity, carrier concentration, mobility, bonding state and atomic composition of the film were uniform along in-plane and depth direction over the 10 × 10 cm2 area of the substrate. The film showed the average transmittance of 81-87%, resistivity of 1.4 × 10− 3 Ω cm, carrier concentration of 9.7 × 1020/cm3 and mobility of 5 cm2/Vs in spite of the amorphous X-ray diffraction pattern. The gradual thickness distribution was found, however, the potential for large-area and low temperature deposition of transparent conducting oxide thin film using pulsed laser deposition method was confirmed. 相似文献
147.
Huaying Ren Huan Wang Li Lin Miao Tang Shuli Zhao Bing Deng Manish Kumar Priydarshi Jincan Zhang Hailin Peng Zhongfan Liu 《Nano Research》2017,10(4):1189-1199
In the chemical vapor deposition growth of large-area graphene polycrystalline thin films,the coalescence of randomly oriented graphene domains results in a high density of uncertain grain boundaries (GBs).The structures and properties of various GBs are highly dependent on the misorientation angles between the graphene domains,which can significantly affect the performance of the graphene films and impede their industrial applications.Graphene bicrystals with a specific type of GB can be synthesized via the controllable growth of graphene domains with a predefined lattice orientation.Although the bicrystal has been widely investigated for traditional bulk materials,no successful synthesis strategy has been presented for growing two-dimensional graphene bicrystals.In this study, we demonstrate a simple approach for growing well-aligned large-domain graphene bicrystals with a confined tilt angle of 30° on a facilely recrystallized single-crystal Cu (100) substrate.Control of the density of the GBs with a misorientation angle of 30° was realized via the controllable rapid growth of subcentimeter graphene domains with the assistance of a cooperative catalytic surface-passivation treatment.The large-area production of graphene bicrystals consisting of the sole specific GBs with a tunable density provides a new material platform for fundamental studies and practical applications. 相似文献
148.
149.
The present paper considers the microstructures of Al–Mg/oxide ceramic interpenetrating composites made by a pressureless infiltration technique. The composites were produced using an Al–10 wt.% Mg alloy with two oxide ceramic foams, spinel (MgAl2O4) and mullite (Al6Si2O13), at 915 °C in a flowing N2 atmosphere. Full infiltration of the aluminium alloy into the ceramic preform has been achieved with good bonding between the metal and ceramic phases. The composites were characterised by a range of techniques and compared with those for alumina from the literature. It has been found that the metal–ceramic interface of the composite consisted of an oxide layer near the ceramic phase and a nitride layer from Mg3N2 to AlN near the metal phase. The improvement of Al wetting and adhesion on the oxide ceramics by the addition of Mg and in the presence of N2 was studied by a sessile drop technique to clarify which compound that formed at the interface contributed to the spontaneous infiltration. 相似文献
150.