超细钼粉的活化还原制备方法

本文在低温下经一次纯氢还原后由添加加某些氯化铵的仲钼酸铵制备超细钼粉的可调变量及其应用。用此方法制备的钼粉，其ＢＥＴ平均粒度为０．１微米且粉末具有良好烧结性能。论述了还原机理，估计还原过程的反应激活能（量）为６５．２ＫＪ／ｍｏｌ。     

铜钼叠层基板的热学特性仿真研究

采用有限元方法,仿真研究了不同层数和材料厚度比的铜钼叠层基板对芯片散热特性的影响。结果表明,2层和3层的铜钼叠层材料均可以有效综合Cu高热导率和Mo低膨胀系数的优点。在相同铜钼总厚度比的情况下,相比于2层材料,3层材料可以实现更好的散热特性。对于1 mm的基板厚度,铜钼铜厚度比为0.2∶0.6∶0.2时可以同时实现较低的温度和热应力。通过调整基板结构参数,可以显著改变芯片的最高温度和最大热应力,满足不同封装领域的需求。     

MoO3/Mo混合预压制粒制备粗钼粉

介绍一种粗钼粉的制备方式。在钼粉中加入一定比例的氧化钼粉和水,经预压制粒、氢气保护气氛下还原烧结、分级处理,制备出粗钼粉。     

纳米Fe粉的制备研究

总结了纳米Fe粉的制备方法,重点介绍了一种新的制备方法——封闭循环氢还原法。该方法以FeSO·47H2O和NaOH为原料,采用沉淀方法制备粒径为30～70nm的Fe2O3粉末,其反应条件为:反应温度50℃,反应终点pH值大于12,陈化时间1h。用封闭循环氢还原法,在400℃下还原Fe2O3得到了Fe粉。其粒径在20～50nm之间,含量为99.16%。     

微复合技术制备超细CaSiO_3导电粉

用sol-gel法粉体技术和化学镀膜技术的微观复合,在溶液中得到超细CaSiO3导电粉。讨论了醛基溶液浓度、溶液pH值对导电粉性能的影响,确定了导电粉制备的工艺条件为:n(CaSiO3粉体)∶n(Tollen试剂)=1∶1,且pH=9。用SEM/EDS对粉体形貌和元素组成进行表征和分析,得出CaSiO3导电粉体粒径为30~50μm,体积电阻率在10–6?·m以下。     

SiC/Cu-Al复合材料无压浸渍制备工艺的研究

利用化学镀法在SiC颗粒表面包覆Cu层制备了SiC/Cu复合粉体,然后将其压制成预制体并在熔融铝液中无压浸渍,制出了SiC/Cu-Al复合材料.研究了浸渍温度和时间对所制SiC/Cu-Al复合材料浸渍效果的影响.结果表明:SiC颗粒表面的Cu包覆层分布均匀;在800℃、保温2h条件下制备的SiC/Cu-Al复合材料显微...     

Cocatalyst Engineering with Robust Tunable Carbon-Encapsulated Mo-Rich Mo/Mo2C Heterostructure Nanoparticle for Efficient Photocatalytic Hydrogen Evolution

Cocatalyst engineering with non-noble metal nanomaterials can play a vital role in low-cost, sustainable, and large-scale photocatalytic hydrogen production. This research adopts slow carburization and simultaneous hydrocarbon reduction to synthesize carbon-encapsulated Mo/Mo₂C heterostructure nanoparticles, namely Mo/Mo₂C@C cocatalyst. Experimental and theoretical investigations indicate that the Mo/Mo₂C@C cocatalysts have a nearly ideal hydrogen-adsorption free energy (ΔG_H*), which results in the accelerated HER kinetics. As such, the cocatalysts are immobilized onto organic polymer semiconductor g-C₃N₄ and inorganic semiconductor CdS, resulting in Mo/Mo₂C@C/g-C₃N₄ and Mo/Mo₂C@C/CdS catalysts, respectively. In photocatalytic hydrogen evolution application under visible light, the Mo/Mo₂C@C with g-C₃N₄ and CdS can form the Schottky junctions via appropriate band alignment, greatly suppressing the recombination of photoinduced electron-hole pairs. The surface carbon layer as the conducting scaffolds and Mo metal facilitates electron transfer and electron-hole separation, favoring structural stability and offering more reaction sites and interfaces as electron mediators. As a result, these catalysts exhibit high H₂ production rates of 2.7 mmol h⁻¹ g⁻¹ in basic solution and 98.2 mmol h⁻¹ g⁻¹ in acidic solution, respectively, which is significantly higher than that of the bench-mark Pt-containing catalyst. The proposed cocatalyst engineering approach is promising in developing efficient non-noble metal cocatalysts for rapid hydrogen production.     

Cu/Mo共掺K_(0.5)Bi_(0.5)TiO_3陶瓷材料的PTC特性

采用以聚乙烯醇为聚合剂的湿化学方法合成制备了K0.5Bi0.5(Ti1–2xCuxMox)O3(x=0.01,0.06)陶瓷材料。利用X射线衍射、扫描电子显微镜、电阻–温度测试和交流阻抗谱分析对材料的微观组织和热敏特性进行了表征。结果表明:Cu/Mo共掺的K0.5Bi0.5TiO3陶瓷具有钙钛矿结构,并呈现明显的PTC效应;K0.5Bi0.5(Ti0.88Cu0.06Mo0.06)O3陶瓷的居里点为155℃,室温电阻为1 454,升阻比为2.62个数量级。材料的PTC效应主要来源于晶界电阻效应,遵循Heywang模型。     

Mo/Al/Mo结构电极的坡度角和关键尺寸差研究

Mo/Al/Mo结构金属作为TFT的电极,刻蚀后的坡度角和关键尺寸差是重要的参数。明确影响坡度角和关键尺寸差的工艺参数,进而控制坡度角和关键尺寸差,这对工艺制程至关重要。本文探究了膜层结构、曝光工艺、刻蚀工艺对坡度角和关键尺寸差的影响,并对刻蚀工艺进行正交试验设计。实验结果表明:Al膜厚每减小60nm,坡度角下降约9°,关键尺寸差增加0.1μm。曝光工艺中,显影后烘烤会增加光阻粘附力,导致关键尺寸差减小0.1μm,同时坡度角增加约9°。刻蚀工艺中,过刻量每增加10%,坡度角下降3.3°,关键尺寸差增加0.14μm;正交试验结果表明,对关键尺寸差、刻蚀均一性、坡度角影响因素的重要性顺序是:液刀流量Air Plasma电压水刀流量。经上述探究表明,坡度角和关键尺寸差呈负相关关系,刻蚀程度增加,关键尺寸差增加,而坡度角则减小。可以通过调节工艺参数对坡度角和关键尺寸差进行控制。     

氢等离子体还原制备纳米镍粉/铜粉研究

通过氢等离子体一步还原碱式碳酸盐制备了纳米金属镍粉和铜粉,并利用X射线衍射仪(XRD)、场发射扫描电子显微镜( FESEM)检测了产物的纯度、晶体结构、颗粒尺寸和形貌.分析了氢等离子体还原合成金属粉体的过程.结果表明:产物为纯相的金属镍粉和部分氧化的铜粉,粒度均匀、分散性好,平均粒径约为100 nm.氢等离子体还原过程...     

The effect of Mo back contact ageing on Cu(In,Ga)Se2 thin‐film solar cells

In this work, we investigate the effect of ageing Mo‐coated substrates in a dry and N₂ flooded cabinet. The influence was studied by preparing Cu(In,Ga)Se₂ solar cells and by comparing the electrical performance with devices where the Mo layer was not aged. The measurements used for this study were current–voltage (J‐V), external quantum efficiency (EQE), secondary ion mass spectroscopy (SIMS) and capacitance–voltage (C‐V). It was concluded that devices prepared with the aged Mo layer have, in average, an increase of 0.8% in efficiency compared with devices that had a fresh Mo layer. Devices with aged Mo exhibited a nominal increase of 12.5 mV of open circuit voltage, a decrease of 1.1 mA/cm⁻² of short circuit current and a fill factor increase of 2.4%. Heat treatment of fresh Mo layers in oxygen atmosphere was also studied as an alternative to ageing and was shown to provide a similar effect to the aged device's performance. Copyright © 2013 John Wiley & Sons, Ltd.     

用Al或Mo/Al/Mo低阻材料改善4-Mask工艺中Al腐蚀的方法

为了减少制造工艺的过程,改进的4-Mask工艺中采用Al基的数据线已得到进一步的完善。但这个工艺仍存在很多问题,主要是为减少工艺过程,而引入干法刻蚀对Al有腐蚀作用。本文应用CF4/O2等离子体处理,很好地阻止了对Al的腐蚀,得到很好的效果,对改进后4-Mask工艺的进一步应用具有非常重要的意义。     

Controlled growth of Mo2C pyramids on liquid Cu surface

Precise spatial control of 2D materials is the key capability of engineering their optical, electronic, and mechanical properties. However, growth of novel 2D Mo₂C on Cu surface by chemical vapor deposition method was revealed to be seed-induced 2D growth, limiting further synthesis of complex Mo₂C spatial structures. In this research, we demonstrate the controlled growth of Mo₂C pyramids with numerous morphologies, which are characterized with clear terraces within the structures. The whole evolution for Mo₂C pyramids in the coursed of CVD process has been detected, posing significant potential in probing growth mechanism. The formation of the Mo₂C pyramids arises from the supersaturation-induced nucleation and concentration-gradient driven diffused growth of a new Mo₂C layer on the edged areas of intrinsic ones, as supported by STEM imaging. This work provides a novel Mo₂C-based pyramid structure and further reveals a sliding growth mechanism, which could offer impetus for the design of new 3D spatial structures of Mo₂C and other 2D materials.     

Optical response of planar Mo/n-Si/Mo structures with long neutral region and Schottky barriers at both ends

Influence of neutral region on the low frequency (100 Hz to 1 MHz) optical signal response of planar molybdenum/n-type silicon/molybdenum structures with Schottky barriers at both ends has been investigated. It is found that the presence of the neutral region under optical illumination can enhance the device signal current and the spectrum of increment in the signal current exhibits a low turn-over frequency due to its diffusion mechanism. An equivalent circuit representation of such a structure has also been proposed.