High‐Density Sb2Te3 Nanopillars Arrays by Templated,Bottom‐Up MOCVD Growth

Sb₂Te₃ exhibits several technologically relevant properties, such as high thermoelectric efficiency, topological insulator character, and phase change memory behavior. Improved performances are observed and novel effects are predicted for this and other chalcogenide alloys when synthetized in the form of high‐aspect‐ratio nanostructures. The ability to grow chalcogenide nanowires and nanopillars (NPs) with high crystal quality in a controlled fashion, in terms of their size and position, can boost the realization of novel thermoelectric, spintronic, and memory devices. Here, it is shown that highly dense arrays of ultrascaled Sb₂Te₃ NPs can be grown by metal organic chemical vapor deposition (MOCVD) on patterned substrates. In particular, crystalline Sb₂Te₃ NPs with a diameter of 20 nm and a height of 200 nm are obtained in Au‐functionalized, anodized aluminum oxide (AAO) templates with a pore density of ≈5 × 10¹⁰ cm^?2. Also, MOCVD growth of Sb₂Te₃ can be followed either by mechanical polishing and chemical etching to produce Sb₂Te₃ NPs arrays with planar surfaces or by chemical dissolution of the AAO templates to obtain freestanding Sb₂Te₃ NPs forests. The illustrated growth method can be further scaled to smaller pore sizes and employed for other MOCVD‐grown chalcogenide alloys and patterned substrates.     

Controllable fabrication of tube-in-tubes using anodic aluminum oxide templates

We have developed a method to fabricate tube-in-tubes that are relatively long and made in all the pores of porous anodic aluminum oxide (AAO) nano-templates. Relatively a very small amount of Co was deposited in the pores of AAO templates prepared without doing a voltage drop at the end of anodization, and then etched in NaOH solution. This caused the carbon nanotubes (CNTs) to grow out from all the pores, and larger diameter carbon nanotubes were also made on the inner surface of all the pores, by forming tube-in-tubes. We were able to control the gap between the inner surface of the larger tubes and the outer surface of the smaller ones of tube-in-tubes in some range by changing the etching time in NaOH solution. Tube-in-tubes that are relatively long and controlled the gap could be used as a storage, particularly for hydrogen gas.     

转移反应热和去除铝基底实验研究

铝在阳极氧化过程中放出来的热量对阳极氧化铝(AAO)模板的制备易产生不利影响,与铝基底紧连的阻挡层产生的焦耳热是主要热源.通过将铝基底置于草酸电解液外,考察了阳极氧化电压、冷却方式等因素对AAO模板制备的影响.结果表明,阳极氧化电压和冷却方式均影响电解液温度和AAO模板孔道直径尺寸.空气冷却时,30 V电压氧化8 h,制备的模板孔道直径约为40 nm,电解液温度为31℃;水浴冷却时,40 V电压氧化8 h,制备的模板孔道直径约为80 nm,电解液温度为25℃,且制备的AAO模板表面没有纳米氧化铝纤维.采用乙醇/浓盐酸混合溶液溶解铝基底,乙醇/浓盐酸的体积比为2~3时,溶解铝基底的时间约为30 min,AAO模板不受损害.     

溶胶凝胶-模板法制备一维金纳米材料

采用HAuCl4水溶液和柠檬酸三钠水溶液制备了金溶胶,利用多孔氧化铝(AAO)为模板,采用浸泡金溶胶-凝胶的方法,制备了一维金纳米材料。利用扫描电镜、透射电镜、选区电子衍射、X射线衍射对产物进行了表征。结果表明通过控制金胶的浓度和模板的浸泡时间,可分别获得管状和线状结构的一维金纳米材料,其直径为200 nm左右,长度可达几十微米,由细小的金晶粒组成。     

三污泥法处理抗生素类制药废水

为有效解决传统AAO法中存在的硝化菌、反硝化菌及聚磷菌三种细菌在污泥龄、碳源需求及回流污泥中携带的硝酸盐影响聚磷菌厌氧释放磷这三方面的矛盾，减少大量污泥回流、降低动力消耗、充分利用池容、切实提高污水处理效率，提出“三污泥”理念，对AAO进行关键性改进，改进后的缺氧池、厌氧池、好氧池等生化反应池均自带独立的泥水自动分离的装置，形成独特的三污泥系统(即纯粹的厌氧污泥、纯粹的缺氧污泥和纯粹的好氧污泥)，各池可根据运营需要各自控制污泥浓度，使各池中的活性污泥在各自最佳的环境中生长，互不干扰、相互独立，更高效发挥生物降解作用，创新性设计“改进型AAO法+生物滤池+絮凝沉淀耦合工艺”处理抗生素类制药废水，并与传统型组合技术进行比较。结果表明，进水主要污染物化学需氧量CODcr 253?581 mg/L、氨氮29.6?58.5 mg/L、全磷10.77?23.1 mg/L、设计流量30.0 L/h条件下，改进型技术取得了很好的处理效果，其CODcr、氨氮、全磷的平均去除率分别达80.2%, 73.1%, 96.1%，比改进前分别提高了6.9%, 6.1%, 3.4%，尾水CODcr、氨氮、全磷等三项指标均达到《污水综合排放标准》(GB8978-1996)的一级标准。     

一种简单的模板法制备聚苯乙烯纳米管

为了制备具有高强度聚苯乙烯纳米管及其阵列结构，以孔径仅有200nm的阳极氧化铝为模板，采用聚合物溶液浸润模板这一简单的物理技术，成功制备了具有常规相对分子质量的聚苯乙烯纳米管及其阵列。SEM和TEM测试结果表明：聚苯乙烯质量分数分别为2．5％，5．0％和10．0％的聚合物溶液可以制得管壁厚度分别为50nm，70nm和80nm的纳米管。可知聚合物溶液浓度是影响纳米管结构的主要因素之一。计算可知：聚苯乙烯质量分数为10．0％的聚合物溶液完全充满纳米孔时，溶剂挥发后高分子链沉积在孔内壁上形成纳米管的管壁厚度约为5nm。由此推断出聚合物溶液浸润阳极氧化铝模板的过程反复多次进行，并归纳出溶液浸润模板制备聚合物纳米管的多次浸润机理。     

溶液浸润法制备PS纳米管及其形成机理的初探

首次以孔径仅有200nm的阳极氧化铝(AAO)为模板，采用聚合物溶液浸润模板的物理技术，通过不同方法成功制备了常规分子量的PS纳米管及其阵列结构。SEM和TEM测试结果表明，有效地调整和控制制备方法和工艺，可制备出不同管壁厚度的聚合物纳米管．也可制备出管壁带有多孔的纳米管，还可制备出纳米线。探索了多孔模板法制备聚合物纳米管的机理。     

纳米孔模板的透射电镜观察

该文利用透射电镜对阳极氧化法制备的纳米孔模板进行了观察。纳米孔薄膜的正面观察是把纳米孔膜从模板上取下后通孔并碎化,把微小碎片放在铜网上观察;纳米孔薄膜的侧面观察是把纳米孔薄膜在ultrotome-nova超薄切片机进行切片后进行观察。结果表明,通过该两种办法,能够清楚地观察到纳米氧化孔膜的正面、侧面及纳米孔膜底部的金属颗粒,为纳米孔膜及在纳米孔内部制备的其它纳米物体观察提供了透射电镜方法。     

FRICTION PROPERTIES OF OIL-INFILTRATED POROUS AAO FILM ON AN ALUMINUM SUBSTRATE

1. IntroductionA lum inum and its alloys are used in m any engineering applications because of their highstrength-to-w eightratio and high therm alconductivities.H ow ever,high friction coefficient,poorw earresistance and low seizure load ofalum inum allo…     

合成和表征NiFe2O4纳米线阵列

采用真空灌注结合溶胶-凝胶和氧化铝模板法,在多孔氧化铝模板中制备了平均直径为50 nm的NiFe2O4纳米线阵列.X射线衍射结果显示所制备的纳米线是纯相的NiFe2O4纳米线,透射电镜和电子衍射的结果显示已制备的纳米线是多晶的且表面光滑,场发射扫描电镜图片显示纳米线是大面积且平行有序的、纳米线的长度和所用的氧化铝模板的厚度相当.磁测量的结果显示此纳米线阵列有形状各向异性,同块状材料相比矫顽力有所增强.对纳米线的生长机理做了简单的讨论.