这项工作是由维克森林化学系和维克森林中心能源，环境和可持续发展（CEES）的支持。我们感谢查尔斯·穆尼和北卡罗莱纳州立大学与SEM拍摄辅助的分析仪器设备。

1.准备干凝胶颗粒<ol><li>凝胶合成<ol><li>添加25毫米磁力搅拌棒和113毫升去离子水至500mL烧杯中。磁搅拌在不形成旋涡率最高的去离子水。 </li><li>慢慢无水氯化锆13.05克（0.056摩尔）以小的增量添加到去离子水中。所有的无水氯化锆溶解后，添加葡萄糖的53.29克（0.296摩尔）至溶液中。 </li><li>在所有葡萄糖的已溶解在该溶液中，添加硝酸钇六水合物3.73克（0.01摩尔）至溶液中。增加磁力搅拌的至〜700转的速率和等待所有的硝酸钇六水合物的溶液中溶解。 </li><li>添加42毫升的环氧丙烷到该溶液中。继续在700〜转速下搅拌该环氧丙烷与水溶液混合。一旦环氧丙烷与水溶液（〜10秒）混合，降低磁性搅拌吨O〜150转。 </li><li>继续搅拌，直到磁性搅拌棒停止移动由于形成凝胶的。该凝胶通常形成在3分钟内。 注意:添加无水氯化锆到去离子水中是高度放热的反应，并且如果它被添加太快无水氯化锆将羽。 在第1.1节中提供的制剂中。对应于葡萄糖，以总金属（锆+钇）的4.5摩尔比1。代表结果部分包括用于血糖为0总金属摩尔比数据:1，2.25:1和4.5:1。葡萄糖在制剂中的量仅由葡萄糖溶液中的溶解度的限制。作为参考，在葡萄糖的水在20℃下的最大溶解度是47.8重量％。 15 </li></ol></li><li>老龄化和洗涤凝胶<ol><li>紧密覆盖包含用Parafilm凝胶中的烧杯中，并让它年龄24个小时通过使该被覆盖的烧杯中于室温下。 </li><li>从烧杯中取出盖，倒出在凝胶顶部的液体。 </li><li>添加300毫升的无水乙醇中，以含有凝胶的烧杯中，盖紧用Parafilm烧杯中，并留下在室温下将烧杯覆盖24小时。 </li><li>重复步骤1.2.3总共三个乙醇洗涤过的72小时的总时间两次。 </li></ol></li><li>将凝胶干燥成干凝胶<ol><li>从烧杯中取出凝胶，并使用实验室刮刀将其放置在2L瓷蒸发皿（顶部外径24厘米）。 </li><li>破凝胶成约1cm×1cm的片用抹刀和摊开片蒸发皿的表面上。 </li><li>让在环境条件下的凝胶块干燥一周或直至凝胶干燥。该凝胶被认为是干的时候才可以被研磨成细粉。 </li><li>研磨所有的干凝胶与一个研钵细粉。 注意:一旦凝胶是干的，它是认为是一种干凝胶，因为它在环境条件下干燥。 </li></ol></li><li>按干凝胶制成颗粒<ol><li>放置1克干凝胶粉末的成直径为13mm的圆筒状压丸机模头。 </li><li>使用液压机，应用22千牛力为90秒至干凝胶凝胶压成丸粒。 </li><li>慢慢松开新闻界施加的力。慢慢地退出了颗粒沉淀模具，然后小心地取出小球。 </li></ol></li></ol> 2.烧结干凝胶颗粒在惰性气氛中<ol><li>放置干凝胶沉淀在氧化铝或氧化钇稳定的氧化锆板和板装入管式炉的中心。 </li><li>在三分之一每分钟工作管的容积的速率流动的氩气。这对应于750毫升的氩气流量·分钟-1在这项工作中使用的工作管。放空气体出口到通风橱。 </li><li>流动氩气的至少15分钟bEFORE开始以加热管式炉中。 </li><li>同时以恒定速率，程序管式炉的温度控制器，以下列加热程序连续流动的氩气: <ol><li>保持在室温下15分钟。 </li><li>热至850℃以5℃的升温速率·分钟-1。 </li><li>热到所需的烧结温度在2℃·分钟-1的升温速率。 </li><li>保持在所期望的烧结温度下2小时。 </li><li>冷却至850℃，以2℃的升温速率·分钟-1。 </li><li>冷却至室温，在5℃分钟-1的升温速率。 </li></ol></li><li>启动该程序并仔细检查的是，管式炉被加热以下在2.3节中所提供的时间表。 </li><li>从管式炉中除去颗粒中的加热程序完成后。 </li></ol> 3.确定碳模板浓度<ol><li>切〜50毫克片出来的烧结干凝胶粒料使用工具刀和研磨成用玛瑙研钵和研杵细粉。 </li><li>地方〜50毫克细粉末放进氧化铝样品杯为热重量分析。 </li><li>使用热重分析仪（TGA），加热样品以10℃的速率·分钟-1从环境温度到1200℃，同时在100毫升的速率流过样品空气·分钟-1。 </li><li>计算在重量发生之间〜350℃和〜700℃的变化百分比。此重量百分比对应于样品中的总碳含量。 注:如果在350℃〜700℃范围内发生的重量增加，碳化物相已形成和碳含量的计算比较复杂。对于这种情况，请参考文献中描述的计算。 14个碳元素分析已被用来确认碳含量可以从TGA测量来计算。 </li></ol> 4.准备高比表面积YSZ脚手架由碳去除模板<ol><li>放置烧结干凝胶沉淀在氧化铝坩埚。 </li><li>放置在坩埚到箱式炉中在700℃下2小时。 </li><li>小心地从箱式炉用不锈钢坩埚钳的热坩埚，并允许它除去多孔，白色YSZ支架之前冷却至室温一小时。 </li></ol>

<ol>
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S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=La-doped+SrTiO3+as+anode+material+for+IT-SOFC.">La-doped SrTiO3 as anode material for IT-SOFC.</a> Solid State Ionics. 192 (1), 491-493 (2011).</li><li>Choi, S., Shin, J., Kim, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+electrochemical+and+thermodynamic+characterization+of+PrBaCo2-xFexO5+&#948;+(x=0,0.5,1)+infiltrated+into+yttria-stabilized+zirconia+scaffold+as+cathodes+for+solid+oxide+fuel+cells.">The electrochemical and thermodynamic characterization of PrBaCo2-xFexO5+&#948; (x=0,0.5,1) infiltrated into yttria-stabilized zirconia scaffold as cathodes for solid oxide fuel cells.</a> J. Power Sources. 201, 10-17 (2012).</li><li>Kungas, R., Kim, J. S., Vohs, J. M., Gorte, R. 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我们什么都没有透露。

与此原位碳模板化方法，可以创建并在传统的陶瓷支架的烧结温度保持在混合金属氧化物nanomorphology。所得到的表面区域比传统烧结支架更高高达80倍且至多比复合物沉积技术制造的支架高4倍。 14氧化丙烯葡萄糖凝胶系统是用于调谐碳模板的浓度，允许一个系统地控制10体积％的碳和几乎100体积％之间的碳碳模板浓度非常灵活。 还有的程序三个关键步?...

的固体氧化物燃料电池（SOFC）很有希望作为一种替代能源转换技术为高效地生成清洁的电能。 1取得了重大进展在研究这项技术的发展作出的;然而，在电极性能的改进仍然需要实现可靠的商业化。电极通常包括与装饰支架表面上的电催化颗粒的多孔陶瓷支架。甲大量的研究集中在提高电催化颗粒的表面积以提高性能，2，3，4，5，6，7，8，但有上增加支架的表面积非常小的研究。增加支架表面因为它们在高温下烧结，1100℃至1500℃区域是具有挑战性的。 通过传统的烧结处理的支架通常具有0.1-1米2·克-1的比表面积。 8，9，10，11上有增加支架表面积的报道很少。在一种情况下，传统上烧结支架的表面积通过溶解和支架表面的沉淀用氢氟酸增强，实现了2米2·克-1的比表面积。 12在另一个，通过使用脉冲激光沉积完全避免高温，实现为20m 2·克-1的比表面积。 13我们的技术的发展背后的原理是建立一个低成本的制造的过程，提供了前所未有的支架表面区域，并使用传统的烧结温度，使得该方法可以很容易地通过。与技术报告这里，支架的表面积高达80米2·克-1已被证实，而在传统的烧结温度下被处理。 14 我们的研究主要是由SOFC电极工程的动机，但技术更广泛地应用于其他领域和应用。一般来说， 原位碳模板的方法是，可以产生纳米结构的，高表面积的混合金属陶瓷材料粉末或多孔支架形式的灵活的方法。正是在这种混合金属陶瓷组合物，表面积，孔隙度和孔径大小都可以被系统地调谐灵活。高的温度通常需要以形成混合金属陶瓷所希望的相，并且该方法保留陶瓷nanomorphology瓦特往往微不足道，允许一个基本上选择任意的加工温度。 该方法涉及一个杂化无机 - 有机 - 丙烯基氧化物凝胶的合成，与金属离子的阱限定化学计量和无机的比率有机物含量。将凝胶在环境条件下干燥，以形成干凝胶。干凝胶在氩气氛中，在所期望的温度下烧结。在加热时，有机成分分解留下原位碳模板，这仍然是用于烧结的持续时间。碳模板随后通过低温氧化除去在空气中，导致纳米结构化，高表面积陶瓷。

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Zirconium (IV) chloride, 99.5+%</td>
			<td>Alfa Aesar</td>
			<td>12104</td>
			<td>Air sensitive</td>
		</tr>
		<tr>
			<td>Yttium (III) nitrate hexadydrate, 99.9%</td>
			<td>Alfa Aesar</td>
			<td>12898</td>
			<td>Oxidizer</td>
		</tr>
		<tr>
			<td>D+ Glucose Anhydrous, &#8805; 99.5%</td>
			<td>US Biological Life Sciences</td>
			<td>G3050</td>
			<td></td>
		</tr>
		<tr>
			<td>(&#177;)-Propylene Oxide, &#8805; 99%</td>
			<td>Sigma Aldrich</td>
			<td>110205</td>
			<td>Extremely flammable</td>
		</tr>
		<tr>
			<td>Ethanol 200 Proof</td>
			<td>Decon Laboratories, Inc.</td>
			<td>2716GEA</td>
			<td></td>
		</tr>
		<tr>
			<td>Argon, (99.997%)</td>
			<td>Airgas</td>
			<td>AR 300</td>
			<td>Industrial grade</td>
		</tr>
	</tbody>
</table>

high temperature fabrication of nanostructured yttria-stabilized-zirconia (ysz) scaffolds by in situ carbon templating xerogels

我们证明为多孔的，纳米结构的氧化钇稳定的氧化锆的高温制造（YSZ，8摩尔％的氧化钇- 92摩尔％的氧化锆）的方法，具有可调谐的比表面积的支架高达80米2·克-1。锆盐，钇盐和葡萄糖的水溶液是与环氧丙烷（PO）混合以形成凝胶。将凝胶在环境条件下干燥，以形成干凝胶。干凝胶压成丸粒，然后在氩气气氛中烧结。在烧结过程中，一个YSZ陶瓷相形式和有机成分分解，留下无定形碳。 原位形成碳用作硬模板，在烧结温度下保持高的表面积YSZ nanomorphology。碳随后通过氧化除去在空气中在低温下，从而产生多孔的，纳米结构的YSZ的支架。碳模板和最终支架表面积的浓度可以是系统性通过在凝胶合成改变葡萄糖浓度LY调谐。使用中，表面积和孔径分布是由物理吸附测量来确定热重量分析（TGA）中的碳模板浓度进行定量，并使用扫描电子显微镜（SEM）的形貌进行了表征。相纯度和微晶尺寸使用X射线衍射（XRD）测定。这种制造方法提供了一种新颖的，用于实现前所未有的支架表面积和nanomorphologies用于基于陶瓷的电化学能量转换应用灵活的平台， 例如固体氧化物燃料电池（SOFC）的电极。

相纯度通过如先前通过科塔姆等报道的X射线衍射（XRD）确认。作为碳模板浓度的函数14 YSZ支架比表面积示于图1。浓度被示出为在烧结干凝胶粒料总固体的体积百分数。碳模板浓度有系统地与凝胶制剂增加的葡萄糖浓度增加而增加。金属的摩尔比从0:1至4.5: 如图1所示，比表面积系统通过增加葡萄糖为10米2·克...

Watch this Scientific Journal Video about High Temperature Fabrication of Nanostructured Yttria-Stabilized-Zirconia YSZ Scaffolds by In Situ Carbon Templating Xerogels at JoVE.com

High Temperature Fabrication of Nanostructured Yttria-Stabilized-Zirconia YSZ Scaffolds by In Situ Carbon Templating Xerogels

一种用于在1000℃和1400℃之间的温度的制造多孔纳米结构的氧化钇稳定的氧化锆（YSZ）的支架协议被呈现。

通过纳米氧化钇稳定的二氧化锆（YSZ）的支架的高温加工<em&gt;原位</em&gt;碳模板干凝胶

We demonstrate a method for the high temperature fabrication of porous, nanostructured yttria-stabilized-zirconia (YSZ, 8 mol% yttria - 92 mol% zirconia) ...

high-temperature-fabrication-nanostructured-yttria-stabilized

Research

JoVE Journal

Engineering

High Temperature Fabrication of Nanostructured Yttria-Stabilized-Zirconia (YSZ) Scaffolds by In Situ Carbon Templating Xerogels

10.5K 次观看.  Wake Forest University. 一种用于在1000℃和1400℃之间的温度的制造多孔纳米结构的氧化钇稳定的氧化锆（YSZ）的支架协议被呈现。 

视频: High Temperature Fabrication of Nanostructured Yttria-Stabilized-Zirconia YSZ Scaffolds by In Situ Carbon Templating Xerogels

Fabrication, Densification, and Replica Molding of 3D Carbon Nanotube Microstructures

The introduction of new materials and processes to microfabrication has, in large part, enabled many important advances in microsystems, lab-on-a-chip devices, and their applications. In particular, capabilities for cost-effective fabrication of polymer microstructures were transformed by the advent of soft lithography and other micromolding techniques 1, 2, and this led a revolution in applications of microfabrication to biomedical engineering and biology. Nevertheless, it remains challenging to fabricate microstructures with well-defined nanoscale surface textures, and to fabricate arbitrary 3D shapes at the micro-scale. Robustness of master molds and maintenance of shape integrity is especially important to achieve high fidelity replication of complex structures and preserving their nanoscale surface texture. The combination of hierarchical textures, and heterogeneous shapes, is a profound challenge to existing microfabrication methods that largely rely upon top-down etching using fixed mask templates. On the other hand, the bottom-up synthesis of nanostructures such as nanotubes and nanowires can offer new capabilities to microfabrication, in particular by taking advantage of the collective self-organization of nanostructures, and local control of their growth behavior with respect to microfabricated patterns. 
Our goal is to introduce vertically aligned carbon nanotubes (CNTs), which we refer to as CNT "forests", as a new microfabrication material. We present details of a suite of related methods recently developed by our group: fabrication of CNT forest microstructures by thermal CVD from lithographically patterned catalyst thin films; self-directed elastocapillary densification of CNT microstructures; and replica molding of polymer microstructures using CNT composite master molds. In particular, our work shows that self-directed capillary densification ("capillary forming"), which is performed by condensation of a solvent onto the substrate with CNT microstructures, significantly increases the packing density of CNTs. This process enables directed transformation of vertical CNT microstructures into straight, inclined, and twisted shapes, which have robust mechanical properties exceeding those of typical microfabrication polymers. This in turn enables formation of nanocomposite CNT master molds by capillary-driven infiltration of polymers. The replica structures exhibit the anisotropic nanoscale texture of the aligned CNTs, and can have walls with sub-micron thickness and aspect ratios exceeding 50:1. Integration of CNT microstructures in fabrication offers further opportunity to exploit the electrical and thermal properties of CNTs, and diverse capabilities for chemical and biochemical functionalization 3.

We present methods for fabrication of patterned microstructures of vertically aligned carbon nanotubes (CNTs), and their use as master molds for production of polymer microstructures with organized nanoscale surface texture. The CNT forests are densified by condensation of solvent onto the substrate, which significantly increases their packing density and enables self-directed formation of 3D shapes.

制备，致密，副本三维碳纳米管微结构成型

The introduction of new materials and processes to microfabrication has, in large part, enabled many important advances in microsystems, lab-on-a-chip ...

科研

工程学

Fabrication of Silica Ultra High Quality Factor Microresonators

Whispering gallery resonant cavities confine light in circular orbits at their periphery.1-2 The photon storage lifetime in the cavity, quantified by the quality factor (Q) of the cavity, can be in excess of 500ns for cavities with Q factors above 100 million. As a result of their low material losses, silica microcavities have demonstrated some of the longest photon lifetimes to date1-2. Since a portion of the circulating light extends outside the resonator, these devices can also be used to probe the surroundings. This interaction has enabled numerous experiments in biology, such as single molecule biodetection and antibody-antigen kinetics, as well as discoveries in other fields, such as development of ultra-low-threshold microlasers, characterization of thin films, and cavity quantum electrodynamics studies.3-7
The two primary silica resonant cavity geometries are the microsphere and the microtoroid. Both devices rely on a carbon dioxide laser reflow step to achieve their ultra-high-Q factors (Q&gt;100 million).1-2,8-9 However, there are several notable differences between the two structures. Silica microspheres are free-standing, supported by a single optical fiber, whereas silica microtoroids can be fabricated on a silicon wafer in large arrays using a combination of lithography and etching steps. These differences influence which device is optimal for a given experiment.
Here, we present detailed fabrication protocols for both types of resonant cavities. While the fabrication of microsphere resonant cavities is fairly straightforward, the fabrication of microtoroid resonant cavities requires additional specialized equipment and facilities (cleanroom). Therefore, this additional requirement may also influence which device is selected for a given experiment.
Introduction
An optical resonator efficiently confines light at specific wavelengths, known as the resonant wavelengths of the device. 1-2 The common figure of merit for these optical resonators is the quality factor or Q. This term describes the photon lifetime (&tau;o) within the resonator, which is directly related to the resonator's optical losses. Therefore, an optical resonator with a high Q factor has low optical losses, long photon lifetimes, and very low photon decay rates (1/&tau;o). As a result of the long photon lifetimes, it is possible to build-up extremely large circulating optical field intensities in these devices. This very unique property has allowed these devices to be used as laser sources and integrated biosensors.10
A unique sub-class of resonators is the whispering gallery mode optical microcavity. In these devices, the light is confined in circular orbits at the periphery. Therefore, the field is not completely confined within the device, but evanesces into the environment. Whispering gallery mode optical cavities have demonstrated some of the highest quality factors of any optical resonant cavity to date.9,11 Therefore, these devices are used throughout science and engineering, including in fundamental physics studies and in telecommunications as well as in biodetection experiments. 3-7,12
Optical microcavities can be fabricated from a wide range of materials and in a wide variety of geometries. A few examples include silica and silicon microtoroids, silicon, silicon nitride, and silica microdisks, micropillars, and silica and polymer microrings.13-17 The range in quality factor (Q) varies as dramatically as the geometry. Although both geometry and high Q are important considerations in any field, in many applications, there is far greater leverage in boosting device performance through Q enhancement. Among the numerous options detailed previously, the silica microsphere and the silica microtoroid resonator have achieved some of the highest Q factors to date.1,9 Additionally, as a result of the extremely low optical loss of silica from the visible through the near-IR, both microspheres and microtoroids are able to maintain their Q factors over a wide range of testing wavelengths.18 Finally, because silica is inherently biocompatible, it is routinely used in biodetection experiments.
In addition to high material absorption, there are several other potential loss mechanisms, including surface roughness, radiation loss, and contamination loss.2 Through an optimization of the device size, it is possible to eliminate radiation losses, which arise from poor optical field confinement within the device. Similarly, by storing a device in an appropriately clean environment, contamination of the surface can be minimized. Therefore, in addition to material loss, surface scattering is the primary loss mechanism of concern.2,8
In silica devices, surface scattering is minimized by using a laser reflow technique, which melts the silica through surface tension induced reflow. While spherical optical resonators have been studied for many years, it is only with recent advances in fabrication technologies that researchers been able to fabricate high quality silica optical toroidal microresonators (Q&gt;100 million) on a silicon substrate, thus paving the way for integration with microfluidics.1
The present series of protocols details how to fabricate both silica microsphere and microtoroid resonant cavities. While silica microsphere resonant cavities are well-established, microtoroid resonant cavities were only recently invented.1 As many of the fundamental methods used to fabricate the microsphere are also used in the more complex microtoroid fabrication procedure, by including both in a single protocol it will enable researchers to more easily trouble-shoot their experiments.

We describe the use of a carbon dioxide laser reflow technique to fabricate silica resonant cavities, including free-standing microspheres and on-chip microtoroids. The reflow method removes surface imperfections, allowing long photon lifetimes within both devices. The resulting devices have ultra high quality factors, enabling applications ranging from telecommunications to biodetection.

硅胶超高品质因子微谐振器的制造

Whispering gallery resonant cavities confine light in circular orbits at their periphery.1-2 The photon storage lifetime in the cavity, quantified by the ...

Preparation and Reactivity of Gasless Nanostructured Energetic Materials

High-Energy Ball Milling (HEBM) is a ball milling process where a powder mixture placed in the ball mill is subjected to high-energy collisions from the balls. Among other applications, it is a versatile technique that allows for effective preparation of gasless reactive nanostructured materials with high energy density per volume (Ni+Al, Ta+C, Ti+C). The structural transformations of reactive media, which take place during HEBM, define the reaction mechanism in the produced energetic&#160;composites. Varying the processing conditions permits fine tuning of the milling-induced microstructures of the fabricated composite particles. In turn, the reactivity, i.e., self-ignition temperature, ignition delay time, as well as reaction kinetics, of high energy density materials depends on its microstructure. Analysis of the milling-induced microstructures suggests that the formation of fresh oxygen-free intimate high surface area contacts between the reagents is responsible for the enhancement of their reactivity. This manifests itself in a reduction of ignition temperature and delay time, an increased rate of chemical reaction, and an overall decrease of the effective activation energy of the reaction. The protocol provides a detailed description for the preparation of reactive nanocomposites with tailored microstructure using short-term HEBM method. It also describes a high-speed thermal imaging technique to determine the ignition/combustion characteristics of the energetic materials. The protocol can be adapted to preparation and characterization of a variety of nanostructured energetic composites.

This protocol describes the preparation of gasless nanostructured energetic materials (Ni+Al, Ta+C, Ti+C) using the short-term high-energy ball milling (HEBM) technique. It also describes a high-speed thermal imaging method to study the reactivity of mechanically fabricated nanocomposites. These protocols can be extended to other reactive nanostructured energetic materials.

准备和无气腹纳米结构的反应含能材料

High-Energy Ball Milling (HEBM) is a ball milling process where a powder mixture placed in the ball mill is subjected to high-energy collisions from the ...

Fabrication of Low Temperature Carbon Nanotube Vertical Interconnects Compatible with Semiconductor Technology

We demonstrate a method for the low temperature growth (350 &#176;C) of vertically-aligned carbon nanotubes (CNT) bundles on electrically conductive thin-films. Due to the low growth temperature, the process allows integration with modern low-&#954; dielectrics and some flexible substrates. The process is compatible with standard semiconductor fabrication, and a method for the fabrication of electrical 4-point probe test structures for vertical interconnect test structures is presented. Using scanning electron microscopy the morphology of the CNT bundles is investigated, which demonstrates vertical alignment of the CNT and can be used to tune the CNT growth time. With Raman spectroscopy the crystallinity of the CNT is investigated. It was found that the CNT have many defects, due to the low growth temperature. The electrical current-voltage measurements of the test vertical interconnects displays a linear response, indicating good ohmic contact was achieved between the CNT bundle and the top and bottom metal electrodes. The obtained resistivities of the CNT bundle are among the average values in the literature, while a record-low CNT growth temperature was used.

A method for the growth of low temperature vertically-aligned carbon nanotubes, and the subsequent fabrication of vertical interconnect electrical test structures using semiconductor fabrication is presented.

低温碳纳米管垂直互连的制作兼容半导体技术

We demonstrate a method for the low temperature growth (350 &#176;C) of vertically-aligned carbon nanotubes (CNT) bundles on electrically conductive ...

Printing Fabrication of Bulk Heterojunction Solar Cells and In Situ Morphology Characterization

Polymer-based materials hold promise as low-cost, flexible efficient photovoltaic devices. Most laboratory efforts to achieve high performance devices have used devices prepared by spin coating, a process that is not amenable to large-scale fabrication. This mismatch in device fabrication makes it difficult to translate quantitative results obtained in the laboratory to the commercial level, making optimization difficult. Using a mini-slot die coater, this mismatch can be resolved by translating the commercial process to the laboratory and characterizing the structure formation in the active layer of the device in real time and in situ as films are coated onto a substrate. The evolution of the morphology was characterized under different conditions, allowing us to propose a mechanism by which the structures form and grow. This mini-slot die coater offers a simple, convenient, material efficient route by which the morphology in the active layer can be optimized under industrially relevant conditions. The goal of this protocol is to show experimental details of how a solar cell device is fabricated using a mini-slot die coater and technical details of running in situ structure characterization using the mini-slot die coater.

Printing Fabrication of Bulk Heterojunction Solar Cells and In Situ Morphology Characterization

Here, we present a protocol to fabricate organic thin film solar cells using a mini-slot die coater and related in-line structure characterizations using synchrotron scattering techniques.

散装异质结太阳能电池的印刷和制作<em&gt;原位</em&gt;形态特征

Polymer-based materials hold promise as low-cost, flexible efficient photovoltaic devices. Most laboratory efforts to achieve high performance devices ...

Fabrication of 3D Carbon Microelectromechanical Systems (C-MEMS)

A wide range of carbon sources are available in nature, with a variety of micro-/nanostructure configurations. Here, a novel technique to fabricate long and hollow glassy carbon microfibers derived from human hairs is introduced. The long and hollow carbon structures were made by the pyrolysis of human hair at 900 &#176;C in a N2 atmosphere. The morphology and chemical composition of natural and pyrolyzed human hairs were investigated using scanning electron microscopy (SEM) and electron-dispersive X-ray spectroscopy (EDX), respectively, to estimate the physical and chemical changes due to pyrolysis. Raman spectroscopy was used to confirm the glassy nature of the carbon microstructures. Pyrolyzed hair carbon was introduced to modify screen-printed carbon electrodes ; the modified electrodes were then applied to the electrochemical sensing of dopamine and ascorbic acid. Sensing performance of the modified sensors was improved as compared to the unmodified sensors. To obtain the desired carbon structure design, carbon micro-/nanoelectromechanical system (C-MEMS/C-NEMS) technology was developed. The most common C-MEMS/C-NEMS fabrication process consists of two steps: (i) the patterning of a carbon-rich base material, such as a photosensitive polymer, using photolithography; and (ii) carbonization through the pyrolysis of the patterned polymer in an oxygen-free environment. The C-MEMS/NEMS process has been widely used to develop microelectronic devices for various applications, including in micro-batteries, supercapacitors, glucose sensors, gas sensors, fuel cells, and triboelectric nanogenerators. Here, recent developments of a high-aspect ratio solid and hollow carbon microstructures with SU8 photoresists are discussed. The structural shrinkage during pyrolysis was investigated using confocal microscopy and SEM. Raman spectroscopy was used to confirm the crystallinity of the structure, and the atomic percentage of the elements present in the material before and after pyrolysis was measured using EDX.

Fabrication of 3D Carbon Microelectromechanical Systems C-MEMS

Long and hollow glassy carbon microfibers were fabricated based on the pyrolysis of a natural product, human hair. The two fabrication steps of carbon microelectromechanical and carbon nanoelectromechanical systems, or C-MEMS and C-NEMS, are: (i) photolithography of a carbon-rich polymer precursor and (ii) pyrolysis of the patterned polymer precursor.

3D碳微机电系统（C-MEMS）的制造

A wide range of carbon sources are available in nature, with a variety of micro-/nanostructure configurations. Here, a novel technique to fabricate long ...

Measurements of Soil Carbon by Neutron-Gamma Analysis in Static and Scanning Modes

The herein described application of the inelastic neutron scattering (INS) method for soil carbon analysis is based on the registration and analysis of gamma rays created when neutrons interact with soil elements. The main parts of the INS system are a pulsed neutron generator, NaI(Tl) gamma detectors, split electronics to separate gamma spectra due to INS and thermo-neutron capture (TNC) processes, and software for gamma spectra acquisition and data processing. This method has several advantages over other methods in that it is a non-destructive in situ method that measures the average carbon content in large soil volumes, is negligibly impacted by local sharp changes in soil carbon, and can be used in stationary or scanning modes. The result of the INS method is the carbon content from a site with a footprint of ~2.5 - 3 m2 in the stationary regime, or the average carbon content of the traversed area in the scanning regime. The measurement range of the current INS system is &#62;1.5 carbon weight % (standard deviation &#177; 0.3 w%) in the upper 10 cm soil layer for a 1 hmeasurement.

Here, we present the protocol for in situ measurement of soil carbon using the neutron-gamma technique for single point measurements (static mode) or field averages (scanning mode). We also describe system construction and elaborate data treatment procedures.

静态和扫描模式下中子伽马分析法测量土壤碳

The herein described application of the inelastic neutron scattering (INS) method for soil carbon analysis is based on the registration and analysis of ...

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses

We demonstrate the use of two nuclear-based analytical methods that can follow the modifications of microstructural arrangement of iron-based metallic glasses (MGs). Despite their amorphous nature, the identification of hyperfine interactions unveils faint structural modifications. For this purpose, we have employed two techniques that utilize nuclear resonance among nuclear levels of a stable 57Fe isotope, namely M&#246;ssbauer spectrometry and nuclear forward scattering (NFS) of synchrotron radiation. The effects of heat treatment upon (Fe2.85Co1)77Mo8Cu1B14 MG are discussed using the results of ex situ and in situ experiments, respectively. As both methods are sensitive to hyperfine interactions, information on structural arrangement as well as on magnetic microstructure is readily available. M&#246;ssbauer spectrometry performed ex situ describes how the structural arrangement and magnetic microstructure appears at room temperature after the annealing under certain conditions (temperature, time), and thus this technique inspects steady states. On the other hand, NFS data are recorded in situ during dynamically changing temperature and NFS examines transient states. The use of both techniques provides complementary information. In general, they can be applied to any suitable system in which it is important to know its steady state but also transient states.

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses

Here, we present a protocol to describe ex situ and in situ investigations of structural transformations in metallic glasses. We employed nuclear-based analytical methods which inspect hyperfine interactions. We demonstrate the applicability of M&#246;ssbauer spectrometry and nuclear forward scattering of synchrotron radiation during temperature-driven experiments.

结构转换的原位和原位研究方法: 金属玻璃结晶的实例

We demonstrate the use of two nuclear-based analytical methods that can follow the modifications of microstructural arrangement of iron-based metallic ...

Radio Frequency Magnetron Sputtering of GdBa2Cu3O7&#8722;&#948;/ La0.67Sr0.33MnO3 Quasi-bilayer Films on SrTiO3 (STO) Single-crystal Substrates

Here, we demonstrate a method of coating ferromagnetic La0.67Sr0.33MnO3 (LSMO) nanoparticles on (001) SrTiO3 (STO) single-crystal substrates by radio frequency (RF) magnetron sputtering. LSMO nanoparticles were deposited with diameters from 10 to 20 nm and heights between 20 and 50 nm. At the same time, (Gd) Ba2Cu3O7&#8722;&#948; ((Gd) BCO) films were fabricated on both undecorated and LSMO nanoparticle decorated STO substrates using RF magnetron sputtering. This report also describes the properties of GdBa2Cu3O7&#8722;&#948;/ La0.67Sr0.33MnO3 quasi-bilayer films structures (e.g., crystalline phase, morphology, chemical composition); magnetization, magneto-transport, and superconducting transport properties were also evaluated.

Radio Frequency Magnetron Sputtering of GdBa2Cu3O7ÃƒÆ’Ã‚Â¢Ãƒâ€¹Ã¢â‚¬Â 'ÃƒÆ’Ã…Â½ Â´/ La0.67Sr0.33MnO3 Quasi-bilayer Films on SrTiO3 STO Single-crystal Substrates

Here, we present a protocol to grow LSMO nanoparticles and (Gd) BCO films on (001) SrTiO3 (STO) single-crystal substrates by radio frequency (RF)-sputtering.

Gdba2cu 3 o7 的射频磁控管散射-/la0.67sr 0.67 mno 3 准双层薄膜上的 srtio 3 (sto) 单晶基板上

Here, we demonstrate a method of coating ferromagnetic La0.67Sr0.33MnO3 (LSMO) nanoparticles on (001) SrTiO3 (STO) single-crystal substrates by radio ...

Hybrid Printing for the Fabrication of Smart Sensors

A method to combine additively manufactured substrates or foils and multilayer inkjet printing for the fabrication of sensor devices is presented. First, three substrates (acrylate, ceramics, and copper) are prepared. To determine the resulting material properties of these substrates, profilometer, contact angle, scanning electron microscope (SEM), and focused ion beam (FIB) measurements are done. The achievable printing resolution and suitable drop volume for each substrate are, then, found through the drop size tests. Then, layers of insulating and conductive ink are inkjet printed alternately to fabricate the target sensor structures. After each printing step, the respective layers are individually treated by photonic curing. The parameters used for the curing of each layer are adapted depending on the printed ink, as well as on the surface properties of the respective substrate. To confirm the resulting conductivity and to determine the quality of the printed surface, four-point probe and profilometer measurements are done. Finally, a measurement set-up and results achieved by such an all-printed sensor system are shown to demonstrate the achievable quality.

Here we present a protocol for the fabrication of inkjet-printed multilayer sensor structures on additively manufactured substrates and foil.

用于智能传感器制造的混合打印

A method to combine additively manufactured substrates or foils and multilayer inkjet printing for the fabrication of sensor devices is presented. First, ...