This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (No.2014R1A2A1A11051146). This work was also supported by National Research Foundation of Korea Grant funded by the Korean Government (NRF-2014R1A1A2058350).

1.化学气相沉积（CVD）生长单层石墨烯的注意:在此研究中使用的石墨上生长铜（Cu）箔使用热化学气相沉积（CVD）技术（图1A）。生长上是均匀的2厘米×10厘米为这个系统的区域。 <ol><li>用丙酮的温和流动，异丙醇（IPA）和蒸馏水，洗涤Cu箔（2厘米×10厘米）分别。 </li><li>放置清洗Cu箔在一个2中。石英管（图1B），然后通过使用旋转泵吹扫真空（大约1毫乇）的腔室10分钟。 </li><li>配置数字化炉的温度，并且斜升炉内995℃，同时保持所需的流速（以100sccm的氩气和50sccm的氢气）（ 图1C）。 </li><li>引入20sccm的甲烷 （CH 4）的10分钟中生长的单层石墨烯。保持80 SC氩厘米和20sccm的氢气通过的过程。 </li><li>让炉冷却至室温在5分钟内，在步骤1.4中指定的流率。用氩气再吹扫室中为100sccm。 </li></ol> 2.制备石墨烯/聚乙烯对苯二甲酸酯（PET）基板<ol><li>放置石墨烯生长Cu箔（1.5厘米×2厘米）上的载玻片，并修复由商业带（ 图2A）的边缘。 </li><li>旋涂一层聚（甲基丙烯酸甲酯）（PMMA）以500rpm，持续5秒，然后3000rpm离心30秒（Figure2B）。然后，烘烤的PMMA包覆的Cu箔基材在60℃下进行2分钟，以除去溶剂残余物。 </li><li>骰子PMMA包覆铜箔成更小的构件1厘米×1.5使用刀片。 </li><li>通过将Cu箔面朝下30分钟浸泡PMMA包覆Cu箔成镍蚀刻剂贮存器（超过500毫升）。这使得在蚀刻液浮PMMA /石墨烯层（ <stroNG&gt;图2C）。一块PMMA包覆Cu箔是足够的实验向前。 </li><li>炒到PMMA /石墨烯层上载玻片，然后浸入PMMA /石墨烯层为去离子水水库。重复两次。最后，舀PMMA /石墨烯层上的PET基板（图2D），然后烘烤衬底在105℃下进行2分钟，以除去水残余物。 </li><li>通过浸渍在温水丙酮（60℃）10分钟去除的PMMA层。 </li></ol> 3.合成氧化锌纳米棒/石墨烯/氧化锌纳米棒外延双异质结的<ol><li>开始加热用40mM六水合硝酸锌的前体溶液，40毫六亚甲基四胺（HMT），并在95℃的对流烘箱（图3A）9毫聚乙烯亚胺（PEI）在DI水中60分钟。也就是说，预热过程。 </li><li>而预热的过程中，完全覆盖在基板和旋涂用5mM乙酸锌溶液的乙醇层寻在500rpm，持续5秒的石墨烯/ PET基材上Ç乙酸，然后2000rpm下60秒钟（图3B和图3C）。然后，烘烤基板在200℃下30分钟。重复两次。层的厚度约为30纳米。 </li><li>通过将基材面朝下，在95℃（图3D）浸泡种子包覆石墨烯/ PET基材入预热的溶液中。确定加热时间所需的纳米结构， 即单异质结（T &lt;12小时， 图3E）和双异质结（T&gt; 12小时， 图3F）。 </li><li>小心喷洒乙醇在基板上并干燥它在RT 1小时。 注意:对于扫描电子显微镜（SEM），使用剃刀刀片切块的样品为更小的片5毫米×5毫米，安装在SEM阶段样品。 </li></ol> 4.制造压电纳米发电机的注:压电NANOGenerator在这项研究中具有三个电极（顶部，中部，底部）。使用铟锡氧化物（ITO）涂覆的PET作为底电极（图4A）。 <ol><li>旋涂的层的聚二甲基硅氧烷（PDMS）在500rpm下5秒，然后6,000rpm下60秒，以形成ITO和ZnO纳米棒（图4B）之间的绝缘层。层的厚度为大约3微米。 </li><li>完全固化基板在80℃下2小时在对流烘箱。 </li><li>通过使用该方法在第2（ 图4C）的石墨烯转移至PDMS涂覆的ITO / PET基底上。 </li><li>通过使用该方法在第3（ 图4D）合成在基板上的双异质结构。 </li><li>旋涂的层的PDMS在500rpm，持续5秒，然后5000rpm下60秒，以改善在ZnO纳米棒的鲁棒性和耐久性，然后完全治愈它在80℃下进行2小时（图4E）。层的厚度是约8微米。 </li><li>覆盖ITO涂布的PET基片作为上电极（图4F）。 </li></ol> 5，电气性能测量设置注意:我们设置了定制设备的电气性能表征采用直线电机，工业规模和示波器。建立帧用于垂直支承线性马达，并将商业规模的线性电动机下，如图5A所示。规模应该是小，重量轻（0.02 KG - 20千克）很敏感。 <ol><li>将纳米发电机的规模，然后连接纳米发生器的电极以感测示波器的探头（图5A 和 5B）。 </li><li>设置线性电机的初始和最终位置和速度，同时密切监测重量中的比例。 提示:配置，其中纳米发电机轻微接触测量电初始位置键相设置。线性电动机的速度决定的应变速率。 </li><li>启动直线电机和监测随时间的电压信号。保存在闪速存储器中的时间相关的电压信号。应变速率:100毫米/秒和施加载荷:50N。 </li></ol>

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The authors declare that they have no competing financial interests.

请注意，高品质（&gt; 99.8％，退火）的Cu箔的应被视为一个基板单层石墨烯的成功生长。否则，单个石墨烯层是不均匀地在Cu箔长大，导致显着地减少在石墨烯的导电性。阿1小时退火的高温将有助于Cu箔结晶从Cu箔的任何污染物的提高以及去除。 的ZnO纳米棒的生长依赖于用于预热水热条件，因此，最佳浓度，温度和时间的增长必须仔细进行校准。六水合硝酸锌和HMT的浓度决定的ZnO纳米棒的直径，添加剂的PEI不仅提供以ZnO纳米棒的高宽比的提高也有利于连续的ZnO生长长时间17,18。 典型的独立单的SEM图像，双异质结构示于图6中。正如从这些图中可以看出，ZnO纳米棒的石墨烯的底部阵列开始12小时生长后增加，并且它们的长度线性地增加，从0.71至1.56微米。此外，ZnO纳米棒的石墨烯的顶部的长度，12小时之前被线性增加，然后向下生长的ZnO纳米棒的生长后饱和约2微米。这一结果表明，在ZnO纳米棒的生长遵循常规水热的方式12小时之前，但双异质开始12小时后为成长由于分解种子层和石墨烯19的空位缺陷。由于我们只是调节典型水热合成技术的生长时间来制作双异质结构，这里提出的方法可以用于其它水热生长的金属氧化物，如二氧化钛，的SnO 2和Fe 3 O 4等。 对于电气测量，就必须检查是否来自所制造的纳米发生器的电信号。纳米发电机和测量装置之间的摩擦带电导致的电噪声，并中断准确的观察压电性能。这避免了由精心配置，其中纳米发生器稍微接触测量装置的初始位置。 综上所述，本手稿详细介绍了制造的ZnO纳米棒/石墨烯/氧化锌纳米棒外延双异质结构的轻便协议。的通用方法来构造双异质结构可以提高的ZnO纳米棒的不仅数密度，而且双异质结构在给定的区域中的比表面积。这种方法利用了这样两个连续的生长技术来精确构造独特的纳米材料成空间布置结构，可以作为功能性材料的电子和光电应用的数量lications如触摸板电子，智能手套，可植入装置，以及生物传感器。

最近，便携式和可佩戴电子设备成为舒适的生活由于纳米技术的发展，这导致对于在微瓦到毫瓦的范围内的功率源的巨大需求的一个基本要素。可观的方法用于便携式和可穿戴设备的电源已经由可再生能源来实现，包括太阳能1,2-，3,4-热和机械源5,6。压电纳米发生器已被深入研究，作为可能的候选用于从环境中，如沙沙叶片7，声波8和人类被9运动能量采集设备之一。主原理的纳米发生器底层是压电潜力和介电材料作为阻挡之间的耦合。在应变材料中产生的压电势引起流经外部CIRC瞬变电流UIT，这在压电和介电材料之间的界面平衡的潜力。纳米发电机的性能将通过使用压电材料的纳米结构，由于在高应力和响应速度下的鲁棒性的鲁棒性，微小的变形10得到改善。 一维氧化锌纳米结构是一种很有前途的组件压电材料在纳米发电机由于其吸引人的特性， 例如 ，它的高压电（26.7分/ V）11，光学透明度12，和浅显的合成用化学方法13。种植了完全一致的ZnO纳米棒的水热方法受到很大的关注，因为成本低，环保的合成和潜在的易结垢起来。此外，预热水热技术是容易控制的实验条件下，从而导致多种新颖的纳米结构，如nanoleaves 14，纳米花15和纳米管16。新颖的纳米结构使在电气和光电装置只要材料的高比表面积要求的性能具有有益效果。 在这个协议中，我们描述了实验方法合成更新颖的纳米结构（即，独立的双异质结构）。的ZnO纳米棒的在石墨烯和聚对苯二甲酸乙酯（PET）的基底之间的界面生长导致自升在ZnO纳米棒/石墨烯单异质结构，得到了独立的双异质结构。此外，这种独特的纳米结构的电子和光电器件的可行的应用证明了制造压电纳米发电机。独立式的双异质结构不仅提供高的比表面积，而且纳米棒的给定区域中高数量密度。这种独特的纳米结构具有巨大的强效IAL为电气和光 - 电装置，如压力传感器，免疫传感器和染料敏化太阳能电池的应用程序。

<table border="0" cellpadding="0" cellspacing="0" width="573">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Cu foil</td>
			<td style="width:71px;">Alfa Aesar</td>
			<td align="right" style="width:119px;">13382</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">poly(methyl methacrylate) (PMMA)</td>
			<td style="width:71px;">Aldrich</td>
			<td align="right" style="width:119px;">182230</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">zinc nitrate hexahydrate</td>
			<td style="width:71px;">Sigma-Aldrich</td>
			<td align="right" style="width:119px;">228732</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">hexamethylenetetramine (HMT)</td>
			<td style="width:71px;">Sigma-Aldrich</td>
			<td align="right" style="width:119px;">398160</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">polyethylenimine (PEI)</td>
			<td style="width:71px;">Sigma-Aldrich</td>
			<td align="right" style="width:119px;">408719</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">indium tin oxide (ITO) coated PET</td>
			<td style="width:71px;">Aldrich</td>
			<td align="right" style="width:119px;">639303</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Silicone Elastomer Kit</td>
			<td style="width:71px;">Dow Corning</td>
			<td style="width:119px;">Sylgard 184 a, b</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Nickel Etchant Type1</td>
			<td style="width:71px;">Transene Company</td>
			<td align="right" style="width:119px;">41212</td>
			<td></td>
		</tr>
	</tbody>
</table>

preparation of zno nanorod/graphene/zno nanorod epitaxial double heterostructure for piezoelectrical nanogenerator by using preheating hydrothermal

那么对齐ZnO纳米结构已经深入研究过了显着的物理特性和巨大的应用在过去的十年。这里，我们描述一个一步法制造技术制合成独立式的ZnO纳米棒/石墨烯/氧化锌纳米棒双异质结构。双异质结构的制备是通过使用热化学气相沉积（CVD）和预热水热技术进行。此外，该形态性质通过使用扫描电子显微镜（SEM）。独立式双异质结构的效用表现为制造压电纳米发电机。电输出提高至200％相比，由于ZnO纳米棒的顶部和石墨烯的底部阵列之间的压电的耦合效应的单个异质结构。这种独特的双异质结构有巨大潜力的电气和光 - 电应用在需要高数密度与纳米棒的比表面积装置，如压力传感器，免疫传感器和染料敏化太阳能电池。

扫描电子显微镜（SEM） 图 6示出本的水热生长的ZnO纳米棒的形态的图像。预热水热技术可以导致两个不同的纳米结构根据生长时间。 图6A示出了上，以5小时的生长时间石墨烯/ PET基材的ZnO纳米棒的一个典型的图像。与此相反，在图6B所示的图像表明氧化锌纳米棒在12小时的生长时间的增长已成功进行不仅对石墨烯的顶部，而且在石墨烯的底部。两个ZnO纳米棒垂直对齐到石墨烯层，用2.49和0.70微米平均长度，分别为。此外，在石墨烯的底部的ZnO纳米棒的长度增加约2倍的生长时间增加至24小时， 如图6C所示。氧化锌纳米棒的底部澳增长˚F石墨烯进行了大规模（&gt; 30微米）上，产生自标高的ZnO纳米棒/石墨烯构建体，由此形成独立的双异质结构（图6D）。 图7A示出了压电纳米发生器，其组成的独立的双异质结构以及两个ITO涂布的PET基底的顶部和底部电极的照片。电输出源于纳米发生器，而不是测量系统，这是由极性切换测量（ 图7B和7C）证实。由ZnO纳米棒的顶部和石墨烯的底部阵列的输出电压，观察到0.5伏和0.3伏分别通过施加的49N（ 图7E和7F）周期性压缩释放负载。此外，两个的ZnO纳米棒的阵列产生的增强outpu吨的电压和电流以0.9 V和70 nA的分别的平均值。通过COMSOL包所执行的仿真结果表明，氧化锌纳米棒上的顶部和底部的石墨烯的极性是从实验和仿真（ 图7D）中得到的结果之间的反向和良好的一致性。 <img alt="图1" src="/files/ftp_upload/53491/53491fig1.jpg" /> 图1.生长单层石墨烯。（ 一）实验装置的热CVD的图像。 （二）在生长炉和单层石墨烯（C）成长一步铜箔的位置。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/53491/53491fig1large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图2" src="/files/ftp_upload/53491/53491fig2.jpg" /> 数字使用的捕鱼方法石墨烯转移2.工艺流程。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/53491/53491fig2large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图3" src="/files/ftp_upload/53491/53491fig3.jpg" /> 图3.合成工艺为独立双异质结构。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/53491/53491fig3large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图4" src="/files/ftp_upload/53491/53491fig4.jpg" /> 图4.原理制造工艺的压电纳米发电机的。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/53491/53491fig4large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> 图5.电气测量装置 （A）自制测量系统原理图和 （B）测量系统的照片。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/53491/53491fig5large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图6" src="/files/ftp_upload/53491/53491fig6.jpg" /> 水热生长的ZnO纳米棒的图6的SEM图像。（A）的5小时生长后的单异质结构。增长和 （D）立双异质结的12小时（B）和 24小时（C）后双异质结。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/53491/53491fig6large.jpg" target="_blank">请点击此处THI的放大版本。</a>的身影。 <img alt="图7" src="/files/ftp_upload/53491/53491fig7.jpg" /> 图7.压电纳米发电机代表性的结果。（A）制成的纳米发电机的照片。在正向（B）的输出电压和反向（C）的连接。 （ 四）COMSOL模拟压电势下沿轴向应变的ZnO纳米棒。纳米棒的尺寸是L = 600纳米和= 60纳米，外力是80 NN。输出电压（E）和纳米发电机的电流（F）。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/53491/53491fig7large.jpg" target="_blank">请点击此处查看该图的放大版本。</a>

Watch this Scientific Journal Video about Preparation of ZnO Nanorod/Graphene/ZnO Nanorod Epitaxial Double Heterostructure for Piezoelectrical Nanogenerator by Using Preheating Hydrothermal at JoVE.co

Preparation of ZnO Nanorod/Graphene/ZnO Nanorod Epitaxial Double Heterostructure for Piezoelectrical Nanogenerator by Using Preheating Hydrothermal

利用预热水热氧化锌纳米棒/石墨烯/氧化锌纳米棒外延双异质结的机压电纳米发电机的研制

一步法制备方法获得独立的外延双异质结构呈现。这种方法可以实现的ZnO覆盖率比外延单异质结构的更高的数密度，导致了压电纳米发电机具有增加输出电性能。

Well-aligned ZnO nanostructures have been intensively studied over the last decade for remarkable physical properties and enormous applications. Here, we ...

preparation-zno-nanorodgraphenezno-nanorod-epitaxial-double

Nanyang Technological University

Research

JoVE Journal

Engineering

12.5K 次观看.  Pusan National University (PNU), Miryang. 一步法制备方法获得独立的外延双异质结构呈现。这种方法可以实现的ZnO覆盖率比外延单异质结构的更高的数密度，导致了压电纳米发电机具有增加输出电性能。 

视频: Preparation of ZnO Nanorod/Graphene/ZnO Nanorod Epitaxial Double Heterostructure for Piezoelectrical Nanogenerator by Using Preheating Hydrothermal

Preparation and Use of Photocatalytically Active Segmented Ag|ZnO and Coaxial TiO2-Ag Nanowires Made by Templated Electrodeposition

Photocatalytically active nanostructures require a large specific surface area with the presence of many catalytically active sites for the oxidation and reduction half reactions, and fast electron (hole) diffusion and charge separation. Nanowires present suitable architectures to meet these requirements. Axially segmented Ag|ZnO and radially segmented (coaxial) TiO2-Ag nanowires with a diameter of 200 nm and a length of 6-20 &#181;m were made by templated electrodeposition within the pores of polycarbonate track-etched (PCTE) or anodized aluminum oxide (AAO) membranes, respectively. In the photocatalytic experiments, the ZnO and TiO2 phases acted as photoanodes, and Ag as cathode. No external circuit is needed to connect both electrodes, which is a key advantage over conventional photo-electrochemical cells. For making segmented Ag|ZnO nanowires, the Ag salt electrolyte was replaced after formation of the Ag segment to form a ZnO segment attached to the Ag segment. For making coaxial TiO2-Ag nanowires, a TiO2 gel was first formed by the electrochemically induced sol-gel method. Drying and thermal annealing of the as-formed TiO2 gel resulted in the formation of crystalline TiO2 nanotubes. A subsequent Ag electrodeposition step inside the TiO2 nanotubes resulted in formation of coaxial TiO2-Ag nanowires. Due to the combination of an n-type semiconductor (ZnO or TiO2) and a metal (Ag) within the same nanowire, a Schottky barrier was created at the interface between the phases. To demonstrate the photocatalytic activity of these nanowires, the Ag|ZnO nanowires were used in a photocatalytic experiment in which H2 gas was detected upon UV illumination of the nanowires dispersed in a methanol/water mixture. After 17 min&#160;of illumination, approximately 0.2 vol% H2 gas was detected from a suspension of ~0.1 g of Ag|ZnO nanowires in a 50 ml 80 vol% aqueous methanol solution.

Preparation and Use of Photocatalytically Active Segmented Ag|ZnO and Coaxial TiO2-Ag Nanowires Made by Templated Electrodeposition

Procedures are outlined to prepare segmented and coaxial nanowires via templated electrodeposition in nanopores. As examples, segmented nanowires consisting of Ag and ZnO segments, and coaxial nanowires consisting of a TiO2 shell and a Ag core were made. The nanowires were used in photocatalytic hydrogen formation experiments.

制备和使用光催化活性分段银|氧化锌和二氧化钛同轴<sub&gt; 2</sub&gt;银纳米线制成由模板电

Photocatalytically active nanostructures require a large specific surface area with the presence of many catalytically active sites for the oxidation and ...

科研

工程学

The Preparation of Electrohydrodynamic Bridges from Polar Dielectric Liquids

Horizontal and vertical liquid bridges are simple and powerful tools for exploring the interaction of high intensity electric fields (8-20 kV/cm) and polar dielectric liquids. These bridges are unique from capillary bridges in that they exhibit extensibility beyond a few millimeters, have complex bi-directional mass transfer patterns, and emit non-Planck infrared radiation. A number of common solvents can form such bridges as well as low conductivity solutions and colloidal suspensions. The macroscopic behavior is governed by electrohydrodynamics and provides a means of studying fluid flow phenomena without the presence of rigid walls. Prior to the onset of a liquid bridge several important phenomena can be observed including advancing meniscus height (electrowetting), bulk fluid circulation (the Sumoto effect), and the ejection of charged droplets (electrospray). The interaction between surface, polarization, and displacement forces can be directly examined by varying applied voltage and bridge length. The electric field, assisted by gravity, stabilizes the liquid bridge against Rayleigh-Plateau instabilities. Construction of basic apparatus for both vertical and horizontal orientation along with operational examples, including thermographic images, for three liquids (e.g., water, DMSO, and glycerol) is presented.

Horizontal and vertical electrohydrodynamic liquid bridges are simple and powerful tools for exploring the interaction of high intensity electric fields and polar dielectric liquids. The construction of basic apparatus and operational examples, including thermographic images, for three liquids (e.g., water, DMSO, and glycerol) is presented.

高压直流电桥从极地介电液的制备

Horizontal and vertical liquid bridges are simple and powerful tools for exploring the interaction of high intensity electric fields (8-20 kV/cm) and ...

Preparation and Friction Force Microscopy Measurements of Immiscible, Opposing Polymer Brushes

Solvated polymer brushes are well known to lubricate high-pressure contacts, because they can sustain a positive normal load while maintaining low friction at the interface. Nevertheless, these systems can be sensitive to wear due to interdigitation of the opposing brushes. In a recent publication, we have shown via molecular dynamics simulations and atomic force microscopy experiments, that using an immiscible polymer brush system terminating the substrate and the slider surfaces, respectively, can eliminate such interdigitation. As a consequence, wear in the contacts is reduced. Moreover, the friction force is two orders of magnitude lower compared to traditional miscible polymer brush systems. This newly proposed system therefore holds great potential for application in industry. Here, the methodology to construct an immiscible polymer brush system of two different brushes each solvated by their own preferred solvent is presented. The procedure how to graft poly(N-isopropylacrylamide) (PNIPAM) from a flat surface and poly(methyl methacrylate) (PMMA) from an atomic force microscopy (AFM) colloidal probe is described. PNIPAM is solvated in water and PMMA in acetophenone. Via friction force AFM measurements, it is shown that the friction for this system is indeed reduced by two orders of magnitude compared to the miscible system of PMMA on PMMA solvated in acetophenone.

The methodology to perform friction force microscopy experiments for contacting brushes is presented: Two polymer brushes that are grafted from (a) substrates and (b) colloidal probes are slid to show that, by using two contacting immiscible brush systems, friction in sliding contacts is reduced compared to miscible brush systems.

互溶的测量准备和摩擦力显微镜，反对聚合物刷

Solvated polymer brushes are well known to lubricate high-pressure contacts, because they can sustain a positive normal load while maintaining low ...

Synthesis and Characterization of High c-axis ZnO Thin Film by Plasma Enhanced Chemical Vapor Deposition System and its UV Photodetector Application

In this study, zinc oxide (ZnO) thin films with high c-axis (0002) preferential orientation have been successfully and effectively synthesized onto silicon (Si) substrates via different synthesized temperatures by using plasma enhanced chemical vapor deposition (PECVD) system. The effects of different synthesized temperatures on the crystal structure, surface morphologies and optical properties have been investigated. The X-ray diffraction (XRD) patterns indicated that the intensity of (0002) diffraction peak became stronger with increasing synthesized temperature until 400 oC. The diffraction intensity of (0002) peak gradually became weaker accompanying with appearance of (10-10) diffraction peak as the synthesized temperature up to excess of 400 oC. The RT photoluminescence (PL) spectra exhibited a strong near-band-edge (NBE) emission observed at around 375 nm and a negligible deep-level (DL) emission located at around 575 nm under high c-axis ZnO thin films. Field emission scanning electron microscopy (FE-SEM) images revealed the homogeneous surface and with small grain size distribution. The ZnO thin films have also been synthesized onto glass substrates under the same parameters for measuring the transmittance.
For the purpose of ultraviolet (UV) photodetector application, the interdigitated platinum (Pt) thin film (thickness ~100 nm) fabricated via conventional optical lithography process and radio frequency (RF) magnetron sputtering. In order to reach Ohmic contact, the device was annealed in argon circumstances at 450 oC by rapid thermal annealing (RTA) system for 10 min. After the systematic measurements, the current-voltage (I-V) curve of photo and dark current and time-dependent photocurrent response results exhibited a good responsivity and reliability, indicating that the high c-axis ZnO thin film is a suitable sensing layer for UV photodetector application.

We offered a method to directly synthesize high c-axis (0002) ZnO thin film by plasma enhanced chemical vapor deposition. The as-synthesized ZnO thin film combined with Pt interdigitated electrode was used as sensing layer for ultraviolet photodetector, showing a high performance through a combination of its good responsivity and reliability.

合成和高c轴ZnO薄膜等离子体的特性增强化学气相沉积系统及其紫外探测器的应用

In this study, zinc oxide (ZnO) thin films with high c-axis (0002) preferential orientation have been successfully and effectively synthesized onto ...

Subsurface Defect Localization by Structured Heating Using Laser Projected Photothermal Thermography

The presented method is used to locate subsurface defects oriented perpendicularly to the surface. To achieve this, we create destructively interfering thermal wave fields that are disturbed by the defect. This effect is measured and used to locate the defect. We form the destructively interfering wave fields by using a modified projector. The original light engine of the projector is replaced with a fiber-coupled high-power diode laser. Its beam is shaped and aligned to the projector&#39;s spatial light modulator and optimized for optimal optical throughput and homogeneous projection by first characterizing the beam profile, and, second, correcting it mechanically and numerically. A high-performance infrared (IR) camera is set up according to the tight geometrical situation (including corrections of the geometrical image distortions) and the requirement to detect weak temperature oscillations at the sample surface. Data acquisition can be performed once a synchronization between the individual thermal wave field sources, the scanning stage, and the IR camera is established by using a dedicated experimental setup which needs to be tuned to the specific material being investigated. During data post-processing, the relevant information on the presence of a defect below the surface of the sample is extracted. It is retrieved from the oscillating part of the acquired thermal radiation coming from the so-called depletion line of the sample surface. The exact location of the defect is deduced from the analysis of the spatial-temporal shape of these oscillations in a final step. The method is reference-free and very sensitive to changes within the thermal wave field. So far, the method has been tested with steel samples but is applicable to different materials as well, in particular to temperature sensitive materials.

This method aims at locating vertical subsurface defects. Here, we couple a laser with a spatial light modulator and trigger its video input to heat a sample surface deterministically with two anti-phased modulated lines while acquiring highly resolved thermal images. The defect position is retrieved from evaluating thermal wave interference minima.

使用激光投射光热法构造加热的地下缺陷定位

The presented method is used to locate subsurface defects oriented perpendicularly to the surface. To achieve this, we create destructively interfering ...

Well-aligned Vertically Oriented ZnO Nanorod Arrays and their Application in Inverted Small Molecule Solar Cells

This manuscript describes how to design and fabricate efficient inverted solar cells, which are based on a two-dimensional conjugated small molecule (SMPV1) and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM), by utilizing ZnO nanorods (NRs) grown on a high quality Al-doped ZnO (AZO) seed layer. The inverted SMPV1:PC71BM solar cells with ZnO NRs that grew on both a sputtered and sol-gel processed AZO seed layer are fabricated. Compared with the AZO thin film prepared by the sol-gel method, the sputtered AZO thin film exhibits better crystallization and lower surface roughness, according to X-ray diffraction (XRD) and atomic force microscope (AFM) measurements. The orientation of the ZnO NRs grown on a sputtered AZO seed layer shows better vertical alignment, which is beneficial for the deposition of the subsequent active layer, forming better surface morphologies. Generally, the surface morphology of the active layer mainly dominates the fill factor (FF) of the devices. Consequently, the well-aligned ZnO NRs can be used to improve the carrier collection of the active layer and to increase the FF of the solar cells. Moreover, as an anti-reflection structure, it can also be utilized to enhance the light harvesting of the absorption layer, with the power conversion efficiency (PCE) of solar cells reaching 6.01%, higher than the sol-gel based solar cells with an efficiency of 4.74%.

This manuscript describes how to design and fabricate efficient inverted SMPV1:PC71BM solar cells with ZnO nanorods (NRs) grown on a high quality Al-doped ZnO (AZO) seed layer. The well-aligned vertically oriented ZnO NRs exhibit high crystalline properties. The power conversion efficiency of solar cells can reach 6.01%.

定向定向 ZnO 纳米阵列及其在倒小分子太阳电池中的应用

This manuscript describes how to design and fabricate efficient inverted solar cells, which are based on a two-dimensional conjugated small molecule ...

Preparation of Liquid Crystal Networks for Macroscopic Oscillatory Motion Induced by Light

A strategy based on doped liquid crystalline networks is described to create mechanical self-sustained oscillations of plastic films under continuous light irradiation. The photo-excitation of dopants that can quickly dissipate light into heat, coupled with anisotropic thermal expansion and self-shadowing of the film, gives rise to the self-sustained deformation. The oscillations observed are influenced by the dimensions and the modulus of the film, and by the directionality and intensity of the light. The system developed offers applications in energy conversion and harvesting for soft-robotics and automated systems.
The general method described here consists of creating free-standing liquid crystalline films and characterizing the mechanical and thermal effects observed. The molecular alignment is achieved using alignment layers (rubbed polyimide), commonly used in the display manufacturing industry. To obtain actuators with large deformation, the mesogens are aligned and polymerized in a splay/bend configuration, i.e., with the director of the liquid crystals (LCs) going gradually from planar to homeotropic through the film thickness. Upon irradiation, the mechanical and thermal oscillations obtained are monitored with a high-speed camera. The results are further quantified by image analysis using an image processing program.

The goal of the protocol is to create liquid crystalline polymer films that can mechanically oscillate under continuous light irradiation. We describe in great detail the conception of free-standing films, from the liquid crystal alignment method to the photo-actuation. The experimental protocol applied to prepare this material is broadly applicable.

光诱导的宏观振荡运动液晶网络的制备

A strategy based on doped liquid crystalline networks is described to create mechanical self-sustained oscillations of plastic films under continuous ...

Additive Manufacturing of Functionally Graded Ceramic Materials by Stereolithography

An additive manufacturing technology is applied to obtain functionally graded ceramic parts. This technology, based on digital light processing/stereolithography, is developed within the scope of the CerAMfacturing European research project. A three-dimensional (3-D) hemi-maxillary bone-like structure is 3-D printed using custom aluminum oxide polymeric mixtures. The powders and mixtures are fully analyzed in terms of rheological behavior in order to ensure proper material handling during the printing process. The possibility to print functionally graded materials using the Admaflex technology is explained in this document. Field-emission scanning electron microscopy (FESEM) show that the sintered aluminum oxide ceramic part has a porosity lower than 1% and no remainder of the original layered structure is found after analysis.

This manuscript describes the processing of single multifunctional ceramic components (e.g., combinations of dense-porous structures) additively manufactured by stereolithography.

立体平版印刷法对功能分级陶瓷材料的添加剂制造

An additive manufacturing technology is applied to obtain functionally graded ceramic parts. This technology, based on digital light ...

Construction and Operation of a Light-driven Gold Nanorod Rotary Motor System

The possibility to generate and measure rotation and torque at the nanoscale is of fundamental interest to the study and application of biological and artificial nanomotors and may provide new routes towards single cell analysis, studies of non-equilibrium thermodynamics, and mechanical actuation of nanoscale systems. A facile way to drive rotation is to use focused circularly polarized laser light in optical tweezers. Using this approach, metallic nanoparticles can be operated as highly efficient scattering-driven rotary motors spinning at unprecedented rotation frequencies in water.
In this protocol, we outline the construction and operation of circularly-polarized optical tweezers for nanoparticle rotation and describe the instrumentation needed for recording the Brownian dynamics and Rayleigh scattering of the trapped particle. The rotational motion and the scattering spectra provides independent information on the properties of the nanoparticle and its immediate environment. The experimental platform has proven useful as a nanoscopic gauge of viscosity and local temperature, for tracking morphological changes of nanorods and molecular coatings, and as a transducer and probe of photothermal and thermodynamic processes.

Plasmonic gold nanorods can be trapped in liquids and rotated at kHz frequencies using circularly-polarized optical tweezers. Introducing tools for Brownian dynamics analysis and light scatteringspectroscopy leads to a powerful system for research and application in numerous fields of science.

轻型金纳米旋转电机系统的施工与运行

The possibility to generate and measure rotation and torque at the nanoscale is of fundamental interest to the study and application of biological and ...

An Efficient Method for Selective Desalination of Radioactive Iodine Anions by Using Gold Nanoparticles-Embedded Membrane Filter

Here, we demonstrate a detail protocol for the preparation of nanomaterials-embedded composite membranes and its application to the efficient and ion-selective removal of radioactive iodines. By using citrate-stabilized gold nanoparticles (mean diameter: 13 nm) and cellulose acetate membranes, gold nanoparticle-embedded cellulose acetate membranes (Au-CAM) have easily been fabricated. The nano-adsorbents on Au-CAM were highly stable in the presence of high concentration of inorganic salts and organic molecules. The iodide ions in aqueous solutions could rapidly be captured by this engineered membrane. Through a filtration process using an Au-CAM containing filter unit, excellent removal efficiency (&gt;99%) as well as ion-selective desalination result was achieved in a short time. Moreover, Au-CAM provided good reusability without significant decrease of its performances. These results suggested that the present technology using the engineered hybrid membrane will be a promising process for the large-scale decontamination of radioactive iodine from liquid wastes.

An efficient method for the rapid and ion-selective desalination of radioactive iodine in several aqueous solutions is described by using gold nanoparticles-immobilized cellulose acetate membrane filters.