This work was supported by the Air Force Office of Scientific Research Young Investigator Research Program (AFOSR, Grant. No. FA9550-15-1-0301).

注意:在这些过程中使用的若干化学品（如浓硝酸（15.698中号HNO 3）和盐酸（6M HCl中））是危险的。适当的手套，护目镜等安全设备必须使用。使用前请参考所有化学品的材料安全数据表（MSDS）。 1.纳米立方体合成<ol><li> 试剂的制备 注:乙二醇（EG），必须是无水的。关闭EG容器的盖子时，它不使用，以防止水分的吸收。三氟乙酸银（AGC 2 F 3 O 2），是非常敏感的点亮，因此在AGC 2 F 3 O 2的溶液中的最后一个步骤制备。 <ol><li>通过在13.5毫升EG 1毫克的NaSH溶于制备1.3毫硫氢化钠水合物（NASH）溶液。 </li><li>通过在5ml乙二醇为0.1g的PVP溶解制备20毫克/毫升的聚乙烯吡咯烷酮（PVP）溶液。 </li><li>准备3毫米HY通过混合2.5微升的6.0米液体HCl溶液与4.9975毫升的EG drochloric溶液。 </li><li>由于0.8ml EG为0.1g银石墨2 F 3 O 2的溶解准备银石墨2 F 3 O 2的解决方案。 </li></ol></li><li> 设备安装 <ol><li>清洗圆底烧瓶（RBF）和其用浓帽（70％，15.698 M）硝酸HNO 3。装满HNO 3 RBF和放帽上30分钟。确保盖接触的酸。 </li><li>经过HNO 3酸，用干净的去离子（DI）水清洗一遍RBF和盖 ​​。用干净的氮气干燥RBF和帽子之后。 RBF和其上限必须是清洁和干燥。 </li><li>通过在HNO 3中浸渍30分钟，清洁磁性搅拌棒。 HNO 3后，用去离子水清洗一遍，然后用干净的氮气吹干。 </li><li>准备加热浴。放置一个硅氧烷流体浴（在图1A中示出）上具有良好控制的温度下搅拌加热板的顶部。使用外部温度计监视流体浴的温度。设定温度至150℃，搅拌速度至260转。 </li><li>用夹子安装RBF 如图1B。放置磁性搅拌棒（步骤1.2.3准备）到RBF。 </li></ol></li><li> 合成过程 <ol><li>浸RBF进入加热浴（深约10mm进液;参见图1A-1B）。 </li><li>使用一个微量吸移管至10毫升的EG溶液放入RBF。戴上RBF盖子，等待20分钟。这一步骤的目的是为了重新清洁RBF，此时用EG。 </li><li> 20分钟后，取下瓶盖，然后抬起RBF加热锅中，倒入10毫升EG进入处理容器。注意:EG溶液是热的（150℃），它建议采取整个钳出（ 图1B）。确保日在磁性搅拌棒（见步骤1.2.5）不会脱落。 </li><li>把RBF回热浴（见步骤1.3.1）。 </li><li>用微量到5ml的EG放入RBF装上盖子。 </li><li>等待5分钟。 </li><li>就拿RBF的帽子摘下，用微量放置60微升纳什（如上面的步骤1.1.1制备）进入RBF。把盖子重新拧上。 </li><li>等待2分钟。 </li><li>取RBR的帽脱落，使用微量吸管放置500微升的HCl溶液（如上面步骤1.1.3制备）进入的RBF。 </li><li>前面的步骤之后，立即使用一个微量吸移管以放置1.25毫升PVP的溶液（如上面步骤1.1.2制备）进入的RBF。把盖子重新拧上。 </li><li>等待2分钟。 </li><li>就拿RBF的帽子摘下，用微量放置400微升将AGC 2 F 3 O 2溶液（如上面的步骤1.1.4制备）进入RBF。把盖子重新拧上。 </li><li>等待2。5小时。银纳米立方体是在此步骤中形成。如果可能的话，在此期间，在室内光线减少到最低限度。 </li><li> 2.5小时后，关闭加热器，但留在搅拌，以避免在底部流体燃烧。使用夹子（ 图1B所示），以提高加热浴上方的RBF。取下盖子。 </li><li>拆下热浴，这样会更快冷静下来的RBF。经过约20分钟，加入5毫升丙酮进入RBF。涡它以良好混合的解决方案。在结束时，将溶液的总体积为12毫升见图2A。 </li><li>使用微量吸和最终溶液转移至八个小1.5毫升塑料管。 </li><li>在5150 xg的为10分钟的速度离心这八个管。其结果是，所有的银纳米立方体将在管的底部。使用一个微量吸移管在各管的底部，除去顶部上清液，留下约100微升。 </li><li>填1毫升DI水到每个这些管（从步骤1.3.17获得）。涡和超声（5分钟）管。现在纳米立方体悬浮于主要DI水中。 </li><li>离心再次在5150 XG在步骤1.3.18制备5分钟的八个管。所有的银纳米立方体将在管的底部。使用微量吸管，除去顶部上清液，留下约100微升在每个管的底部。 </li><li>填1毫升DI水到每个从步骤1.3.19中得到的管。涡和超声管。纳米立方体现在悬浮在去离子水。从该合成得到的最终纳米立方体溶液示于图2B，例如， </li></ol></li></ol> 2.金膜蒸发 注意:一个电子束蒸发器，使用上购买的洁净室清洁载玻片以沉积金（Au）膜，用铬（Cr）作为粘接层。蒸发过程发生在一个真空室，使分子能够自由蒸发在腔室，然后升华在衬底上。操作步骤是: <ol><li>发泄室，按"自动排气阀"。 </li><li>在穹顶打开室门和负载基板。 </li><li>关上门，然后按"自动泵"抽空，大约需要1小时的室内抽空，直到压力低于5×10 -6托。 </li><li>编辑配方。层＃1:铬，厚度:5nm时，沉积速率:1埃/秒;层＃2:金，厚度:50nm，沉积速率:2埃/秒。 </li><li>在达到所需的真空水平，第一金属的沉积过程将自动通过按下"自动运行"启动。 注意:在沉积，高电压模块被接通，电压为10千伏。枪旋转模块被接通时，和夹具旋转20转。第一层完成后，系统会自动移动到第二金属的口袋地点和开始deposi化。 </li><li>整个过程完成后，按"自动排气阀"宣泄室，并采取样品出来。 注意:Au膜的总厚度为50纳米，使用原子力显微镜（AFM）得到的典型的均方根（RMS）为0.7纳米，测定表面粗糙度。 Au膜沉积之前购买的玻璃基板，没有进行特殊处理。 </li></ol> 3. PE层的沉积<ol><li> 试剂的制备 <ol><li>为氯化钠（NaCl）溶液，混合29用500毫升DI水的克NaCl粉末。 </li><li>对于聚苯乙烯磺酸（PSS）解决方案，混合29克氯化钠粉用500毫升去离子水的再加入PSS原液1.5ml的。 </li><li>对于聚（烯丙基胺）盐酸盐（PAH）的解决方案，混合29克氯化钠粉用500毫升去离子水的再加入132毫克PAH的。 </li></ol></li><li> 层-层沉积 注意:PAH而PSS略微带负电荷的稍微带正电。如上述第2节制造的Au膜略微带负电，一个PAH层将首先沉积。步骤下面将详细说明如何存5 PE层:PAH / PSS / PAH / PSS / PAH。 <ol><li>首先，通过5分钟浸渍金膜（上述第2制成）成的PAH溶液（在步骤3.1.3制备）沉积PAH层。这导致了PAH层上的Au膜的顶部的厚度为〜1纳米。 </li><li> 5分钟后，用清洁的去离子水在Au膜+ 1的PAH层。 </li><li>沉浸在Au膜+ 1的PAH层成NaCl溶液（在步骤3.1.1制备）1分钟。 </li><li>沉浸Au膜+ 1层PAH（步骤3.2.3之后）到5分钟PSS的解决方案。这导致具有对PAH层的顶部的厚度为〜1nm的PSS层。 </li><li> 5分钟后，用清洁的去离子水在Au膜+ 1的PAH层+1 PSS层。 </li><li>沉浸在Au FILm + 1个的PAH层+1 PSS层到1分钟的NaCl溶液。 </li><li>沉浸在Au膜+ 1的PAH层+1 PSS层到5分钟的PAH溶液。这导致具有对PSS层的顶部的厚度为〜1nm的另一个PAH层（在步骤3.2.4制备上文）。 </li><li> 5分钟后，冲洗Au膜+1 PAH用干净的去离子水+1 PSS + 1的PAH层。 </li><li>沉浸在Au膜+ 1的PAH + 1的PSS + 1的PAH层到1分钟的NaCl溶液。 </li><li>沉浸在Au膜+ 1的PAH + 1的PSS + 1的PAH层到5分钟的PAH溶液。这导致具有对PAH层（其在步骤3.2.7上面制备的）的顶部的厚度为〜1nm的第二PSS层。 </li><li> 5分钟后，冲洗Au膜+1多环芳烃+1 PSS + 1的PAH + 1的PSS用干净的去离子水层。 </li><li>沉浸Au膜+ 1 PAH + 1 PSS + 1 PAH +1 PSS层到1分钟的NaCl溶液。 </li><li>沉浸在Au膜+ 1的PAH + 1的PSS + 1的PAH +1 PSS层到5分钟的PAH溶液。这一结果S IN与在PSS层（其在步骤3.2.10上面制备的）的顶部的厚度为〜1nm的另一个PAH层。 </li><li>最后，冲洗Au膜+ 1 PAH + 1 PSS + 1 PAH +1 PSS + 1 PAH离子水和清洁使用氮气干燥样品。 注意:五个PE层的总厚度是使用分光椭率计在65°的入射角在空气中测量，70°，和75°，得到的厚度为5.0±0.1纳米。 </li></ol></li></ol> 4.沉积Cy5的染料分子<ol><li>准备用DI水25μMCy5的溶液作为溶剂。 </li><li>暴露样品的表面（其具有一系列五个PE层，如在上述第3节中描述）进行10分钟至100微升25微米的Cy5溶液。首降100投微升Cy5的解决方案（步骤4.1制备）到样品表面，然后放置在滴液顶部盖玻片。 Cy5的分子将整合入T他顶PE层均匀。 </li><li> 10分钟后，漂洗用DI水样品并用干净氮气干燥。 </li></ol> 5.沉积纳米立方体，形成Nanopatch天线（不良资产） <ol><li>通过使用去离子水，使不良资产个体的光学研究中的1/100稀释因素，从第1节中获得的纳米立方体的解决方案。 </li><li>使用微量吸管，以20微升稀释纳米立方体溶液（在步骤5.1中制备）一滴放置到干净的盖玻片。放置在与盖滑移2分钟接触样品（第4制得）。此结果在所述Ag纳米立方体要在顶终端的PAH层上固定的，因为在这里所合成的纳米立方体被带负电荷的和顶部的PAH层带正电。 </li><li> 2分钟后，冲洗用DI水和干燥用干净氮气样品。 注:步骤5.1 - 5.3描述了一个步骤，使用暗场以制备用于单不良资产的光学研究的样本icroscope（暗场散射）。以制备用于反射测量的样品被施加不同的是在步骤5.1类似的程序的原始纳米立方体溶液通过的1/10，而不是1/100倍稀释。 </li></ol> 6.光学测量 注意:定制光学bright- /暗视野显微镜在这些测量中使用。的国家行动计划是由白色光源通过一长工作距离bright- /暗场目标照亮。从不良资产的反射/散射光由同一物镜收集。针孔孔径（直径50微米）用于在图像平面从个体nanoantenna选择信号。的数字照相机用于拍摄彩色图像。的能谱仪，和一个电荷耦合器件（CCD）照相机被用来获取光谱数据。用于荧光测量，633纳米连续波氦氖激光器被用于激发和信号被频谱由长通滤波器滤波。 <ol&gt; <li> 单不良资产暗场散射光谱 <ol><li>在白光照明下，识别在章节5在白光照明下制备的样品单不良资产， 如图4C个别不良资产显示为亮点，红色或粉红色圆点。 </li><li>对准一个NPA使用翻译阶段针孔。确保NPA的暗场散射像针孔孔径后，仍在观察。 </li><li>获得从NPA使用光谱仪和CCD照相机以1秒的积分时间的散射光的光谱。因为光圈区域（50微米）大于NPA的物理尺寸大得多（〜75纳米）的频谱含有散射光从NPA除了从围绕NPA的区域的信号。 </li><li>移动样品的区域，没有任何不良资产，并获得了1秒的积分时间另一个光谱。该光谱表示从散射光背景。 </li><li>与不良资产取下样品，并放置在设置一个认证的反射率标准样品。获得的散射光用0.1秒的积分时间的频谱以正常化从NPA的信号。 </li><li>关闭针孔光圈和获得具有0.1秒的积分时间的频谱没有任何输入信号。该频谱代表CCD暗计数。 </li><li>计算一个NPA的最后散射光谱如下: <img alt="式（1）" src="/files/ftp_upload/53876/53876eq1.jpg" /> 在这里我NPA +背景 ， 我的背景 ， 我的白光 ， 我CCD暗是分步6.1.3，6.1.4，6.1.5分别6.1.6和测得的散射光谱。 </li><li>通过计算散射共振峰的质心提取NPA的等离子体共振。16 </li></ol></li><li> Cy5的分子的荧光增强由单个n功率放大器<ol><li>在白光照明下，从第5节在暗场制备的样品标识单不良资产， 如图4C个别不良资产显示为亮点，红色或粉红色圆点。 </li><li>对准一个NPA使用翻译阶段针孔。确保NPA的暗场散射图像由摄像机放置在针孔之后检测到。 </li><li>关闭白光照明和打开用于激发的633nm的连续波氦氖激光器。 </li><li>为了阻止任何散射的激光入射到光谱仪之前正确放置在光路633纳米长传激光滤波器。 </li><li>获取来自使用1秒的积分时间的Cy5的分子发射的荧光光谱。因为光圈区域（50微米）比NPA（〜75纳米）的物理尺寸大得多该频谱包含从嵌入在NPA为WEL两种分子发射l由于周边NPA分子。 </li><li>移动样品的区域，没有任何不良资产，并获得了1秒的积分时间另一个光谱。这个频谱表示在后台分子的发射，而没有任何不良资产。 </li><li>准备一个单独的样品，其将被用作对照样品，以下内容，其中的Cy5分子结合用PE层在载玻片上的顶部（​​没有Au膜和Ag纳米立方体）在第3和第4的过程。 </li><li>获取来自Cy5的分子在用10秒的积分时间的前一步骤中制备的对照样品发射的荧光光谱。 </li><li>通过使用在步骤6.2.5，6.2.6和6.2.8测量的荧光光谱，同时考虑到由单位面积和采集时间在CCD暗计数，正规化判定12,14的荧光增强因子。 </li></ol></li></ol>

<ol>
	<li>Fan, J. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Self-Assembled+Plasmonic+Nanoparticle+Clusters.">Self-Assembled Plasmonic Nanoparticle Clusters.</a> Science. 328 (5982), 1135-1138 (2010).</li><li>Zhang, Q., Li, W., Wen, L. -. P., Chen, J., Xia, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Facile+Synthesis+of+Ag+Nanocubes+of+30+to+70+in+Edge+Length+with+CF3COOAg+as+a+Precursor.">Facile Synthesis of Ag Nanocubes of 30 to 70 in Edge Length with CF3COOAg as a Precursor.</a> Chem. Eur. J. 16 (33), 10234-10239 (2010).</li><li>Sun, Y., Xia, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Shape-Controlled+Synthesis+of+Gold+and+Silver+Nanoparticles.">Shape-Controlled Synthesis of Gold and Silver Nanoparticles.</a> Science. 298 (5601), 2176-2179 (2002).</li><li>Xia, Y., Halas, N. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Shape-Controlled+Synthesis+and+Surface+Plasmonic+Properties+of+Metallic+Nanostructures.">Shape-Controlled Synthesis and Surface Plasmonic Properties of Metallic Nanostructures.</a> MRS Bull. 30 (05), 338-348 (2005).</li><li>Ciraci, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Probing+the+Ultimate+Limits+of+Plasmonic+Enhancement.">Probing the Ultimate Limits of Plasmonic Enhancement.</a> Science. 337 (6098), 1072-1074 (2012).</li><li>Chandran, S. P., Chaudhary, M., Pasricha, R., Ahmad, A., Sastry, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis+of+Gold+Nanotriangles+and+Silver+Nanoparticles+Using+Aloevera+Plant+Extract.">Synthesis of Gold Nanotriangles and Silver Nanoparticles Using Aloevera Plant Extract.</a> Biotechnol. Prog. 22 (2), 577-583 (2006).</li><li>Perez-Juste, J., Pastoriza-Santos, I., Liz-Marz&#225;n, L. M., Mulvaney, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gold+nanorods:+Synthesis,+characterization+and+applications.">Gold nanorods: Synthesis, characterization and applications.</a> Coord. Chem. Rev. 249 (17-18), 1870-1901 (2005).</li><li>Nikoobakht, B., El-Sayed, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preparation+and+Growth+Mechanism+of+Gold+Nanorods+(NRs)+Using+Seed-Mediated+Growth+Method.">Preparation and Growth Mechanism of Gold Nanorods (NRs) Using Seed-Mediated Growth Method.</a> Chem. Mater. 15 (10), 1957-1962 (2003).</li><li>Rycenga, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Controlling+the+Synthesis+and+Assembly+of+Silver+Nanostructures+for+Plasmonic+Applications.">Controlling the Synthesis and Assembly of Silver Nanostructures for Plasmonic Applications.</a> Chem. Rev. 111 (6), 3669-3712 (2011).</li><li>Cortie, M. B., McDonagh, A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis+and+Optical+Properties+of+Hybrid+and+Alloy+Plasmonic+Nanoparticles.">Synthesis and Optical Properties of Hybrid and Alloy Plasmonic Nanoparticles.</a> Chem. Rev. 111 (6), 3713-3735 (2011).</li><li>Halas, N. J., Lal, S., Chang, W. -. S., Link, S., Nordlander, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Plasmons+in+Strongly+Coupled+Metallic+Nanostructures.">Plasmons in Strongly Coupled Metallic Nanostructures.</a> Chem. Rev. 111 (6), 3913-3961 (2011).</li><li>Rose, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Control+of+Radiative+Processes+Using+Tunable+Plasmonic+Nanopatch+Antennas.">Control of Radiative Processes Using Tunable Plasmonic Nanopatch Antennas.</a> Nano Lett. 14 (8), 4797-4802 (2014).</li><li>Akselrod, G. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Probing+the+mechanisms+of+large+Purcell+enhancement+in+plasmonic+nanoantennas.">Probing the mechanisms of large Purcell enhancement in plasmonic nanoantennas.</a> Nature Photon. 8 (11), 835-840 (2014).</li><li>Hoang, T. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ultrafast+spontaneous+emission+source+using+plasmonic+nanoantennas.">Ultrafast spontaneous emission source using plasmonic nanoantennas.</a> Nat. Commun. 6, (2015).</li><li>Akselrod, G. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Leveraging+Nanocavity+Harmonics+for+Control+of+Optical+Processes+in+2D+Semiconductors.">Leveraging Nanocavity Harmonics for Control of Optical Processes in 2D Semiconductors.</a> Nano Lett. 15 (5), 3578-3584 (2015).</li><li>Mock, J. J., Hill, R. T., Tsai, Y. -. J., Chilkoti, A., Smith, D. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Probing+Dynamically+Tunable+Localized+Surface+Plasmon+Resonances+of+Film-Coupled+Nanoparticles+by+Evanescent+Wave+Excitation.">Probing Dynamically Tunable Localized Surface Plasmon Resonances of Film-Coupled Nanoparticles by Evanescent Wave Excitation.</a> Nano Lett. 12 (4), 1757-1764 (2012).</li><li>Skrabalak, S. E., Au, L., Li, X., Xia, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Facile+synthesis+of+Ag+nanocubes+and+Au+nanocages.">Facile synthesis of Ag nanocubes and Au nanocages.</a> Nat. Protocols. 2 (9), 2182-2190 (2007).</li><li>Im, S. H., Lee, Y. T., Wiley, B., Xia, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Large-Scale+Synthesis+of+Silver+Nanocubes:+The+Role+of+HCl+in+Promoting+Cube+Perfection+and+Monodispersity.">Large-Scale Synthesis of Silver Nanocubes: The Role of HCl in Promoting Cube Perfection and Monodispersity.</a> Angew. Chem. Int. Ed. 44 (14), 2154-2157 (2005).</li><li>Moreau, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Controlled-reflectance+surfaces+with+film-coupled+colloidal+nanoantennas.">Controlled-reflectance surfaces with film-coupled colloidal nanoantennas.</a> Nature. 492 (7427), 86-89 (2012).</li><li>Lassiter, J. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Plasmonic+Waveguide+Modes+of+Film-Coupled+Metallic+Nanocubes.">Plasmonic Waveguide Modes of Film-Coupled Metallic Nanocubes.</a> Nano Lett. 13 (12), 5866-5872 (2013).</li></ol>

The authors declare that they have no competing financial interests.

使用类似于以前报道的合成反应条件的银纳米立方体进行化学合成。2,12,17-20这种合成能够与侧长度从50到100nm纳米立方体的制造。例如，2.5小时的一个典型的加热时间，将导致与〜75毫微米的边长纳米立方体。更长的合成时间（&gt; 3小时）将导致较大的纳米颗粒，但是，这也可能导致不同的形状，例如截纳米立方体或八面体。最终的溶液离心并重新悬浮于去离子水，并且可以在4℃下没有在等离子共振的散射光谱的任何明显的变化被存储在至少一个月的冰箱12中从在上述协议呈现的过程中的Ag纳米立方体的尺寸和形状是与RBF，它的帽和搅拌棒的清洁以及EG溶液的质量非常敏感。 Nanoparti不同形状，如圆形或长形的纳米颗粒克莱斯是一个迹象，表明有可能存在与在合成这些步骤之一的问题。因此，建议的步骤1.1.1-1.1.4和1.2.1-1.2.2是非常重要的。 在图4b从单个nanopatch天线所收集的散射光谱示其中在650nm处表现出强等离子体共振。这种共振指示所述Ag纳米立方体和高质量纳米立方体成为可能Au膜之间的间隙区域的优良模式限制。此外，获得这样的光谱，它也要求在样品是干净的，间隔层（PE层）具有均匀的厚度和底层Au膜是平滑的。强等离子体共振是由在图4c中呈现的数据，其中个别nanopatch天线可在暗视场图像和图4d可观察进一步证实，其中大的荧光增强观察位于间隙区域Cy5的分子。还应当指出的是，银纳米立方体氧化在一段时间，尽管PVP的涂层在暴露于空气中，因此建议的光学测量应在一天制备的样品或在1至3天来进行。为了最大限度地减少氧化，它建议nanopatch天线样本被存储在真空或氮气。 在本文所提出的方法使得银纳米立方体和电浆nanopatch天线与利用胶体合成和层 - 层浸涂工艺控制良好的尺寸制造。与其它技术如光学或电子束光刻相比，同时产生的纳米颗粒的粒径分布窄这里提出的技术提供了低成本和大规模生产的潜力。 本文提出电浆nanopatch天线也保持巨大潜力通过设计新的纳米材料，呈现出可能在他们的同行宏观存在的独特性质。特别是，这些纳米天线显示嵌入式染料分子超过30,000创纪录的高荧光增强; 1000 12自发辐射率增强功能;超快自发发射和高量子产率。13,14此外，已经显示，发射极耦合到这些nanopatch天线表现出高度定向的发射是用于其中需要耦合到外部检测器或单模光纤的应用是至关重要的。纳米级贴片天线的未来应用可能12-14范围从超快光电子器件，如发光二极管，以高效率的光电检测器和光伏器件，传感和量子信息处理技术。

近年来，纳米胶体合成，这些装配到高级的结构无论是在科研和工业发展已经引起了极大的兴趣。1-4纳米胶体合成了光刻制造的纳米结构，包括优越的尺寸均一性，成本低，有几大优势大规模，平行生产的可能性。 金属纳米颗粒如银（Ag）和金（Au）可以支持局部表面等离子体激元和在一个体积比衍射极限小得多，以限制光的能力。1,3-5所得高场强度创建增强型本地国家使光与物质相互作用的密度在纳米尺度上进行调整。最近的努力已经证明程序来合成Ag和Au纳米颗粒在宽范围的尺寸和形状，包括三角形，4,6-笼，3,4-和棒4,7,8除了这里讨论的纳米立方体。的几个Ag或Au nanocomponents由纳米结构也已制造示范定制属性。1,9-11 在这里，我们证明一个过程来合成银纳米立方体，更重要的是，为连接这些的Ag纳米立方体与下面Au膜以形成电浆nanopatch天线。银纳米立方体和Au膜之间的距离可与〜1纳米的分辨率通过使用一系列聚电解质隔离层来控制。我们还证明如何将活性介质中，例如有机染料，成电浆nanopatch天线。由于在纳米立方体和Au膜之间的间隙区域的强烈密闭电磁场，所述nanopatch天线可用于高度增强嵌入染料分子的荧光和自发发射。12,13在本文提出的方法可以推广其他发射器，SUCH作为胶体固态量子点14或二维半导体材料，15和等离子体共振可以在很宽的光谱范围内通过改变纳米立方体或间隙的尺寸进行调整。

<table>
	<tbody>
		<tr>
			<td>Reagents</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Ethylene glycol&#160;</td>
			<td>J.T. Baker</td>
			<td>9300</td>
			<td>Must be anhydrous</td>
		</tr>
		<tr>
			<td>Sodium hydrosulfide hydrate&#160;&#160;</td>
			<td>Sigma Aldrich</td>
			<td>161527</td>
			<td></td>
		</tr>
		<tr>
			<td>Poly vinylpyrrolidone&#160;</td>
			<td>Sigma Aldrich</td>
			<td>856568</td>
			<td></td>
		</tr>
		<tr>
			<td>Hydrochroric acid BDH ARISTAR PLUS</td>
			<td>VWR International</td>
			<td>7647-01-0</td>
			<td></td>
		</tr>
		<tr>
			<td>Silver trifluoroacetate&#160;</td>
			<td>Sigma Aldrich</td>
			<td>482307</td>
			<td>Store in dark place</td>
		</tr>
		<tr>
			<td>Acetone</td>
			<td>Sigma Aldrich</td>
			<td>48358</td>
			<td></td>
		</tr>
		<tr>
			<td>Nitric acid&#160;</td>
			<td>Sigma Aldrich</td>
			<td>7697-37-2</td>
			<td>&#160;concentrated (70%), for cleaning</td>
		</tr>
		<tr>
			<td>Poly(allylamine) hydrochloride (PAH)</td>
			<td>Sigma-Aldrich</td>
			<td>283215</td>
			<td></td>
		</tr>
		<tr>
			<td>Polystyrene sulfonate&#160; (PSS)</td>
			<td>Sigma-Aldrich</td>
			<td>561223</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium Chloride&#160;</td>
			<td>Macron Inc.</td>
			<td>7647</td>
			<td></td>
		</tr>
		<tr>
			<td>Sulfo-Cyanine5 carboxylic acid (Cy5)</td>
			<td>Lumiprobe</td>
			<td>13390</td>
			<td>Fluorescent dye (molecular weight: 664.76 g/mol)</td>
		</tr>
		<tr>
			<td>Equipments</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Stirring hotplate with temperature control</td>
			<td>VWR International</td>
			<td>89000-338</td>
			<td></td>
		</tr>
		<tr>
			<td>Vortex mixers</td>
			<td>VWR International</td>
			<td>10153-834</td>
			<td></td>
		</tr>
		<tr>
			<td>Microcentrifuge</td>
			<td>Thermoscientific</td>
			<td>Model 59A</td>
			<td></td>
		</tr>
		<tr>
			<td>Silicone fluid&#160;</td>
			<td>Sigma-Aldrich</td>
			<td>63148-62-9</td>
			<td></td>
		</tr>
		<tr>
			<td>Micro-scale</td>
			<td>Mettler Toledo</td>
			<td>Model ML 104/03</td>
			<td></td>
		</tr>
		<tr>
			<td>Electron-beam metal evaporator&#160;</td>
			<td>CHA Industries</td>
			<td>E-beam evaporator</td>
			<td>Located inside a clean room</td>
		</tr>
		<tr>
			<td>Pre-cleaned glass slides</td>
			<td>Schott North America, Inc.</td>
			<td>Nexterion Glass B&#160;</td>
			<td>Clean room pre-cleaned</td>
		</tr>
		<tr>
			<td>25-mL 24/40 round-bottle flask&#160;</td>
			<td>VWR International</td>
			<td>60002-290</td>
			<td></td>
		</tr>
		<tr>
			<td>Magnetic stirring bar</td>
			<td>VWR International</td>
			<td>58948-116</td>
			<td></td>
		</tr>
		<tr>
			<td>Micropipettes (1-10mL, 10&#8211;100 mL and 100&#8211;1000 mL)</td>
			<td>VWR International</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Ultrasonic cleaning bath</td>
			<td>Branson Ultrasonic</td>
			<td>Model 1510R-DTH</td>
			<td></td>
		</tr>
		<tr>
			<td>Stopwatch</td>
			<td>VWR International</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Eppendorf centrifugation tubes (1.5 mL)</td>
			<td>VWR International</td>
			<td>22364111</td>
			<td></td>
		</tr>
		<tr>
			<td>Poly(propylene) coning tubes (50 mL)</td>
			<td>VWR International</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Home built bright/darkfield microscope</td>
			<td></td>
			<td></td>
			<td>75 W Xenon white light source, Nikon BF/DF 50x ELWD 
			0.55 NA, 8.2 mm WD objective, Nikon D90 digital camera, Acton 2300i spectrometer, Photometrics CoolSnap HQ&#160; charge coupled device (CCD) camera</td>
		</tr>
		<tr>
			<td>He Ne laser (633 nm), 5 mW</td>
			<td>New Port Co.</td>
			<td>R-30990</td>
			<td></td>
		</tr>
		<tr>
			<td>Reflectance standard</td>
			<td>Lab Sphere</td>
			<td>Model SRS-99-010</td>
			<td></td>
		</tr>
		<tr>
			<td>Laser long pass filter 633 nm</td>
			<td>Semrock</td>
			<td>LP02-633RU-25</td>
			<td></td>
		</tr>
	</tbody>
</table>

colloidal synthesis of nanopatch antennas for applications in plasmonics and nanophotonics

我们提出了一种用于银纳米立方体的胶体合成或组合使用这些具有光滑金膜，以制造电浆纳米贴片天线。这包括薄膜具有良好控制的厚度比使用层 - 层聚电解质的聚合物，沉积即聚（烯丙胺）盐酸盐（PAH），聚苯乙烯磺酸盐（PSS）宏观区域的制造的详细过程。这些聚电解质隔离层作为在银纳米立方体和金膜之间的介电间隙。通过控制纳米立方体或间隙厚度的尺寸，等离子体共振可从约500纳米被调谐到700纳米。接下来，我们将演示如何将有机磺基cyanine5羧酸（Cy5的）染料分子进入nanopatch天线的电介质聚合物间隙区域。最后，我们表明大大通过用激发能量和叔频谱匹配等离子体共振增强的Cy5染料的荧光他Cy5的吸收峰。这里介绍的方法，使等离子nanopatch天线与利用胶体合成和与低成本和大规模生产的潜力的层 - 层浸涂工艺控制良好的尺寸制造。这些nanopatch天线在实际应用中具有很大的希望，例如在传感，超快光电子器件和高效率的光电探测器。

这里，我们显示的电浆nanopatch天线的特性的代表性结果，其中将样品结构的SEM图像，nanopatch天线的集合的反射光谱并从单一nanopatch天线的散射光谱。所述nanopatch天线的等离子体共振的能量依赖于纳米立方体的大小，电介质间隙区域的厚度， 即 ，聚乙烯层的数目，以及介电材料。在提出的上述我们得到的Ag纳米立方体为75纳米的平均边长和稍微圆角的程序（曲率半径〜10纳米）涂覆在用1-3纳米的估计厚度的PVP层。与5的PE层和金膜，这一结果在〜650nm处具有全宽在半最大值的〜50纳米（FWHM）为中心的等离子共振结合。这又具有与T的吸收和发射波长良好光谱重叠他CY5这是在646和662 nm处为中心，分子。 图3A示出了具有纳米立方体的高浓度的样品的SEM图像。这些纳米立方体沉积在具有5的PE层的Au膜的顶部。这样SEM图像用于验证纳米立方体合成的总体质量;然而，这些样品不用于进一步的光学测量作为纳米立方体的密度过高。此外，由于高密度，一些纳米立方体不撒谎这是必不可少形成电浆nanopatch天线结构的表面上。 图3B示出了使用其中已稀释由1/10倍一个纳米立方体溶液纳米立方体的一个样品的SEM图像制成。该样品被用于在那里测量白光的从nanopatch天线的合奏的反射率来确定测量整体等离子体共振。 图3C示出了使用其中已稀释由的1/100倍一个纳米立方体溶液纳米立方体的一个样品的SEM图像制成。该样品被用于散射个体nanopatch天线的测量。使用稀释纳米立方体溶液使得能够个别nanopatch天线通过使用小的针孔是在图像平面空间上隔离。 图4A示出的反射率光谱，用白色光背景，从类似的样品于图3B中 。 如图4B SEM图像中所示的测得的归一化后示出从类似于在示出的样本的单个nanopatch天线的散射光谱在图3C SEM图像。 图4C示出一个nanopatch天线试样的暗场图像（由一个1/10制备分散在金膜与5的PE层0稀释纳米立方体溶液）由尼康D90的数码相机。观察到明亮的红点是由于个别nanopatch天线白色光的散射。少数斑点观察到具有红色以外的颜色，这是具有不同尺寸或更大的纳米颗粒与非立方形状纳米立方体的结果。 图4D示出了两个荧光光谱，一个来自一个单一的nanopatch天线测量（从样品类似于图3C中所示的一个），并从由载玻片具有相同数量的Cy5的PE层和密度的对照样品的另一染料分子。从耦合到所述nanopatch天线Cy5的分子的荧光强度比载玻片上强得多。这是由于增强的激发速率以及染料分子的修饰辐射图案和增加的量子效率。1<html> 2通过用激发光点尺寸的纳米立方体下，将该区域校正每单位面积的背景荧光和正火后，12，我们得到的〜12000从图4D所示的数据的增强因子。 30000 12可能由于使用一个金代替银膜的以前报道的值，增加非辐射损失相比，该增强因子较小。 <img alt="图1" src="/files/ftp_upload/53876/53876fig1.jpg" /> 图1.设备安装的银纳米立方体的合成。（A）设备安装显示与温度控制搅拌加热板的顶部加热浴的照片。 （B）特写含有合成过程中纳米立方体的解决方案圆底烧瓶（RBF）中。该设置位于适当通风良好的通风橱内。TPS://www.jove.com/files/ftp_upload/53876/53876fig1large.jpg"目标="_空白"&gt;点击此处查看该图的放大版本。 <img alt="图2" src="/files/ftp_upload/53876/53876fig2.jpg" /> 图2.图片纳米立方体的解决方案。（A）转移到小管和后2.5小时的合成和（B）后，纳米立方体的解决方案重新悬浮在去离子水。 <a href="https://www.jove.com/files/ftp_upload/53876/53876fig2large.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/53876/53876fig3highres.jpg" width="700" /> 银纳米立方体的 图3 SEM表征。（A）浓缩纳米立方体样品的SEM图像，（B）稀释（1/10）纳米立方体样品，以及（C）稀释（1/100）纳米立方体样品。 <a href="https://www.jove.com/files/ftp_upload/53876/53876fig3highres.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/53876/53876fig4highres.jpg" width="700" /> 图4. nanopatch天线的光学特征。从nanopatch天线（未稀释的纳米立方体的解决方案）的合奏测量（A）标准化反射光谱。从单nanopatch天线（B）散射光谱（1/100稀释纳米立方体的解决方案）。 （C）在白光照明下拍摄的nanopatch天线样品（1/100稀释纳米立方体的解决方案）的暗场图像。每间明亮的红点对应于一个单独的电浆nanopatch天线。从Cy5的染料分子（D）的荧光嵌入DED的相比，从有Cy5染料（黑色虚线）的相同浓度的载玻片。一个nanopatch天线（红色实线） <a href="https://www.jove.com/files/ftp_upload/53876/53876fig4highres.jpg" target="_blank">点击此处查看该图的放大版本。</a>

Watch this Scientific Journal Video about Colloidal Synthesis of Nanopatch Antennas for Applications in Plasmonics and Nanophotonics at JoVE.com

Colloidal Synthesis of Nanopatch Antennas for Applications in Plasmonics and Nanophotonics

一银纳米立方体，并与亚10纳米等离子空白纳米贴片天线的制造胶体合成方案提出。

在等离子体激元和纳米光子学应用Nanopatch天线的合成胶体

We present a method for colloidal synthesis of silver nanocubes and the use of these in combination with a smooth gold film, to fabricate plasmonic ...

colloidal-synthesis-nanopatch-antennas-for-applications-plasmonics

Research

JoVE Journal

Engineering

11.0K 次观看.  Duke University. 一银纳米立方体，并与亚10纳米等离子空白纳米贴片天线的制造胶体合成方案提出。 

视频: Colloidal Synthesis of Nanopatch Antennas for Applications in Plasmonics and Nanophotonics

Hyperpolarized Xenon for NMR and MRI Applications

Nuclear magnetic resonance (NMR) spectroscopy and imaging (MRI) suffer from intrinsic low sensitivity because even strong external magnetic fields of ~10 T generate only a small detectable net-magnetization of the sample at room temperature 1. Hence, most NMR and MRI applications rely on the detection of molecules at relative high concentration (e.g., water for imaging of biological tissue) or require excessive acquisition times. This limits our ability to exploit the very useful molecular specificity of NMR signals for many biochemical and medical applications. However, novel approaches have emerged in the past few years: Manipulation of the detected spin species prior to detection inside the NMR/MRI magnet can dramatically increase the magnetization and therefore allows detection of molecules at much lower concentration 2.
Here, we present a method for polarization of a xenon gas mixture (2-5% Xe, 10% N2, He balance) in a compact setup with a ca. 16000-fold signal enhancement. Modern line-narrowed diode lasers allow efficient polarization 7 and immediate use of gas mixture even if the noble gas is not separated from the other components. The SEOP apparatus is explained and determination of the achieved spin polarization is demonstrated for performance control of the method.
The hyperpolarized gas can be used for void space imaging, including gas flow imaging or diffusion studies at the interfaces with other materials 8,9. Moreover, the Xe NMR signal is extremely sensitive to its molecular environment 6. This enables the option to use it as an NMR/MRI contrast agent when dissolved in aqueous solution with functionalized molecular hosts that temporarily trap the gas 10,11. Direct detection and high-sensitivity indirect detection of such constructs is demonstrated in both spectroscopic and imaging mode.

The production of hyperpolarized xenon by means of spin exchange optical pumping (SEOP) is described. This method yields a ~10000-fold enhancement of the nuclear spin polarization of Xe-129 and has applications in nuclear magnetic resonance spectroscopy and imaging. Examples of gas phase and solution state experiments are given.

超极化氙NMR和MRI的应用

Nuclear magnetic resonance (NMR) spectroscopy and imaging (MRI) suffer from intrinsic low sensitivity because even strong external magnetic fields of ~10 ...

科研

工程学

Solid-state Graft Copolymer Electrolytes for Lithium Battery Applications

Battery safety has been a very important research area over the past decade. Commercially available lithium ion batteries employ low flash point (&lt;80 &deg;C), flammable, and volatile organic electrolytes. These organic based electrolyte systems are viable at ambient temperatures, but require a cooling system to ensure that temperatures do not exceed 80 &deg;C. These cooling systems tend to increase battery costs and can malfunction which can lead to battery malfunction and explosions, thus endangering human life. Increases in petroleum prices lead to a huge demand for safe, electric hybrid vehicles that are more economically viable to operate as oil prices continue to rise. Existing organic based electrolytes used in lithium ion batteries are not applicable to high temperature automotive applications. A safer alternative to organic electrolytes is solid polymer electrolytes. This work will highlight the synthesis for a graft copolymer electrolyte (GCE) poly(oxyethylene) methacrylate (POEM) to a block with a lower glass transition temperature (Tg) poly(oxyethylene) acrylate (POEA). The conduction mechanism has been discussed and it has been demonstrated the relationship between polymer segmental motion and ionic conductivity indeed has a Vogel-Tammann-Fulcher (VTF) dependence. Batteries containing commercially available LP30 organic (LiPF6 in ethylene carbonate (EC):dimethyl carbonate (DMC) at a 1:1 ratio) and GCE were cycled at ambient temperature. It was found that at ambient temperature, the batteries containing GCE showed a greater overpotential when compared to LP30 electrolyte. However at temperatures greater than 60 &deg;C, the GCE cell exhibited much lower overpotential due to fast polymer electrolyte conductivity and nearly the full theoretical specific capacity of 170 mAh/g was accessed.

Lithium ion batteries employ flammable and volatile organic electrolytes that are suitable for ambient temperature applications. A safer alternative to organic electrolytes are solid polymer batteries. Solid polymer batteries operate safely at high temperatures (&gt;120 &deg;C), thus making them applicable to high temperature applications such as deep oil drilling and hybrid electric vehicles. This paper will discuss (a) the polymer synthesis, (b) the polymer conduction mechanism, and (c) provide temperature cycling for both solid polymer and organic electrolytes.

接枝共聚物固态电解质的锂离子电池的应用

Battery safety has been a very important research area over the past decade. Commercially available lithium ion batteries employ low flash point (&lt;80 ...

Synthesis and Operation of Fluorescent-core Microcavities for Refractometric Sensing

This paper discusses fluorescent core microcavity-based sensors that can operate in a microfluidic analysis setup. These structures are based on the formation of a fluorescent quantum-dot (QD) coating on the channel surface of a conventional microcapillary. Silicon QDs are especially attractive for this application, owing in part to their negligible toxicity compared to the II-VI and II-VI compound QDs, which are legislatively controlled substances in many countries. While the ensemble emission spectrum is broad and featureless, an Si-QD film on the channel wall of a capillary features a set of sharp, narrow peaks in the fluorescence spectrum, corresponding to the electromagnetic resonances for light trapped within the film. The peak wavelength of these resonances is sensitive to the external medium, thus permitting the device to function as a refractometric sensor in which the QDs never come into physical contact with the analyte. The experimental methods associated with the fabrication of the fluorescent-core microcapillaries are discussed in detail, as well as the analysis methods. Finally, a comparison is made between these structures and the more widely investigated liquid-core optical ring resonators, in terms of microfluidic sensing capabilities.

Fluorescent-core microcavity sensors employ a high-index quantum-dot coating in the channel of silica microcapillaries. Changes in the refractive index of fluids pumped into the capillary channel cause shifts in the microcavity fluorescence spectrum that can be used to analyze the channel medium.

折光传感荧光芯微腔的合成和操作

This paper discusses  fluorescent core microcavity-based sensors that can operate in a microfluidic  analysis setup. These structures are based on the ...

Three-dimensional Particle Tracking Velocimetry for Turbulence Applications: Case of a Jet Flow

3D-PTV is a quantitative flow measurement technique that aims to track the Lagrangian paths of a set of particles in three dimensions using stereoscopic recording of image sequences. The basic components, features, constraints and optimization tips of a 3D-PTV topology consisting of a high-speed camera with a four-view splitter are described and discussed in this article. The technique is applied to the intermediate flow field (5 &#60;x/d &#60;25) of a circular jet at Re &#8776; 7,000. Lagrangian flow features and turbulence quantities in an Eulerian frame are estimated around ten diameters downstream of the jet origin and at various radial distances from the jet core. Lagrangian properties include trajectory, velocity and acceleration of selected particles as well as curvature of the flow path, which are obtained from the Frenet-Serret equation. Estimation of the 3D velocity and turbulence fields around the jet core axis at a cross-plane located at ten diameters downstream of the jet is compared with literature, and the power spectrum of the large-scale streamwise velocity motions is obtained at various radial distances from the jet core.

A three-dimensional particle tracking velocimetry (3D-PTV) system based on a high-speed camera with a four-view splitter is described here. The technique is applied to a jet flow from a circular pipe in the vicinity of ten diameters downstream at Reynolds number Re &#8776; 7,000.

湍流应用三维粒子跟踪测速:一喷流病例

3D-PTV is a quantitative flow measurement technique that aims to track the Lagrangian paths of a set of particles in three dimensions using stereoscopic ...

Creating Sub-50 Nm Nanofluidic Junctions in PDMS Microfluidic Chip via Self-Assembly Process of Colloidal Particles

Polydimethylsiloxane (PDMS) is the prevailing building material to make microfluidic devices due to its ease of molding and bonding as well as its transparency. Due to the softness of the PDMS material, however, it is challenging to use PDMS for building nanochannels. The channels tend to collapse easily during plasma bonding. In this paper, we present an evaporation-driven self-assembly method of silica colloidal nanoparticles to create nanofluidic junctions with sub-50 nm pores between two microchannels. The pore size as well as the surface charge of the nanofluidic junction is tunable simply by changing the colloidal silica bead size and surface functionalization outside of the assembled microfluidic device in a vial before the self-assembly process. Using the self-assembly of nanoparticles with a bead size of 300 nm, 500 nm, and 900 nm, it was possible to fabricate a porous membrane with a pore size of ~45 nm, ~75 nm and ~135 nm, respectively. Under electrical potential, this nanoporous membrane initiated ion concentration polarization (ICP) acting as a cation-selective membrane to concentrate DNA by ~1,700 times within 15 min. This non-lithographic nanofabrication process opens up a new opportunity to build a tunable nanofluidic junction for the study of nanoscale transport processes of ions and molecules inside a PDMS microfluidic chip.

We propose a simple self-assembly technique of silica colloidal nanoparticles to create a nanofluidic junction between two microchannels in polydimethylsiloxane (PDMS). Using this technique, a nanoporous bead membrane with a pore size down to ~45 nm was built inside a microchannel and applied to electrokinetic preconcentration of DNA samples.

通过胶体粒子自组装过程创建在PDMS微流控芯片分50纳米的纳米流体结

Polydimethylsiloxane (PDMS) is the prevailing building material to make microfluidic devices due to its ease of molding and bonding as well as its ...

Scanning Light Scattering Profiler (SLPS) Based Methodology to Quantitatively Evaluate Forward and Backward Light Scattering from Intraocular Lenses

The scanning light scattering profiler (SLSP) methodology has been developed for the full-angle quantitative evaluation of forward and backward light scattering from intraocular lenses (IOLs) using goniophotometer principles. This protocol describes the SLSP platform and how it employs a 360&#176; rotational photodetector sensor that is scanned around an IOL sample while recording the intensity and location of scattered light as it passes through the IOL medium. The SLSP platform can be used to predict, non-clinically, the propensity for current and novel IOL designs and materials to induce light scatter. Non-clinical evaluation of light scattering properties of IOLs can significantly reduce the number of patient complaints related to unwanted glare, glistening, optical defects, poor image quality, and other phenomena associated with the unintended light scattering. Future studies should be conducted to correlate SLSP data with clinical results to help identify which measured light scatter is most problematic for patients that have undergone cataract surgery subsequent to IOL implantation.

Scanning Light Scattering Profiler SLPS Based Methodology to Quantitatively Evaluate Forward and Backward Light Scattering from Intraocular Lenses

This protocol describes the scanning light scattering profiler (SLSP) that enables the full-angle quantitative evaluation of forward and backward scattering of light from intraocular lenses (IOLs) using goniophotometer principles.

基于扫描光散射分析器（SLPS）的方法来量化评估来自眼内镜的前向和后向光散射

The scanning light scattering profiler (SLSP) methodology has been developed for the full-angle quantitative evaluation of forward and backward light ...

Fabrication of Polymer Microspheres for Optical Resonator and Laser Applications

This paper describes three methods of preparing fluorescent microspheres comprising &#960;-conjugated or non-conjugated polymers: vapor diffusion, interface precipitation, and mini-emulsion. In all methods, well-defined, micrometer-sized spheres are obtained from a self-assembling process in solution. The vapor diffusion method can result in spheres with the highest sphericity and surface smoothness, yet the types of the polymers able to form these spheres are limited. On the other hand, in the mini-emulsion method, microspheres can be made from various types of polymers, even from highly crystalline polymers with coplanar, &#960;-conjugated backbones. The photoluminescent (PL) properties from single isolated microspheres are unusual: the PL is confined inside the spheres, propagates at the circumference of the spheres via the total internal reflection at the polymer/air interface, and self-interferes to show sharp and periodic resonant PL lines. These resonating modes are so-called "whispering gallery modes" (WGMs). This work demonstrates how to measure WGM PL from single isolated spheres using the micro-photoluminescence (&#181;-PL) technique. In this technique, a focused laser beam irradiates a single microsphere, and the luminescence is detected by a spectrometer. A micromanipulation technique is then used to connect the microspheres one by one and to demonstrate the intersphere PL propagation and color conversion from coupled microspheres upon excitation at the perimeter of one sphere and detection of PL from the other microsphere. These techniques, &#181;-PL and micromanipulation, are useful for experiments on micro-optic application using polymer materials.

Protocols for the synthesis of microspheres from polymers, the manipulation of microspheres, and micro-photoluminescence measurements are presented.

用于光学谐振器和激光应用的聚合物微球的制造

This paper describes three methods of preparing fluorescent microspheres comprising &#960;-conjugated or non-conjugated polymers: vapor diffusion, ...

Fabrication of Periodic Gold Nanocup Arrays Using Colloidal Lithography

Within recent years, the field of plasmonics has exploded as researchers have demonstrated exciting applications related to chemical and optical sensing in combination with new nanofabrication techniques. A plasmon is a quantum of charge density oscillation that lends nanoscale metals such as gold and silver unique optical properties. In particular, gold and silver nanoparticles exhibit localized surface plasmon resonances-collective charge density oscillations on the surface of the nanoparticle-in the visible spectrum. Here, we focus on the fabrication of periodic arrays of anisotropic plasmonic nanostructures. These half-shell (or nanocup) structures can exhibit additional unique light-bending and polarization-dependent optical properties that simple isotropic nanostructures cannot. Researchers are interested in the fabrication of periodic arrays of nanocups for a wide variety of applications such as low-cost optical devices, surface-enhanced Raman scattering, and tamper indication. We present a scalable technique based on colloidal lithography in which it is possible to easily fabricate large periodic arrays of nanocups using spin-coating and self-assembled commercially available polymeric nanospheres. Electron microscopy and optical spectroscopy from the visible to near-infrared (near-IR) was performed to confirm successful nanocup fabrication. We conclude with a demonstration of the transfer of nanocups to a flexible, conformal adhesive film.

We demonstrate the fabrication of periodic gold nanocup arrays using colloidal lithographic techniques and discuss the importance of nanoplasmonic films.

用胶体光刻制备周期性金 Nanocup 阵列

Within recent years, the field of plasmonics has exploded as researchers have demonstrated exciting applications related to chemical and optical sensing ...

Fabrication of Superhydrophobic Metal Surfaces for Anti-Icing Applications

Several ways to produce superhydrophobic metal surfaces are presented in this work. Aluminum was chosen as the metal substrate due to its wide use in industry. The wettability of the produced surface was analyzed by bouncing drop experiments and the topography was analyzed by confocal microscopy. In addition, we show various methodologies to measure its durability and anti-icing properties. Superhydrophobic surfaces hold a special texture that must be preserved to keep their water-repellency. To fabricate durable surfaces, we followed two strategies to incorporate a resistant texture. The first strategy is a direct incorporation of roughness to the metal substrate by acid etching. After this surface texturization, the surface energy was decreased by silanization or fluoropolymer deposition. The second strategy is the growth of a ceria layer (after surface texturization) that should enhance the surface hardness and corrosion resistance. The surface energy was decreased with a stearic acid film.
The durability of the superhydrophobic surfaces was examined by a particle impact test, mechanical wear by lateral abrasion, and UV-ozone resistance. The anti-icing properties were explored by studying the ability to repeal subcooled water, freezing delay, and ice adhesion.

We illustrate several methodologies to produce superhydrophobic metal surfaces and to explore their durability and anti-icing properties.

防结冰用超疏水性金属表面的制备

Several ways to produce superhydrophobic metal surfaces are presented in this work. Aluminum was chosen as the metal substrate due to its wide use in ...

A Modular Microfluidic Technology for Systematic Studies of Colloidal Semiconductor Nanocrystals

Colloidal semiconductor nanocrystals, known as quantum dots (QDs), are a rapidly growing class of materials in commercial electronics, such as light emitting diodes (LEDs) and photovoltaics (PVs). Among this material group, inorganic/organic perovskites have demonstrated significant improvement and potential towards high-efficiency, low-cost PV fabrication due to their high charge carrier mobilities and lifetimes. Despite the opportunities for perovskite QDs in large-scale PV and LED applications, the lack of fundamental and comprehensive understanding of their growth pathways has inhibited their adaptation within continuous nanomanufacturing strategies. Traditional flask-based screening approaches are generally expensive, labor-intensive, and imprecise for effectively characterizing the broad parameter space and synthesis variety relevant to colloidal QD reactions. In this work, a fully autonomous microfluidic platform is developed to systematically study the large parameter space associated with the colloidal synthesis of nanocrystals in a continuous flow format. Through the application of a novel translating three-port flow cell and modular reactor extension units, the system may rapidly collect fluorescence and absorption spectra across reactor lengths ranging 3 - 196 cm. The adjustable reactor length not only decouples the residence time from the velocity-dependent mass transfer, it also substantially improves the sampling rates and chemical consumption due to the characterization of 40 unique spectra within a single equilibrated system. Sample rates may reach up to 30,000 unique spectra per day, and the conditions cover 4 orders of magnitude in residence times ranging 100 ms - 17 min. Further applications of this system would substantially improve the rate and precision of the material discovery and screening in future studies. Detailed within this report are the system materials and assembly protocols with a general description of the automated sampling software and offline data processing.

Detailed herein are the operation and assembly protocols of a modular microfluidic screening platform for the systematic characterization of colloidal semiconductor nanocrystal syntheses. Through fully adjustable system arrangements, highly efficient spectra collection may be carried out across 4 orders of magnitude reaction time scales within a mass transfer-controlled sampling space.

胶体半导体纳米晶系统研究的模块化微流控技术

Colloidal semiconductor nanocrystals, known as quantum dots (QDs), are a rapidly growing class of materials in commercial electronics, such as light ...