这项工作的财政支持由能源doe，您好实验室指导研究与发展（LDRD）战略举措计划署提供。我们感谢亨利会议先生和查尔斯Shick先生提供他们的时间和专业知识，我们的实验来帮助我们。

1.纳米材料合成协议<ol><li>制备的 Fe 2原液O 3为25毫米。 注意:所有储备溶液使用去离子水制备的，除非另有说明。 </li><li>取25毫升的锥形瓶中。 </li><li>加入10 mL去离子水，搅拌棒，并把它加热块上。 </li><li>加入100微升的 Fe 2 O 3的储备溶液（25毫摩尔）至该烧瓶中。 </li><li>加热该溶液中，同时搅拌约5分钟。 </li><li>通过将0.1g柠檬酸钠溶解于10ml水制备出10毫升1-％的柠檬酸钠。 </li><li> 1毫升1％的柠檬酸钠溶液添加到含有的 Fe 2 O 3的水溶液25毫升烧瓶中。 </li><li>使溶液到沸腾（100℃）。 </li><li>加入250微升0.01 mol氯金酸。 </li><li>继续加热，在100℃下该溶液10分钟。几分钟（2-3分钟）后，将溶液变成红色/褐色籼婷正在生产的金纳米粒子。 </li><li>除去来自加热块的解决方案，并允许其在室温（约20℃）（1-2小时）冷却。 </li><li>离心4700×g下7分钟纯化样品。 </li><li>从离心样品去除上清。 </li><li>重新分散在去离子水中的离心分离纳米颗粒，最多10毫升</li></ol> 2.纳米表征<ol><li> SEM / EDX表征: <ol><li>放置在铜栅1-2微升离心纳米颗粒并使其干燥1小时。 </li><li>将样品在一个干净的容器，并把它的SEM / EDX用于表征。11,12 </li></ol></li><li> 紫外可见表征: <ol><li>打开紫外可见，并允许它预热10-15分钟。 </li><li>记录的引用去离子水的频谱。 </li><li>地点1毫升纳米颗粒的水溶液中丙烯酸比色皿并记录UV-Vis光谱上的波长λ= 300 - 1000纳米。 </li><li>通过保持最大吸光度较小比〜1.2避免信号的饱和度。如果观察到的最大吸光度越大，由稀释样品或使用较短的路径长度比色皿降低峰值高度。 注:金的表面等离子体带（λ≈525纳米）应该很容易观察到。 </li></ol></li><li> 磁操纵 <ol><li>放置3个毫升丙烯酸甲酯试管磁/等离子纳米结构的红/褐色水样。 </li><li>放置一个商业购买磁铁（〜100高斯）的比色皿的附近。 注:在几分钟之内，所有的磁性/电浆纳米粒子被"附加"到丙烯酸甲酯试管一侧的磁铁放置。溶液从棕色变成无色，表明纳米颗粒保留其磁特性的Au沉积在的 Fe 2即使</sub&gt; O 3面。 </li></ol></li><li> 电感耦合等离子体质谱仪（ICP-MS）分析13 <ol><li>使用纳米颗粒溶液的水溶液样品中的这种分析。 </li><li>消化纯化的纳米颗粒样品中的硝酸将它们转换到通过在管与10毫升的2％的硝酸的终体积转印所有样品质量分析的实验之前，离子形式。允许30分钟消化发生。 </li><li>创建与感兴趣的分析物（例如，金，铁）的已知浓度的校准曲线。 </li><li>用含有10ppb的铑和在与内标溶液穗的样本分析中，根据制造商的说明ICP-MS的半定量方式。这种技术蕴涵A NIST溯源多元素标准的分析（10 ppb的在和100ppb的锂，锰，铁，钴，锶，镉，铋，和U）。 </li><li>比较确定的强度与该intensiti标准对于其他样品ES产生近似浓度选中的元素。考虑到等离子体和仪器漂移，所有的样品应当具有最低10ppb的浓度为在该加入到所有样品。 </li><li>确定为通过以下步骤准备好的解决方案，利益分析的元素浓度: <ol><li>执行多元素标准的初始校准验证样品（10 ppb的在75 ppb的锂，镁，铁，钴，锶，镉，铋，和U）。 </li><li>执行的去离子水初始校准空白。 </li><li>感兴趣两个采样进行ICP-MS分析。 </li><li>继续执行校准验证样品（10 ppb的在75 ppb的锂，镁，铁，钴，锶，镉，铋，和U）的多元素的标准。 </li><li>不断的去离子水校准空白。 注意:根据供应商的说明，在ICP-MS测量具有20％的不确定性。纳米材料的实验室工作下进行自动对焦UME罩。如果罩格高于下巴水平PPE（实验服，围裙，瘦万丁腈手套的偶然接触和护目镜），以及面罩应该被使用。最小PPE与纳米材料工作时必需的;一次性白大褂，对于偶然接触和防护眼镜带侧护板薄万丁腈手套将在实验室纳米材料处理时佩戴。纳米材料浪费轴承不得放在普通垃圾或血本无归。 </li></ol></li></ol></li></ol> 3.激光加热实验<ol><li>接通激光电源和平衡。 注意:在这个实验中（λ= 532纳米）中所用的激光波长被选择为所述LSPR吸收峰尽可能匹配。然而，光热效果可以使用与纳米粒子的吸收重叠的任何波长进行诱导。共振照亮时的加热效率仅仅是更大的。 </li><li>平衡的窗户，使他们D档O不可阻挡的激光路径或阻挡红外线（IR）热电偶。红外热电偶都是非接触式温度探测器和必须的视线测量清晰线的表面上。 图1示出实验装置的示意图。 </li><li>从IR热电偶取下防护罩。 </li><li>打开数据采集软件程序并运行，命名测量，"热身"。定制软件程序收集的平衡和热电偶的电阻值作为时间的函数，并且在程序运行时，记录这些值到一个数据文件。 </li><li>运行测量至少20分钟，以使系统预热。 </li><li>当系统正在预热，吹打所需溶液适量（3毫升）中成甲基丙烯酸酯反应杯准备的样品。这里使用的量3毫升为标准比色皿的解决方案，和1ml用于半微量比色杯。 </li><li>调整激光功率到最低SETT荷兰国际集团的产生隐约可见的光束，它是1.5 A为这里使用的激光系统。检查以确保激光束光斑通畅并保持在红外热电偶的焦点。 </li><li>放置在平衡臂的样本，使得样本池的侧垂直于热电偶和激光束光斑的IR测定光束照射该溶液的中心。 </li><li>降低激光功率直到光束不再可见，但不要关闭电源。 </li><li> 20分钟后，热身完毕。停止测量程序，然后退出软件。 </li><li>重新归零的平衡。打开数据采集软件，单击运行，然后创建数据文件的名称。该实验将命名文件并点击后运行"保存"。确切的实验程序将取决于所需的信息，但这里提供的模型程序。 <ol><li>启动数据收集。 120秒后，打开了第lASER功率所需的设置（1.2 W为这些实验中，其中当聚焦成〜20μm的光斑以〜3.8×10 5瓦/厘米2对应 ）。收集数据，另外1,000秒，然后调整激光功率，以最小设置和关闭激光电源。继续暂停测量之前收集另一个1,000秒的数据。 </li></ol></li><li>实验程序完成后，将退出程序，关闭所有设备，并重新覆盖所有设备。保存实验数据以ASCII格式，并进一步处理和使用其他软件进行分析。 </li></ol>

<ol>
	<li>Barber, D., Freestone, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+investigation+of+the+origin+of+the+colour+of+the+Lycurgus+Cup+by+analytical+transmission+electron+microscopy.">An investigation of the origin of the colour of the Lycurgus Cup by analytical transmission electron microscopy.</a> Archaeometry. 32 (1), 33-45 (1990).</li><li>Ozbay, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Plasmonics:+merging+photonics+and+electronics+at+nanoscale+dimensions.">Plasmonics: merging photonics and electronics at nanoscale dimensions.</a> Science. 311 (5758), 189-193 (2006).</li><li>Murphy, C. J., 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=Anisotropic+metal+nanoparticles:+synthesis,+assembly,+and+optical+applications.">Anisotropic metal nanoparticles: synthesis, assembly, and optical applications.</a> J. Phys. Chem. B. 109 (29), 13857-13870 (2005).</li><li>Luo, Y. L., Shiao, Y. S., Huang, Y. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Release+of+photoactivatable+drugs+from+plasmonic+nanoparticles+for+targeted+cancer+therapy.">Release of photoactivatable drugs from plasmonic nanoparticles for targeted cancer therapy.</a> ACS Nano. 5 (10), 7796-7804 (2011).</li><li>Murph, S. E. H., 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=Manganese-gold+nanoparticles+as+an+MRI+positive+contrast+agent+in+mesenchymal+stem+cell+labeling.">Manganese-gold nanoparticles as an MRI positive contrast agent in mesenchymal stem cell labeling.</a> J. Nanopart. Res. 14 (4), 1-13 (2012).</li><li>Maier, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Plasmonics: fundamentals and applications: fundamentals and applications. , (2007).</li><li>Bigall, N. C., Parak, W. J., Dorfs, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fluorescent+magnetic+and+plasmonic-Hybrid+multifunctional+colloidal+nano+objects.">Fluorescent magnetic and plasmonic-Hybrid multifunctional colloidal nano objects.</a> Nano Today. 7 (4), 282-296 (2012).</li><li>Larson, T. A., Bankson, J., Aaron, J., Sokolov, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hybrid+plasmonic+magnetic+nanoparticles+as+molecular+specific+agents+for+MRI/optical+imaging+and+photothermal+therapy+of+cancer+cells.">Hybrid plasmonic magnetic nanoparticles as molecular specific agents for MRI/optical imaging and photothermal therapy of cancer cells.</a> Nanotechnology. 18 (32), 325101 (2007).</li><li>Hung, W. H., Aykol, M., Valley, D., Hou, W., Cronin, S. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Plasmon+resonant+enhancement+of+carbon+monoxide+catalysis.">Plasmon resonant enhancement of carbon monoxide catalysis.</a> Nano Lett. 10 (4), 1314-1318 (2010).</li><li>Neumann, O., 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=Solar+vapor+generation+enabled+by+nanoparticles.">Solar vapor generation enabled by nanoparticles.</a> Acs Nano. 7 (1), 42-49 (2012).</li><li>Szirmae, A., Fisher, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Techniques of Electron Microscopy, Diffraction, and Microprobe Analysis. 372, (1963).</li><li>Goldstein, J., 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=.">.</a> Scanning electron microscopy and X-ray microanalysis: a text for biologists, materials scientists, and geologists. , (2012).</li><li>Kennedy, J. F., Xu, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Practical+guide+to+ICP-MS,+Robert+Thomas.+Marcel+Dekker,+INC,+New+York,+USA+(2004).">Practical guide to ICP-MS, Robert Thomas. Marcel Dekker, INC, New York, USA (2004).</a> Carbohydr. Polym. 62 (4), 393 (2005).</li><li>Georgakilas, V., 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=Decorating+carbon+nanotubes+with+metal+or+semiconductor+nanoparticles.">Decorating carbon nanotubes with metal or semiconductor nanoparticles.</a> J. Mater. Chem. 17 (26), 2679-2694 (2007).</li><li>Murph, S. E. H., 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=Tuning+of+size+and+shape+of+Au-Pt+nanocatalysts+for+direct+methanol+fuel+cells.">Tuning of size and shape of Au-Pt nanocatalysts for direct methanol fuel cells.</a> J. Nanopart. Res. 13 (12), 6347-6364 (2011).</li><li>Unrine, J. 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=Evidence+for+bioavailability+of+Au+nanoparticles+from+soil+and+biodistribution+within+earthworms+(Eisenia+fetida).">Evidence for bioavailability of Au nanoparticles from soil and biodistribution within earthworms (Eisenia fetida).</a> Environ. Sci. Technol. 44 (21), 8308-8313 (2010).</li><li>Hunyadi Murph, S. E., 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=.">.</a> ACS Symp. Ser. , 127-163 (2011).</li><li>Murph, S., Murphy, C. J., Leach, A., Gall, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Possible+Oriented+Attachment+Growth+Mechanism+for+Silver+Nanowire+Formation.">A Possible Oriented Attachment Growth Mechanism for Silver Nanowire Formation.</a> Cryst Growth Des. , (2015).</li><li>Hunyadi Murph, S. E., Heroux, K., Turick, C., Thomas, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Applications of Nanomaterials. Vol. 4 Nanomaterials and Nanostructures, (2012).</li><li>Murphy, C. J., 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=Chemical+sensing+and+imaging+with+metallic+nanorods.">Chemical sensing and imaging with metallic nanorods.</a> Chem. Comm. (5), 544-557 (2008).</li><li>Shanmukh, S., 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=Rapid+and+sensitive+detection+of+respiratory+virus+molecular+signatures+using+a+silver+nanorod+array+SERS+substrate.">Rapid and sensitive detection of respiratory virus molecular signatures using a silver nanorod array SERS substrate.</a> Nano Lett. 6 (11), 2630-2636 (2006).</li><li>Jaque, D., Vetrone, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Luminescence+nanothermometry.">Luminescence nanothermometry.</a> Nanoscale. 4 (15), 4301-4326 (2012).</li><li>Ebrahimi, S., Akhlaghi, Y., Kompany-Zareh, M., Rinnan, &. #. 1. 9. 7. ;. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nucleic+acid+based+fluorescent+nanothermometers.">Nucleic acid based fluorescent nanothermometers.</a> ACS Nano. 8 (10), 10372-10382 (2014).</li><li>Dias, J. T., 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=DNA+as+a+molecular+local+thermal+probe+for+the+analysis+of+magnetic+hyperthermia.">DNA as a molecular local thermal probe for the analysis of magnetic hyperthermia.</a> Angew. Chem. 125 (44), 11740-11743 (2013).</li></ol>

作者什么都没有透露。

热疗研究使用光可调谐的金纳米粒子是一个有吸引力的选择，因为它利用了调整，以在VIS-NIR区域的强烈吸收光的金纳米粒子的表面等离子体加热。这里所描述的等离子加热研究是通过使用实验室制备和可商购的氧化铁 - 金混合纳米材料检查。之一的用于制造胶体金nanospherical颗粒最广泛使用的方法涉及的氯金酸（氯金酸4）还原成中性金Au（0）通过减少剂，如柠檬酸钠，硼氢化钠等15,16的合成对氧化铁纳米颗粒的纳米金是直接的。人们可以很容易地控制在Au金属的大小，形状，和装载通过改变实验参数，例如，反应物浓度，还原剂，表面活性剂等17这种方法产生过度的Au nanoparticl良好控制Ë尺寸均匀的纳米装上的 Fe 2 O 3。其它贵金属也可以通过该过程，包括银，铂，和钯制备。18此过程的一个显着优点是，该反应过程可以在空气中或水中进行，并且在原则上，是适合于扩大。使用商业纳米材料和/或可伸缩的湿化学过程，因为这些材料是容易超过常规合成材料和程序可用，更经济的是理想的大规模处理应用或生物应用。这些金属纳米结构的表面修饰是在科学界的兴趣也。若干有机（表面活性剂，双官能硫醇，聚合物，氨基酸，蛋白质，DNA）和无机材料（二氧化硅，其它金属， 金属氧化物等）19可以进一步加载或官能化到这些表面以创建具有各种纳米复合材料设计，几何，成分和多功能能力，为生物靶向，药物传递，传感，成像，环境应用等 。 此外，这里所描述的光热技术非常适合以表征不同材料的电浆属性，散装温度和质量测量相对容易使用容易获得的设备来执行。样品制备和测量的易用性是比其他等离子技术/应用具有明显的优势。例如，技术如表面增强拉曼光谱和LSPR感测是在制备衬底和目标的，20,21这使得可重复性和跨样本更具挑战性的比较高度敏感。一个可能的缺点与上述光热测量是该温度是在批量规模，而不是在这里热量被转导的纳米颗粒的表面上测量的。有热metry技术，可以提供这样的局部温度信息，22-24，但这些都需要更复杂的样品制备，使他们更有挑战性的实施。最后，这里所描述的测量，可以很容易地与其它技术 （如光催化降解）9相结合，以评估不同的进程光热效应。 总之，我们已经描述了杂交体的 Fe 2 O 3的-Au纳米颗粒溶液和它们的光热表征的合成。即使有Au的20×较小浓度，这些的 Fe 2 O 3的-Au纳米颗粒能够尽可能有效光热热水溶液作为金纳米粒子，表明混合物料的优点。此外，该混合结构保留这两种材料的特性，创建具有磁性和电浆属性的多功能结构。这样的结构是用于生物医学应用有兴趣，8但许多其他用途，可以预见的。

与他们在古老的分色玻璃的使用开始，1金纳米粒子（纳米金）往往促成了新技术的发展。2,3更现代的这些技术的例子包括隐形装置和颗粒既可以检测和治疗癌症。4,5金纳米粒子具有许多显着的特点，但其中最引人注目的是局部表面等离子体共振（LSPRs），电子当入射电磁辐射共振驱 ​​动器免费而发生转化为集体振荡，产生强烈的和高度受限电磁场的存在。6一个有趣的方面LSPRs的是，它们是可调谐的。也就是说，共振能量可以通过修改金纳米粒子的形状和大小，或通过改变周围环境的折射率进行调整。金纳米粒子的另一个属性，以及金在一般情况下，是它们比较昂贵。虽然这可能令金价从更具吸引力豪华的观点来看，对技术的应用，这是一个缺点，并可能是一个障碍一般用途。对于此问题的两种可能的解决方案正在寻找表现出类似的性质如金较便宜的替代材料，或寻找一种方法来金与另一种材料组合以创建具有类似性质的，但较少量的贵金属的复合材料。后者的解决方案是可能更有趣，因为它允许创建具有两种或更多种材料的物理化学性质的多功能混合纳米结构的可能性。7 氧化铁，铁2 O 3是对于这样的混合物中的一种成分的优异的候选者，因为它是广泛使用的，价格低廉，且无毒。此外，磁赤铁矿相的γ 的 Fe 2 O 3，是铁磁和赤铁矿相，的α-Fe 2 O 3，是弱铁磁性的。因此，该组合金为Fe 2 O 3可能得到表现出等离子性质，并与外部磁场相互作用，但是显著比纯金更便宜的纳米颗粒。这种混合纳米结构可以发现，有趣的现实世界的应用。例如，铁2 O 3 -Au纳米颗粒被证明为癌症的诊断和治疗通过磁共振成像和光热治疗8在这种情况下是有用的， 的 Fe 2 O 3用作MRI造影剂，而金部局部地转换入射光光热透LSPR过程中吸收的电磁能量耗散。此外，铁2 O 3 -Au纳米颗粒已经证明CO的可见光照明催化转化成CO 2的电浆增强，并且也可用于光热太阳能转换这样的结构。9,10- 氏的报告描述的Fe 2 O 3纳米-Au使用一个简单的湿化学方法合成。混合结构由饰有金纳米颗粒越小一个的 Fe 2 O 3的核心。重要的是，所得到的 Fe 2 O 3的-Au颗粒保留构成材料，它创建了一个多功能颗粒，可能是用于各种应用中有用的两磁性和电浆特性。为了说明这些混合纳米颗粒的等离子体激元的应用程序，利用激光加热系统的纳米颗粒的光热表征还描述。光热测量表明，该混合的 Fe 2 O 3的-Au纳米颗粒能够作为有效地加热水溶液作为纯粹的AuNPs，即使有贵金属的显著较小浓度。这些结果证实使用复合材料或混合材料，以降低成本，实现更大functionalit的方法年。

<table><tbody><tr><td>&lt;strong&gt;Gold(III) chloride trihydrate&amp;nbsp;&lt;/strong&gt;</td><td>Sigma-Aldrich</td><td>520918&amp;nbsp;</td><td>&amp;ge;99.9% trace metals basis</td></tr><tr><td>&lt;strong&gt;Iron(III) oxide&lt;/strong&gt;</td><td>Sigma-Aldrich</td><td>544884</td><td>nanopowder, &amp;lt;50&amp;nbsp;nm particle size (BET)</td></tr><tr><td>Sodium citrate tribasic dihydrate</td><td>Sigma-Aldrich</td><td>S4641</td><td>ACS reagent, &amp;ge;99.0%&amp;nbsp;</td></tr><tr><td>SEM</td><td>Hitachi&amp;nbsp;</td><td>S8200</td><td></td></tr><tr><td>TEM</td><td>Hitachi&amp;nbsp;</td><td>H95000</td><td></td></tr><tr><td>EDX</td><td>Oxford Instruments&amp;nbsp;</td><td>SDD - X-Max</td><td></td></tr><tr><td>DLS</td><td>Brookhaven Instruments</td><td>NanoBrook Omni</td><td></td></tr><tr><td>ICP-MS</td><td>Agilent&amp;nbsp;</td><td>7500s</td><td></td></tr><tr><td>UV-Vis-NIR spectrometer</td><td>Tec5 MultiSpec</td><td></td><td></td></tr><tr><td>Laser, &amp;lambda; = 532 nm&amp;nbsp;</td><td>Del Mar Photonics</td><td>DMPV-532-1</td><td></td></tr><tr><td>Microgram Balance</td><td>Mettler Toledo&amp;nbsp;</td><td>XP205</td><td></td></tr><tr><td>Infrared Thermocouples</td><td>Omega Engineering</td><td>OS801-HT</td><td></td></tr></tbody></table>

multifunctional hybrid fe2o3-au nanoparticles for efficient plasmonic heating

之一的用于制造胶体金nanospherical颗粒最广泛使用的方法涉及的氯金酸（氯金酸4）中性金Au的还原（0）通过还原剂，诸如柠檬酸钠或硼氢化钠。该方法的扩展来装饰氧化铁或类似的纳米颗粒具有金纳米颗粒创建多功能混合的 Fe 2 O 3的-Au纳米颗粒是简单的。这种方法产生了金纳米颗粒的尺寸和装上的 Fe 2 O 3相当不错的控制。此外，在Au金属的大小，形状，和装载可以容易地通过改变实验参数（例如，反应物浓度，还原剂，表面活性剂等）调谐。此过程的一个优点是，反应可以在空气中或水中进行，并且在原则上，是适合于扩大。使用这样的光学可调的铁2 O 3 -Au纳米颗粒hypertherMIA的研究是一个有吸引力的选择，因为它利用了调整，以在VIS-NIR区域的强烈吸收光的金纳米粒子的表面等离子体加热。除了它的电浆的效果，纳米级金提供了有趣的化学和催化独特的表面。铁2 O 3的材料，由于其磁性能提供额外的功能。例如，外部磁场可用于催化试验后2 O 3 -Au颗粒收集和回收的混合动力车的Fe，或者可替换地，磁性的 Fe 2 O 3可用于通过磁热感应热疗研究。作为时间的函数用红外热电偶和平衡，分别在本报告中所述的光热实验测量本体温度变化和纳米颗粒溶液的质量损失。样品制备的便利性和使用的容易获得的设备是这种技术的显着的优点。一个需要注意的是日在这些光热测量评估本体溶液温度，而非在其中的热量被转导的纳米颗粒的表面和温度可能会更高。

材料组合物是混合材料的一个重要的考虑因素。能量色散X射线分析（EDX）和电感耦合等离子体质谱仪（ICP-MS）可以提供此信息。 EDX分析提供半定量数据（图2），而ICP-MS提供了关于感兴趣的元素准确的定量信息。据发现，该混合的 Fe 2 O 3的-Au纳米颗粒具有ρFe= 150 ppb的和ρAu= 49 ppb数量的Fe和Au的浓度。相比较而言，纯金纳米粒子，它被​​用作光热加热的控制，有ρAu= 1100 ppb的高得多的金浓度。 SEM分析揭示的 Fe 2 O 3 -Au纳米颗粒的形态（ 图3），示出圆形，不规则颗粒的聚集体即出现官能较小，明亮，圆润的纳米粒子。较大的纳米颗粒被确定为的 Fe 2 O 3，而较小的，更明亮的纳米颗粒被鉴定为金。这种类型的形态通常称为"装饰"纳米颗粒。14在这种情况下，支撑颗粒的表面， 的 Fe 2 O 3，是装饰用较小的，孤立的Au纳米颗粒。纳米颗粒的统计分析表明， 的 Fe 2 O 3纳米颗粒具有D的平均直径= 40±10纳米。所述官能化金纳米粒子具有更广泛的范围内的尺寸，其中d = 20±20纳米。动态光散射（DLS）测量可量化的聚集行为，可以发现，混合的 Fe 2 O 3的-Au纳米颗粒具有DH = 243毫微米与DH = 61纳米（13％）的人口箱的平均流体动力学半径和DH = 310纳米（87％）。此外，ζ电位是发现于ζ= -16毫伏，这可能有助于限制聚集行为。 的杂交体的UV-VIS-NIR光谱的 Fe 2 O 3的-Au颗粒示于图4A。一个明显的吸收峰是在波长λ≈520纳米观察到的，并且是由于在Au纳米颗粒官能化的 Fe 2 O 3的LSPR模式。该LSPR的波长与具有类似形态的AuNPs文献值一致。11,12的混合结构的电浆行为是由于上的 Fe 2 O 3的支撑金纳米粒子的形成。这可以通过原位紫外可见光谱直接观察到。 图4B示出在反应过程中的不同时间的反应物溶液的紫外可见吸收光谱。最初，有归因于的 Fe 2 O 3纳米颗粒分散在溶液中的一些轻微可见光吸光度。随着反应的进行，该ABSO<html> rbance增加，并且在1.5分钟，峰值开始形成，从而可更好地定义为反应的推移。从LSPR吸光度该峰的结果和对应于金纳米粒子和其沉积中的Fe 2 O 3的支撑表面上的形成。所述的 Fe 2 O 3 -Au纳米颗粒的磁特性可容易地通过操纵与外部磁场变化。最初， 的 Fe 2 O 3的-Au溶液具有褐色（图5B）。然而，将所述溶液中的外部磁场后，将溶液逐渐作为磁混合纳米粒子的全部由场（图5C）收集翻转数分钟清楚。磁收集是可逆的，和多官能纳米粒子可通过搅拌溶液再分散， 如图5D 和 5E。 1"&gt;光热加热测量显示在图6A中 ，其绘制在辐照溶液的整体温度变化，ΔT，作为用于混合的 Fe 2 O 3 -Au纳米颗粒，金纳米颗粒，和纯净的去离子水（DI 的 H 2与时间的函数O）。中Fe 2 O 3 -Au和金纳米粒子表现出几乎相同的温度曲线，温度超过40℃上升。显然，这两种类型的纳米颗粒能够转导光转化为热能非常有效的等离子吸光度，但中Fe 2 O 3的 -Au用Au的相当低的浓度为此，如上所讨论的。在另一方面，在去离子水中2 O实验示出了在没有温度变化，这表明在该纳米颗粒溶液的温度上升是完全由于吸收了电磁能量在纳米颗粒中的耗散。ΔT 图 6A描述了散装变化temperatur即，和温度在照射区域和纳米颗粒表面附近可以是高得多。13中的溶液，ΔM，即产生于蒸汽发生的质量的变化是这些较高的温度下的一个指标。 图6B绘出ΔM与时间的关系混合的Fe 2 O 3纳米-Au和DI H 2 O. ΔM为纳米颗粒溶液比背景蒸发速度大得多，表明足够高的表面温度在显著速率以产生蒸汽。 <img alt="图1" src="/files/ftp_upload/53598/53598fig1.jpg" /> 图1的激光加热的设置的示意图，一个小杯放置在一微克规模和照明用激光束从上方。两个红外热电偶测量反应杯和环境的温度，分别为。所有的测量是同步的，并记录在一个数据collecti关于程序。 <a href="https://www.jove.com/files/ftp_upload/53598/53598fig1large.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/53598/53598fig2.jpg" /> 混合的 图2 代表EDX谱的 Fe 2 O 3的-Au纳米颗粒。横轴对应的能量，纵轴与计数的数目对应。峰被标有对应的元素。 <a href="https://www.jove.com/files/ftp_upload/53598/53598fig2large.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/53598/53598fig3.jpg" /> 图3. 混合的SEM图像的Fe 2 O 3纳米-Au该 LARG<html>呃，较暗区域为Fe 2 O 3粒子 ，装饰有亮较小的金纳米粒子。 <a href="https://www.jove.com/files/ftp_upload/53598/53598fig3large.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/53598/53598fig4.jpg" width="400" /> 图4. 光学特性:（A）紫外吸收混合的光谱的 Fe 2 O 3 -Au纳米颗粒，示出的 Fe 2 O 3的宽可见光吸收率和归因于邻近530nm的金纳米粒子的电浆峰。 （B）在反应过程中的不同时间的反应物溶液，示出了在溶液中和在的Fe 2 O 3纳米颗粒从金纳米粒子的形成所产生的LSPR吸光度的紫外可见吸收光谱。.COM /文件/ ftp_upload / 53598 / 53598fig4large.jpg"目标="_空白"&gt;点击此处查看该图的放大版本。 <img alt="图5" src="/files/ftp_upload/53598/53598fig5.jpg" /> 图5. 磁性能的Au-的Fe 2 O 3纳米颗粒的照片。分散在水溶液 （A）; （B）磁性操纵（时间= 0秒）; （℃）磁性操纵（时间= 2分钟）; （D）磁铁取出; （E）的Au-铁磁性如下操作2 O 3纳米粒子，这表明它们可以轻松地重新分散在水溶液中。 <a href="https://www.jove.com/files/ftp_upload/53598/53598fig5large.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/53598/53598fig6.jpg"/&gt; 图6. 光热实验。图解表示溶液的温度，ΔT，和（B）的质量损失，ΔM的（A）的变化，作为时间的函数。根据激光照射，纳米粒子（黑色和红色曲线）产生相当大的ΔT和ΔM值那些比发生纯DI H 2Ø在相同条件下（蓝色曲线）显著更大。 <a href="https://www.jove.com/files/ftp_upload/53598/53598fig6large.jpg" target="_blank">请点击此处查看该图的放大版本。</a>

Watch this Scientific Journal Video about Multifunctional Hybrid Fe2O3-Au Nanoparticles for Efficient Plasmonic Heating at JoVE.com

Multifunctional Hybrid Fe2O3-Au Nanoparticles for Efficient Plasmonic Heating

We describe the synthesis and properties of multifunctional Fe2O3-Au nanoparticles produced by a wet chemical approach and investigate their photothermal properties using laser irradiation. The composite Fe2O3-Au nanoparticles retain the properties of both materials, creating a multifunctional structure with excellent magnetic and plasmonic properties.

多功能混合铁<sub&gt; 2</sub&gt; 0<sub&gt; 3</sub&gt; -Au纳米粒子高效的电浆暖气

One of the most widely used methods for manufacturing colloidal gold nanospherical particles involves the reduction of chloroauric acid (HAuCl4) to ...

multifunctional-hybrid-fe2o3-au-nanoparticles-for-efficient-plasmonic

Research

JoVE Journal

Engineering

Multifunctional Hybrid Fe2O3-Au Nanoparticles for Efficient Plasmonic Heating

13.6K 次观看.  Savannah River National Laboratory. We describe the synthesis and properties of multifunctional Fe2O3-Au nanoparticles produced by a wet chemical approach and investigate their photothermal properties using laser irradiation. The composite Fe2O3-Au nanoparticles retain the properties of both materials, creating a multifunctional structure with excellent magnetic and plasmonic properties.

视频: Multifunctional Hybrid Fe2O3-Au Nanoparticles for Efficient Plasmonic Heating

Design, Fabrication, and Experimental Characterization of Plasmonic Photoconductive Terahertz Emitters

In this video article we present a detailed demonstration of a highly efficient method for generating terahertz waves. Our technique is based on photoconduction, which has been one of the most commonly used techniques for terahertz generation 1-8. Terahertz generation in a photoconductive emitter is achieved by pumping an ultrafast photoconductor with a pulsed or heterodyned laser illumination. The induced photocurrent, which follows the envelope of the pump laser, is routed to a terahertz radiating antenna connected to the photoconductor contact electrodes to generate terahertz radiation. Although the quantum efficiency of a photoconductive emitter can theoretically reach 100%, the relatively long transport path lengths of photo-generated carriers to the contact electrodes of conventional photoconductors have severely limited their quantum efficiency. Additionally, the carrier screening effect and thermal breakdown strictly limit the maximum output power of conventional photoconductive terahertz sources. To address the quantum efficiency limitations of conventional photoconductive terahertz emitters, we have developed a new photoconductive emitter concept which incorporates a plasmonic contact electrode configuration to offer high quantum-efficiency and ultrafast operation simultaneously. By using nano-scale plasmonic contact electrodes, we significantly reduce the average photo-generated carrier transport path to photoconductor contact electrodes compared to conventional photoconductors 9. Our method also allows increasing photoconductor active area without a considerable increase in the capacitive loading to the antenna, boosting the maximum terahertz radiation power by preventing the carrier screening effect and thermal breakdown at high optical pump powers. By incorporating plasmonic contact electrodes, we demonstrate enhancing the optical-to-terahertz power conversion efficiency of a conventional photoconductive terahertz emitter by a factor of 50 10.

We describe methods for the design, fabrication, and experimental characterization of plasmonic photoconductive emitters, which offer two orders of magnitude higher terahertz power levels compared to conventional photoconductive emitters.

电浆光电导太赫兹发射器的设计，制造和实验表征

In this video article we present a detailed demonstration of a highly efficient method for generating terahertz waves. Our technique is based on ...

科研

工程学

Utilization of Plasmonic and Photonic Crystal Nanostructures for Enhanced Micro- and Nanoparticle Manipulation

A method to manipulate the position and orientation of submicron particles nondestructively would be an incredibly useful tool for basic biological research. Perhaps the most widely used physical force to achieve noninvasive manipulation of small particles has been dielectrophoresis(DEP).1 However, DEP on its own lacks the versatility and precision that are desired when manipulating cells since it is traditionally done with stationary electrodes. Optical tweezers, which utilize a three dimensional electromagnetic field gradient to exert forces on small particles, achieve this desired versatility and precision.2 However, a major drawback of this approach is the high radiation intensity required to achieve the necessary force to trap a particle which can damage biological samples.3 A solution that allows trapping and sorting with lower optical intensities are optoelectronic tweezers (OET) but OET's have limitations with fine manipulation of small particles; being DEP-based technology also puts constraint on the property of the solution.4,5
This video article will describe two methods that decrease the intensity of the radiation needed for optical manipulation of living cells and also describe a method for orientation control. The first method is plasmonic tweezers which use a random gold nanoparticle (AuNP) array as a substrate for the sample as shown in Figure 1. The AuNP array converts the incident photons into localized surface plasmons (LSP) which consist of resonant dipole moments that radiate and generate a patterned radiation field with a large gradient in the cell solution. Initial work on surface plasmon enhanced trapping by Righini et al and our own modeling have shown the fields generated by the plasmonic substrate reduce the initial intensity required by enhancing the gradient field that traps the particle.6,7,8 The plasmonic approach allows for fine orientation control of ellipsoidal particles and cells with low optical intensities because of more efficient optical energy conversion into mechanical energy and a dipole-dependent radiation field. These fields are shown in figure 2 and the low trapping intensities are detailed in figures 4 and 5. The main problems with plasmonic tweezers are that the LSP's generate a considerable amount of heat and the trapping is only two dimensional. This heat generates convective flows and thermophoresis which can be powerful enough to expel submicron particles from the trap.9,10 The second approach that we will describe is utilizing periodic dielectric nanostructures to scatter incident light very efficiently into diffraction modes, as shown in figure 6.11 Ideally, one would make this structure out of a dielectric material to avoid the same heating problems experienced with the plasmonic tweezers but in our approach an aluminum-coated diffraction grating is used as a one-dimensional periodic dielectric nanostructure. Although it is not a semiconductor, it did not experience significant heating and effectively trapped small particles with low trapping intensities, as shown in figure 7. Alignment of particles with the grating substrate conceptually validates the proposition that a 2-D photonic crystal could allow precise rotation of non-spherical micron sized particles.10 The efficiencies of these optical traps are increased due to the enhanced fields produced by the nanostructures described in this paper.

Plasmonic tweezers and photonic crystal nanostructures are shown to produce useful enhancements in the efficiency and orientation control of optically trapping micro- and nano-particles.

为增强微型和纳米操纵利用电浆和光子晶体纳米结构

A method to manipulate the position and orientation of submicron particles nondestructively would be an incredibly useful tool for basic biological ...

生物工程

Synthesis of Immunotargeted Magneto-plasmonic Nanoclusters

Magnetic and plasmonic properties combined in a single nanoparticle provide a synergy that is advantageous in a number of biomedical applications including contrast enhancement in novel magnetomotive imaging modalities, simultaneous capture&#160;and detection of circulating tumor cells (CTCs),&#160;and multimodal molecular imaging combined with photothermal therapy of cancer cells. These applications have stimulated significant interest in development of protocols for synthesis of magneto-plasmonic nanoparticles with optical absorbance in the near-infrared (NIR) region and a strong magnetic moment. Here, we present a novel protocol for synthesis of such hybrid nanoparticles that is based on an oil-in-water microemulsion method. The unique feature of the protocol described herein is synthesis of magneto-plasmonic nanoparticles of various sizes from primary blocks which also have magneto-plasmonic characteristics. This approach yields nanoparticles with a high density of magnetic and plasmonic functionalities which are uniformly distributed throughout the nanoparticle volume. The hybrid nanoparticles can be easily functionalized by attaching antibodies through the Fc moiety leaving the Fab portion that is responsible for antigen binding available for targeting.

Here, we describe a protocol for synthesis of magneto-plasmonic nanoparticles with a strong magnetic moment and a strong near-infrared (NIR) absorbance. The protocol also includes antibody conjugation to the nanoparticles through the Fc moiety for various biomedical applications which require molecular specific targeting.

Immunotargeted的合成磁等离子团簇

Magnetic and plasmonic properties combined in a single nanoparticle provide a synergy that is advantageous in a number of biomedical applications ...

化学

Synthesis, Characterization, and Functionalization of Hybrid Au/CdS and Au/ZnS Core/Shell Nanoparticles

Plasmonic nanoparticles are an attractive material for light harvesting applications due to their easily modified surface, high surface area and large extinction coefficients which can be tuned across the visible spectrum. Research into the plasmonic enhancement of optical transitions has become popular, due to the possibility of altering and in some cases improving photo-absorption or emission properties of nearby chromophores such as molecular dyes or quantum dots. The electric field of the plasmon can couple with the excitation dipole of a chromophore, perturbing the electronic states involved in the transition and leading to increased absorption and emission rates. These enhancements can also be negated at close distances by energy transfer mechanism, making the spatial arrangement of the two species critical. Ultimately, enhancement of light harvesting efficiency in plasmonic solar cells could lead to thinner and, therefore, lower cost devices. The development of hybrid core/shell particles could offer a solution to this issue. The addition of a dielectric spacer between a gold nanoparticles and a chromophore is the proposed method to control the exciton plasmon coupling strength and thereby balance losses with the plasmonic gains. A detailed procedure for the coating of gold nanoparticles with CdS and ZnS semiconductor shells is presented. The nanoparticles show high uniformity with size control in both the core gold particles and shell species allowing for a more accurate investigation into the plasmonic enhancement of external chromophores.

The synthesis of uniform gold nanoparticles coated with semiconductor shells of CdS or ZnS is performed. The semiconductor coating is conducted by first depositing a silver sulfide shell and exchanging the silver cations for zinc or cadmium cations.

合成，表征和混合金/硫化镉和Au / ZnS核/壳纳米颗粒功能化

Plasmonic nanoparticles are an attractive material for light harvesting applications due to their easily modified surface, high surface area and large ...

Electroactive Polymer Nanoparticles Exhibiting Photothermal Properties

A method for the synthesis of electroactive polymers is demonstrated, starting with the synthesis of extended conjugation monomers using a three-step process that finishes with Negishi coupling. Negishi coupling is a cross-coupling process in which a chemical precursor is first lithiated, followed by transmetallation with ZnCl2. The resultant organozinc compound can be coupled to a dibrominated aromatic precursor to give the conjugated monomer. Polymer films can be prepared via electropolymerization of the monomer and characterized using cyclic voltammetry and ultraviolet-visible-near infrared (UV-Vis-NIR) spectroscopy. Nanoparticles (NPs) are prepared via emulsion polymerization of the monomer using a two-surfactant system to yield an aqueous dispersion of the polymer NPs. The NPs are characterized using dynamic light scattering, electron microscopy, and UV-Vis-NIR-spectroscopy. Cytocompatibility of NPs is investigated using the cell viability assay. Finally, the NP suspensions are irradiated with a NIR laser to determine their effectiveness as potential materials for photothermal therapy (PTT).

A protocol is presented for the synthesis and preparation of nanoparticles consisting of electroactive polymers.

电活性聚合物纳米粒子参展光热特性

A method for the synthesis of electroactive polymers is demonstrated, starting with the synthesis of extended conjugation monomers using a three-step ...

Colloidal Synthesis of Nanopatch Antennas for Applications in Plasmonics and Nanophotonics

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 nanoscale patch antennas. This includes a detailed procedure for the fabrication of thin films with a well-controlled thickness over macroscopic areas using layer-by-layer deposition of polyelectrolyte polymers, namely poly(allylamine) hydrochloride (PAH) and polystyrene sulfonate (PSS). These polyelectrolyte spacer layers serve as a dielectric gap in between silver nanocubes and a gold film. By controlling the size of the nanocubes or the gap thickness, the plasmon resonance can be tuned from about 500 nm to 700 nm. Next, we demonstrate how to incorporate organic sulfo-cyanine5 carboxylic acid (Cy5) dye molecules into the dielectric polymer gap region of the nanopatch antennas. Finally, we show greatly enhanced fluorescence of the Cy5 dyes by spectrally matching the plasmon resonance with the excitation energy and the Cy5 absorption peak. The method presented here enables the fabrication of plasmonic nanopatch antennas with well-controlled dimensions utilizing colloidal synthesis and a layer-by-layer dip-coating process with the potential for low cost and large-scale production. These nanopatch antennas hold great promise for practical applications, for example in sensing, ultrafast optoelectronic devices and for high-efficiency photodetectors.

A protocol for the colloidal synthesis of silver nanocubes and fabrication of plasmonic nanoscale patch antennas with sub-10 nm gaps is presented.

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 ...

In Situ Synthesis of Gold Nanoparticles without Aggregation in the Interlayer Space of Layered Titanate Transparent Films

Combinations of metal oxide semiconductors and gold nanoparticles (AuNPs) have been investigated as new types of materials. The in situ synthesis of AuNPs within the interlayer space of semiconducting layered titania nanosheet (TNS) films was investigated here. Two types of intermediate films (i.e., TNS films containing methyl viologen (TNS/MV2+) and 2-ammoniumethanethiol (TNS/2-AET+)) were prepared. The two intermediate films were soaked in an aqueous tetrachloroauric(III) acid (HAuCl4) solution, whereby considerable amounts of Au(III) species were accommodated within the interlayer spaces of the TNS films. The two types of obtained films were then soaked in an aqueous sodium tetrahydroborate (NaBH4) solution, whereupon the color of the films immediately changed from colorless to purple, suggesting the formation of AuNPs within the TNS interlayer. When only TNS/MV2+ was used as the intermediate film, the color of the film gradually changed from metallic purple to dusty purple within 30 min, suggesting that aggregation of AuNPs had occurred. In contrast, this color change was suppressed by using the TNS/2-AET+ intermediate film, and the AuNPs were stabilized for over 4 months, as evidenced by the characteristic extinction (absorption and scattering) band from the AuNPs.

In Situ Synthesis of Gold Nanoparticles without Aggregation in the Interlayer Space of Layered Titanate Transparent Films

Here, we present a protocol for the in situ synthesis of gold nanoparticles (AuNPs) within the interlayer space of layered titanate films without the aggregation of AuNPs. No spectral change was observed even after 4 months. The synthesized material has expected applications in catalysis, photo-catalysis, and the development of cost-effective plasmonic devices.

在没有聚集的层状钛酸盐薄膜透明的层间金纳米粒子的原位合成

Combinations of metal oxide semiconductors and gold nanoparticles (AuNPs) have been investigated as new types of materials. The in situ synthesis of AuNPs ...

Photodeposition of Pd onto Colloidal Au Nanorods by Surface Plasmon Excitation

A protocol is described to photocatalytically guide Pd deposition onto Au nanorods (AuNR) using surface plasmon resonance (SPR). Excited plasmonic hot electrons upon SPR irradiation drive reductive deposition of Pd on colloidal AuNR in the presence of [PdCl4]2-. Plasmon-driven reduction of secondary metals potentiates covalent, sub-wavelength deposition at targeted locations coinciding with electric field &#8220;hot-spots&#8221; of the plasmonic substrate using an external field (e.g., laser). The process described herein details a solution-phase deposition of a catalytically-active noble metal (Pd) from a transition metal halide salt (H2PdCl4) onto aqueously-suspended, anisotropic plasmonic structures (AuNR). The solution-phase process is amenable to making other bimetallic architectures. Transmission UV-vis monitoring of the photochemical reaction, coupled with ex situ XPS and statistical TEM analysis, provide immediate experimental feedback to evaluate properties of the bimetallic structures as they evolve during the photocatalytic reaction. Resonant plasmon irradiation of AuNR in the presence of [PdCl4]2- creates a thin, covalently-bound Pd0 shell without any significant dampening effect on its plasmonic behavior in this representative experiment/batch. Overall, plasmonic photodeposition offers an alternative route for high-volume, economical synthesis of optoelectronic materials with sub-5 nm features (e.g., heterometallic photocatalysts or optoelectronic interconnects).

A protocol for anisotropic photodeposition of Pd onto aqueously-suspended Au nanorods via localized surface plasmon excitation is presented.

通过表面等离子体激发将 Pd 光沉积到胶体 Au 纳米棒上

A protocol is described to photocatalytically guide Pd deposition onto Au nanorods (AuNR) using surface plasmon resonance (SPR). Excited plasmonic hot ...

Preparation of Silver-Palladium Alloyed Nanoparticles for Plasmonic Catalysis under Visible-Light Illumination

Localized surface plasmon resonance (LSPR) in plasmonic nanoparticles (NPs) can accelerate and control the selectivity of a variety of molecular transformations. This opens possibilities for the use of visible or near-IR light as a sustainable input to drive and control reactions when plasmonic nanoparticles supporting LSPR excitation in these ranges are employed as catalysts. Unfortunately, this is not the case for several catalytic metals such as palladium (Pd). One strategy to overcome this limitation is to employ bimetallic NPs containing plasmonic and catalytic metals. In this case, the LSPR excitation in the plasmonic metal can contribute to accelerate and control transformations driven by the catalytic component. The method reported herein focuses on the synthesis of bimetallic silver-palladium (Ag-Pd) NPs supported on ZrO2 (Ag-Pd/ZrO2) that acts as a plasmonic-catalytic system. The NPs were prepared by co-impregnation of corresponding metal precursors on the ZrO2 support followed by simultaneous reduction leading to the formation of bimetallic NPs directly on the ZrO2 support. The Ag-Pd/ZrO2 NPs were then used as plasmonic catalysts for the reduction of nitrobenzene under 425 nm illumination by LED lamps. Using gas chromatography (GC), the conversion and selectivity of the reduction reaction under the dark and light irradiation conditions can be monitored, demonstrating the enhanced catalytic performance and control over selectivity under LSPR excitation after alloying non-plasmonic Pd with plasmonic metal Ag. This technique can be adapted to a wide range of molecular transformations and NPs compositions, making it useful for the characterization of the plasmonic catalytic activity of different types of catalysis in terms of conversion and selectivity.

Presented here is a protocol for the synthesis of silver-palladium (Ag-Pd) alloy nanoparticles (NPs) supported on ZrO2 (Ag-Pd/ZrO2). This system allows for harvesting energy from visible light irradiation to accelerate and control molecular transformations. This is illustrated by nitrobenzene reduction under light irradiation catalyzed by Ag-Pd/ZrO2 NPs.

在可见光照射下为质子催化准备银-铂合金纳米粒子

Localized surface plasmon resonance (LSPR) in plasmonic nanoparticles (NPs) can accelerate and control the selectivity of a variety of molecular ...

Stable Aqueous Suspensions of Manganese Ferrite Clusters with Tunable Nanoscale Dimension and Composition

Manganese ferrite clusters (MFCs) are spherical assemblies of tens to hundreds of primary nanocrystals whose magnetic properties are valuable in diverse applications. Here we describe how to form these materials in a hydrothermal process that permits the independent control of product cluster size (from 30 to 120 nm) and manganese content of the resulting material. Parameters such as the total amount of water added to the alcoholic reaction media and the ratio of manganese to iron precursor are important factors in achieving multiple types of MFC nanoscale products. A fast purification method uses magnetic separation to recover the materials making production of grams of magnetic nanomaterials quite efficient. We overcome the challenge of magnetic nanomaterial aggregation by applying highly charged sulfonate polymers to the surface of these nanomaterials yielding colloidally stable MFCs that remain non-aggregating even in highly saline environments. These non-aggregating, uniform, and tunable materials are excellent prospective materials for biomedical and environmental applications.

We report a one-pot hydrothermal synthesis of manganese ferrite clusters (MFCs) that offers independent control over material dimension and composition. Magnetic separation allows rapid purification while surface functionalization using sulfonated polymers ensures the materials are non-aggregating in biologically relevant medium. The resulting products are well positioned for biomedical applications.

具有可调纳米尺度尺寸和成分的锰铁氧体簇的稳定水悬浮液

Manganese ferrite clusters (MFCs) are spherical assemblies of tens to hundreds of primary nanocrystals whose magnetic properties are valuable in diverse ...

多功能混合铁

摘要

探索更多视频

此视频中的章节