Name: ambient method for the production of an ionically gated carbon nanotube common cathode in tandem organic solar cells
Uploaded: 2014-11-05T15:00:00.000+00:00
Duration: 14 min 37 s
Description: Watch this Scientific Journal Video about Ambient Method for the Production of an Ionically Gated Carbon Nanotube Common Cathode in Tandem Organic Solar Cells at JoVE.com

Support for this work was provided by DOE STTR grant DE-SC0003664 on Parallel Tandem Organic Solar Cells with Carbon Nanotube Sheet Interlayers and Welch Foundation grant AT-1617. The authors thank J. Bykova for providing CNT forests and A. R. Howard, K. Meilczarek, and J. Velten for technical assistance and useful discussions.

1.铟锡氧化物（ITO）的图案化和清洗注:使用15Ω/□的ITO玻璃，以及购买或削减ITO玻璃为适合旋涂和光刻尺寸。它是最有效的执行步骤1.1-1.7上的一块玻璃尽可能大的，然后把它切成更小的设备。还注意的是，步骤1.1-1.7所需要的ITO玻璃被导向与ITO的一面朝上。这可以很容易地用万用表的电阻设置进行检查。 <ol><li>旋涂将1ml S1813阳性光致抗蚀剂到ITO玻璃的ITO侧在1分钟的速率为3000转。使用更多的抵御较大的玻璃碎片，确保整个玻璃涂层，并开始旋转涂布机之前删除任何气泡。 </li><li>退火的抗蚀剂涂布的玻璃，在热板上，在115℃下1分钟。 </li><li>加载样品和掩模上的接触对准。 </li><li>揭露光刻胶涂布ITO玻璃的Appro公司priate时间。曝光时间大约是10秒，但改变该时间基于所述UV灯的强度，光致抗蚀剂的类型和厚度。 </li><li>开发UV暴露在基板MF311开发。自旋处理器的自动化过程中产生的最好的和最可重复的结果，但发展可以手工完成的遵循。 <ol><li>淹没的紫外线曝光的衬底为在显影剂1分钟，随后漂洗在去离子（DI）水中，并用氮气枪干燥。因为开发人员很快失去强度，更换样品之间的开发者，或者重复使用开发时交替增加开发时间。 </li></ol></li><li>蚀刻在浓盐酸（HCl）在ITO基材上。这需要5-10分钟之间依赖于盐酸的浓度。冲洗的去离子水，干燥，并测试蚀刻部分的电阻率用万用表。如果任何导电性依然存在，蚀刻的时间较长。 </li><li>一旦蚀刻完成后，除去p-hotoresist用丙酮。注意，迅速清除该光致抗蚀剂可以防止残余的HCl从过蚀刻所述图案化的ITO。 </li><li>如果需要的话，切蚀刻ITO玻璃基板成设备的尺寸。 </li><li>干净的浴中超声发生器的ITO基材中溶剂的顺序 - 去离子水，丙酮，甲苯，甲醇，最后异丙醇。 </li></ol> 2. OPV子细胞的制备<ol><li>准备P3HT:PC 61 BM的解决方案。 注:对于最一致的结果，在氮气环境中制备的溶液。因此能够按照此过程中的环境条件。 <ol><li>找到并记下了两个干净的，〜4个毫升的玻璃小瓶和他们的帽子的质量，并与记号笔标注从另一个区别开来。 </li><li>在氮气或氩气的手套箱中，转移大约10毫克的聚（3-己基噻吩-2,5-二基）（P3HT）的一个小瓶中，大约10毫克的苯基-C 61 -丁酸甲酯（PÇ61 BM）到另一个。 </li><li>再次称重小瓶找到P3HT与PC 61 BM的质量。 </li><li>传输与P3HT和PC 61 BM小瓶到手套箱的解决方案制定过程的其余部分。 </li><li>加入磁力搅拌棒放入每个小瓶中，然后够氯苯添加到每个创建45毫克/毫升的溶液。 </li><li>放置在磁力搅拌下加热板的解决方案，在55℃下为约2小时或直到溶质已完全溶解。 </li><li>混合的P3HT和个人电脑61等体积的BM溶液一起，并让该混合溶液搅拌为在使用前1小时。 </li></ol></li><li>准备PTB7:PC 71 BM的解决方案。 <ol><li>重复步骤2.1.1至2.1.4与poly({4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl}{3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl}) （PTB7）和苯基- 7,1 -丁酸甲酯（PC 71 BM）代替P3HT和PC61 BM。 </li><li>使3％的混合物（体积）1,8- diiodooctane（DIO）的氯苯。这种混合物称为DIO-CB。 </li><li>加入磁力搅拌棒放入每个小瓶中，然后加入足量的DIO-CB的PTB7小瓶有12毫克/毫升的溶液和足够的DIO-CB到PC 71 BM小瓶有40毫克/毫升的溶液。 </li><li>让这些溶液搅拌的加热板上，在70℃下搅拌2天。 </li><li>混合溶液中PTB7的PC机71 1 BM〜1.5的重量比。 </li><li>让使用在70℃下将混合溶液搅拌一小时之前。 </li></ol></li><li>通过0.45μm孔径的尼龙过滤器过滤聚（3,4-亚乙二氧基）:聚（苯乙烯磺酸盐）（PSS的PEDOT）。注意:此过程使用P VP AI4083。 </li><li>旋转涂覆活性层。 <ol><li>置于清洁的ITO基板，ITO-朝上，变成紫外线臭氧清洁器5分钟。 </li><li>旋涂层120微升过滤的PEDOT:PSS到紫外线臭氧处理，图案化的ITO-玻璃基板s的转数3000rpm，1分钟。这应该产生一个30纳米厚的层。 </li><li>退火的PEDOT:PSS涂覆的ITO基材5分钟，在180℃下。 </li><li>旋涂层70微升混合的P3HT:PC 61 BM溶液涂布PEDOT:PSS涂覆的ITO基板在大约1,000rpm的转速1分钟。变化的速率根据需要以沉积200nm厚的有源层。 </li><li>退火的P3HT:PC 61 BM涂覆的基材在170℃下5分钟。结果可能会在最佳的退火温度而变化。 </li><li>旋涂层70微升混合PTB7的:PC 71 BM溶液涂布PEDOT:PSS涂覆的ITO基板在大约700rpm的转速1分钟。变化的速率根据需要以沉积100nm厚的有源层。 </li><li>加载PTB7:PC 71 BM涂覆的基材成高真空（&lt;2×10 -6 Torr）的腔室，以除去残留的DIO。通常情况下，保留样品室O / N。 </li></ol></li></ol> 3.编造汇接设备 &lt;OL&gt; <li>层压CNT电极。 <ol><li>切PTB7和P3HT基板的一半，使串联设备。一个专门ITO图案并不需要这一步。在ITO图案应具有至少两个平行的ITO电极从一个边缘延伸到1毫米远离另一个。 </li><li>首先通过从玻璃的边缘聚合物和PEDOT擦去制备PTB7和P3HT的涂覆的基材，和露出的ITO条如在图1的第一面板看到哪个将用作公共电极。 </li><li>层叠的PTB7和P3HT电极上边所述CNT公共电极。通过将滤纸在CNT侧的设备上，轻轻按压，然后剥离该滤纸远离施加的SWCNT膜。这示于图1中的第二面板。 </li><li>通过将甲氧基-九氟丁烷致密化的CNT电极上的表面（C 4 F 9 OCH 3）（HFE）和通过涂布该CNT具有小amou液体新台币，然后让它干枯脱落。 </li><li>擦去在ITO上的顶部和玻璃将具有栅电极， 如图1中的第三面板的聚合物和CNT，从玻璃中取出所有的聚合物，以防止用刀片栅极泄漏。 </li><li>层叠在CNT栅电极上PTB7和P3HT涂覆的基材的清洁区域。通过从多壁碳纳米管林用刀片的边缘拉层叠的多壁碳纳米管，并让片立自如一些毛细管之间。通过独立片传递设备层叠在CNT上的设备。栅极电极应具有层的2-3倍的数量为铺设到共用电极。 </li><li>压实与HFE栅电极。 </li></ol></li><li>放置离子液体的一小滴（≈10微升），N，N- -Diethyl- N-甲基-N - （2-甲氧基乙基）铵四氟硼酸盐，DEME-BF 4，在一个两CNT电极的顶的底物。 </li><li>小心地放置在衬底上，而不具有离子液体上的每个-其他顶部共用电极和栅电极的基板的顶部的离子型液体。这示于图1中的最后一个面板。 </li><li>放置有孔径大小比在有源区域中的电极尺寸较小的光掩模。使用小片段以保持光掩模的地方，以及在测试过程中保持在一起的装置。 </li></ol> 4.测量设备<ol><li>传送装置进入测量手套箱。 </li><li>进行电气连接。 <ol><li>连接的共用电极，并与共同作为接地的栅极电极之间的栅极供电。 </li><li>连接两个ITO阳极到它们被连接到一个开关，它允许用户选择任一阳极或两者的阳极导线。 </li><li>该开关的输出端连接到所述源测量单元的输入端。 </li><li>连接源MEAS的理由茜单元对共用电极。 </li></ol></li><li>通过反复的升V 闸以下步骤测量设备的IV特性。 <ol><li>设V 闸下一个值，从V 闸 0.25 V.增量开始= 0 V至V 闸 = 2 V </li><li>等待5分钟，或直至栅极电流是稳定的。理想的情况下，栅极电流应稳定在毫微安的10秒。 </li><li>将开关设置到两个子细胞中。 </li><li>打开电灯快门。 </li><li>运行电压扫描的源测量单元从-1伏到1伏在约100增量或更多。 </li><li>运行1伏电压扫描到-1伏。 </li><li>关闭灯快门。 </li><li>再次运行电压扫描。 </li><li>将开关设置到前面的子细胞。 </li><li>重复步骤4.3.4至4.3.8。 </li><li>将开关设置到后面的子细胞。 </li><li>重复步骤4.3.4至4.3.8。 </li></ol></li><li>计算装置的参数。 &lt;OL&gt; <li>发现每个子小区在每个V 栅的短路电流（J SC），通过确定当前由该装置时产生跨过子小区的电压为0V。 </li><li>发现每个子小区在每个V 闸的开路电压（V OC），通过找到由该装置所产生的电压，当电流通过子小区是0A。 </li><li>发现从太阳能电池的输出最大功率乘以各电压值与各电流值，选择最大（最负）值。这假定1测量光生电流作为负电流。 </li><li>发现功率转换效率（η）除以最大功率由输入光功率。 </li><li>找到的填充因子（FF）除以最大功率地被J SC和V OC的乘积。 </li></ol></li></ol>

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The authors have nothing to disclose.

设计并行串联太阳能电池时，研究结果强调了几个方面的考虑。值得注意的是，如果该子单元的一个表现不佳，在串联的性能产生负面影响。结果表明，存在两个主要的效果。如果一个子单元被短路， 例如 ，示出的欧姆特性，在FF T将不会比坏子小区的FF更高。 Ĵ 牛逼 SC和V T，OC将受到类似的影响。是这种情况时，V 闸低，P3HT子小区还没有?...

聚合物半导体是领先的有机光伏（OPV）材料，由于高吸收率，良好的输送性，柔韧性，和兼容性与温度敏感的基材。 OPV器件的电源转换效率，η，有显著在过去几年里跳下来，单电池效率高达9.1％1，使他们日益可行的能源技术。 尽管η改进，薄最佳的活性层厚度的设备的限制光的吸收，阻碍可靠的制造。此外，各聚合物的光吸收频谱宽度是有限相比，无机材料。不同的光谱感光度的配对聚合物绕过这些困难，使得串联结构2的必要的创新。 串联的串联装置是最常见的串联结构。在本设计中，电子传输相关材料人，一个可选的金属结合层，和空穴传输层连接两个独立的光敏层被称为子单元。在串联配置连接子细胞增加了组合装置的开路电压。一些基团已与简并掺杂输运层3成功- 5，但更多组已使用的金或银颗粒以帮助空穴和电子的复合而在层间6,7。 与此相反，平行串联物需要高导电性的电极，无论是阳极或阴极，连接两个有源层。间必须是高度透明的，这限制了含有金属颗粒系列串联隔层，并且更是由于薄的，连续的金属电极构成的平行串列夹层。碳纳米管（CNT）的片材显示出比金属层更高的透明度。因此，纳米技术研究所，与岛根大学合作，具有INTroduced使用如单片，平行汇接设备8的层间电极的概念。 以前的努力功能单一，平行，串联OPV与碳纳米管片材用作中间层的阳极8,9的设备。这些方法需要特别的照顾，当沉积层后，以避免一个或两个细胞或损坏之前的层短路。在本文中描述的新方法，通过将所述CNT电极上的两个单电池的聚合物活性层的顶部简化制造，然后层叠在两个分离的设备一起，如图1中所示。此方法是显着的设备，包括一个空气-STABLE CNT阴极，可在环境条件下制造的完全只采用干和解决方案处理。 碳纳米管片材是不本质上良好的阴极，因为它们需要n型掺杂来降低功函数，以收集从光活性区中的电子一个太阳能电池10。双电层中的电解质的充电，如离子性液体，可用于移动CNT的功函数的电极11 - 14。 如在图2中，当栅电压（V 闸 ）是增大描述在前面的纸15和描绘的，该CNT公共电极的功函数被降低，造成电极的不对称性。这可以防止空穴收集从OPV的捐助有利于从OPV的受体收集电子和器件导通，从低效的光敏电阻转变为光电二极管15的行为。还应当指出的是，能用于装置和由于栅极漏电流损失的电力进行充电的琐碎相比由太阳能电池15产生的功率。的碳纳米管电极的离子门控对工作职能有很大的影响，由于国家的低密度和高表面积，以在CNT电极的体积比。类似的方法已被用于提高在碳纳米管与n型Si 16的界面的肖特基势垒。

<table><tbody><tr><td>Poly(3,4-ethylenedioxythiophene):poly-(styrenesulfonate)</td><td>Heraeus</td><td>Clevios PVP AI 4083</td><td></td></tr><tr><td>poly(3-hexylthiophene-2,5-diyl)&amp;nbsp;</td><td>Rieke Metals&amp;nbsp; Inc.</td><td>P3HT:&amp;nbsp; P200</td><td></td></tr><tr><td>phenyl-C&lt;sub&gt;61&lt;/sub&gt;-butyric&amp;nbsp; acid methyl&amp;nbsp; ester</td><td>1- Material</td><td>PC61BM</td><td></td></tr><tr><td>Poly({4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b&amp;prime;]dithiophene-2,6-diyl}{3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl})&amp;nbsp;</td><td>1- Material</td><td>PTB7</td><td></td></tr><tr><td>phenyl-C&lt;sub&gt;61&lt;/sub&gt;-butyric acid methyl&amp;nbsp; ester</td><td>Solenne</td><td>PC71BM</td><td></td></tr><tr><td>1,8-Diiodooctane</td><td>Sigma Aldrich</td><td>250295</td><td></td></tr><tr><td>Chlorobenzene</td><td>Sigma Aldrich</td><td>284513</td><td></td></tr><tr><td>Indium Tin Oxide Coated Glass 15 Ohm/SQ</td><td>Lumtec</td><td></td><td></td></tr><tr><td>S1813</td><td>UTD Cleanroom</td><td></td><td></td></tr><tr><td>MF311</td><td>UTD Cleanroom</td><td></td><td></td></tr><tr><td>HCl</td><td>UTD Cleanroom</td><td></td><td></td></tr><tr><td>Acetone</td><td>Fisher Scientific</td><td>A18-20</td><td></td></tr><tr><td>Toluene</td><td>Fisher Scientific</td><td>T323-20</td><td></td></tr><tr><td>Methanol</td><td>BDH</td><td>BDH1135-19L</td><td></td></tr><tr><td>Isopropanol</td><td>Fisher Scientific</td><td>A416-20</td><td></td></tr><tr><td>CEE Spincoater</td><td>Brewer Scientific</td><td></td><td>http://www.utdallas.edu/research/cleanroom/tools/CEESpinCoater.htm</td></tr><tr><td>Contact Printer</td><td>Quintel</td><td>Q4000-6</td><td>http://www.utdallas.edu/research/cleanroom/QuintelPrinter.htm</td></tr><tr><td>CPK Spin Processor</td><td></td><td></td><td>http://www.utdallas.edu/research/cleanroom/tools/CPKsolvent.htm</td></tr><tr><td>Spin Coater</td><td>Laurell</td><td>WS-400-6NPP/LITE</td><td></td></tr><tr><td colspan="4">[header]</td></tr><tr><td>Glove Box</td><td>M-Braun</td><td>Lab Master 130</td><td></td></tr><tr><td>Solar Simulator</td><td>Thermo Oriel/Newport</td><td></td><td></td></tr><tr><td>Keithley 2400 SMU</td><td>Keithley/Techtronix</td><td>2400</td><td></td></tr><tr><td>Keithley 7002 Multiplexer</td><td>Keithley/Techtronix</td><td>7002</td><td></td></tr><tr><td>Ultrasonic Cleaner</td><td>Kendal</td><td>HB-S-49HDT</td><td></td></tr><tr><td>Micropipette</td><td>Eppendorf</td><td>200 &amp;micro;l</td><td></td></tr></tbody></table>

ambient method for the production of an ionically gated carbon nanotube common cathode in tandem organic solar cells

A method of fabricating organic photovoltaic (OPV) tandems that requires no vacuum processing is presented. These devices are comprised of two solution-processed polymeric cells connected in parallel by a transparent carbon nanotubes (CNT) interlayer. This structure includes improvements in fabrication techniques for tandem OPV devices. First the need for ambient-processed cathodes is considered. The CNT anode in the tandem device is tuned via ionic gating to become a common cathode. Ionic gating employs electric double layer charging to lower the work function of the CNT electrode. Secondly, the difficulty of sequentially stacking tandem layers by solution-processing is addressed. The devices are fabricated via solution and dry-lamination in ambient conditions with parallel processing steps. The method of fabricating the individual polymeric cells, the steps needed to laminate them together with a common CNT cathode, and then provide some representative results are described. These results demonstrate ionic gating of the CNT electrode to create a common cathode and addition of current and efficiency as a result of the lamination procedure.

从不同的聚合物，显著不同的带隙特别是聚合物，形成串联设备的实际利益，因为这些设备可以吸收光线的最大的光谱范围。在此器件结构中，PTB7子小区是背面细胞和P3HT是前面的子小区。这是为了吸收的光的量最大为P3HT子小区在很大程度上是透明的，由PTB7子细胞吸收的波长更长的光。为清楚起见，太阳能电池的参数，V OC，J SC，FF和η指的是串联，前面或分别回单元时将被装饰的标T?...

Watch this Scientific Journal Video about Ambient Method for the Production of an Ionically Gated Carbon Nanotube Common Cathode in Tandem Organic Solar Cells at JoVE.com

Ambient Method for the Production of an Ionically Gated Carbon Nanotube Common Cathode in Tandem Organic Solar Cells

A method of fabricating, in ambient conditions, organic photovoltaic tandem devices in a parallel configuration is presented. These devices feature an air-processed, semi-transparent, carbon nanotube common cathode.

对于一个以离子门控碳纳米管共阴极的串联有机太阳能电池的生产环境法

A method of fabricating organic photovoltaic (OPV) tandems that requires no vacuum processing is presented. These devices are comprised of two ...

ambient-method-for-production-an-ionically-gated-carbon-nanotube

Research

JoVE Journal

Engineering

9.4K 次观看.  The University of Texas at Dallas. A method of fabricating, in ambient conditions, organic photovoltaic tandem devices in a parallel configuration is presented. These devices feature an air-processed, semi-transparent, carbon nanotube common cathode.

视频: Ambient Method for the Production of an Ionically Gated Carbon Nanotube Common Cathode in Tandem Organic Solar Cells

Harvesting Solar Energy by Means of Charge-Separating Nanocrystals and Their Solids

Conjoining different semiconductor materials in a single nano-composite provides synthetic means for the development of novel optoelectronic materials offering a superior control over the spatial distribution of charge carriers across material interfaces. As this study demonstrates, a combination of donor-acceptor nanocrystal (NC) domains in a single nanoparticle can lead to the realization of efficient photocatalytic1-5 materials, while a layered assembly of donor- and acceptor-like nanocrystals films gives rise to photovoltaic materials.
Initially the paper focuses on the synthesis of composite inorganic nanocrystals, comprising linearly stacked ZnSe, CdS, and Pt domains, which jointly promote photoinduced charge separation. These structures are used in aqueous solutions for the photocatalysis of water under solar radiation, resulting in the production of H2 gas. To enhance the photoinduced separation of charges, a nanorod morphology with a linear gradient originating from an intrinsic electric field is used5. The inter-domain energetics are then optimized to drive photogenerated electrons toward the Pt catalytic site while expelling the holes to the surface of ZnSe domains for sacrificial regeneration (via methanol). Here we show that the only efficient way to produce hydrogen is to use electron-donating ligands to passivate the surface states by tuning the energy level alignment at the semiconductor-ligand interface. Stable and efficient reduction of water is allowed by these ligands due to the fact that they fill vacancies in the valence band of the semiconductor domain, preventing energetic holes from degrading it. Specifically, we show that the energy of the hole is transferred to the ligand moiety, leaving the semiconductor domain functional. This enables us to return the entire nanocrystal-ligand system to a functional state, when the ligands are degraded, by simply adding fresh ligands to the system4.
To promote a photovoltaic charge separation, we use a composite two-layer solid of PbS and TiO2 films. In this configuration, photoinduced electrons are injected into TiO2 and are subsequently picked up by an FTO electrode, while holes are channeled to a Au electrode via PbS layer6. To develop the latter we introduce a Semiconductor Matrix Encapsulated Nanocrystal Arrays (SMENA) strategy, which allows bonding PbS NCs into the surrounding matrix of CdS semiconductor. As a result, fabricated solids exhibit excellent thermal stability, attributed to the heteroepitaxial structure of nanocrystal-matrix interfaces, and show compelling light-harvesting performance in prototype solar cells7.

A general strategy for the development of charge-separating semiconductor nanocrystal composites deployable for solar energy production is presented. We show that assembly of donor-acceptor nanocrystal domains in a single nanoparticle geometry gives rise to a photocatalytic function, while bulk-heterojunctions of donor-acceptor nanocrystal films can be used for photovoltaic energy conversion.

通过电荷分离纳米晶及其固体收获太阳能

Conjoining different semiconductor materials in a single nano-composite provides synthetic means for the development of novel optoelectronic materials ...

科研

工程学

Ultrahigh Density Array of Vertically Aligned Small-molecular Organic Nanowires on Arbitrary Substrates

In recent years &pi;-conjugated organic semiconductors have emerged as the active material in a number of diverse applications including large-area, low-cost displays, photovoltaics, printable and flexible electronics and organic spin valves. Organics allow (a) low-cost, low-temperature processing and (b) molecular-level design of electronic, optical and spin transport characteristics. Such features are not readily available for mainstream inorganic semiconductors, which have enabled organics to carve a niche in the silicon-dominated electronics market. The first generation of organic-based devices has focused on thin film geometries, grown by physical vapor deposition or solution processing. However, it has been realized that organic nanostructures can be used to enhance performance of above-mentioned applications and significant effort has been invested in exploring methods for organic nanostructure fabrication.	
A particularly interesting class of organic nanostructures is the one in which vertically oriented organic nanowires, nanorods or nanotubes are organized in a well-regimented, high-density array. Such structures are highly versatile and are ideal morphological architectures for various applications such as chemical sensors, split-dipole nanoantennas, photovoltaic devices with radially heterostructured "core-shell" nanowires, and memory devices with a cross-point geometry. Such architecture is generally realized by a template-directed approach. In the past this method has been used to grow metal and inorganic semiconductor nanowire arrays. More recently &pi;-conjugated polymer nanowires have been grown within nanoporous templates. However, these approaches have had limited success in growing nanowires of technologically important &pi;-conjugated small molecular weight organics, such as tris-8-hydroxyquinoline aluminum (Alq3), rubrene and methanofullerenes, which are commonly used in diverse areas including organic displays, photovoltaics, thin film transistors and spintronics.	
Recently we have been able to address the above-mentioned issue by employing a novel "centrifugation-assisted" approach. This method therefore broadens the spectrum of organic materials that can be patterned in a vertically ordered nanowire array. Due to the technological importance of Alq3, rubrene and methanofullerenes, our method can be used to explore how the nanostructuring of these materials affects the performance of aforementioned organic devices. The purpose of this article is to describe the technical details of the above-mentioned protocol, demonstrate how this process can be extended to grow small-molecular organic nanowires on arbitrary substrates and finally, to discuss the critical steps, limitations, possible modifications, trouble-shooting and future applications.

We report a simple method for fabricating an ultrahigh density array of vertically ordered small-molecular organic nanowires. This method allows for synthesis of complex heterostructured hybrid nanowire geometries, which can be inexpensively grown on arbitrary substrates. These structures have potential applications in organic electronics, optoelectronics, chemical sensing, photovoltaics and spintronics.

超高密度垂直对齐的任意基质的小分子有机纳米线阵列

In  recent years &pi;-conjugated  organic semiconductors have emerged as the active material in a number of  diverse applications including large-area, ...

Integrating a Triplet-triplet Annihilation Up-conversion System to Enhance Dye-sensitized Solar Cell Response to Sub-bandgap Light

The poor response of dye-sensitized solar cells (DSCs) to red and infrared light is a significant impediment to the realization of higher photocurrents and hence higher efficiencies. Photon up-conversion by way of triplet-triplet annihilation (TTA-UC) is an attractive technique for using these otherwise wasted low energy photons to produce photocurrent, while not interfering with the photoanodic performance in a deleterious manner. Further to this, TTA-UC has a number of features, distinct from other reported photon up-conversion technologies, which renders it particularly suitable for coupling with DSC technology. In this work, a proven high performance TTA-UC system, comprising a palladium porphyrin sensitizer and rubrene emitter, is combined with a high performance DSC (utilizing the organic dye D149) in an integrated device. The device shows an enhanced response to sub-bandgap light over the absorption range of the TTA-UC sub-unit resulting in the highest figure of merit for up-conversion assisted DSC performance to date.

An integrated device, incorporating a dye-sensitized solar cell and triplet-triplet annihilation up-conversion unit was produced, affording enhanced light harvesting, from a wider section of the solar spectrum. Under modest irradiation levels a significantly enhanced response to low energy photons was demonstrated, yielding a record figure of merit for dye-sensitized solar cells.

集成的三重态 - 三重态湮灭上转换系统，提高染料敏化太阳能电池的响应子带隙光

The poor response of dye-sensitized solar cells (DSCs) to red and infrared light is a significant impediment to the realization of higher photocurrents ...

Making Record-efficiency SnS Solar Cells by Thermal Evaporation and Atomic Layer Deposition

Tin sulfide (SnS) is a candidate absorber material for Earth-abundant, non-toxic solar cells. SnS offers easy phase control and rapid growth by congruent thermal evaporation, and it absorbs visible light strongly. However, for a long time the record power conversion efficiency of SnS solar cells remained below 2%. Recently we demonstrated new certified record efficiencies of 4.36% using SnS deposited by atomic layer deposition, and 3.88% using thermal evaporation. Here the fabrication procedure for these record solar cells is described, and the statistical distribution of the fabrication process is reported. The standard deviation of efficiency measured on a single substrate is typically over 0.5%. All steps including substrate selection and cleaning, Mo sputtering for the rear contact (cathode), SnS deposition, annealing, surface passivation, Zn(O,S) buffer layer selection and deposition, transparent conductor (anode) deposition, and metallization are described. On each substrate we fabricate 11 individual devices, each with active area 0.25 cm2. Further, a system for high throughput measurements of current-voltage curves under simulated solar light, and external quantum efficiency measurement with variable light bias is described. With this system we are able to measure full data sets on all 11 devices in an automated manner and in minimal time. These results illustrate the value of studying large sample sets, rather than focusing narrowly on the highest performing devices. Large data sets help us to distinguish and remedy individual loss mechanisms affecting our devices.

Tin sulfide (SnS) is a candidate material for Earth-abundant, non-toxic solar cells. Here, we demonstrate the fabrication procedure of the SnS solar cells employing atomic layer deposition, which yields 4.36% certified power conversion efficiency, and thermal evaporation which yields 3.88%.

通过热蒸发和原子层沉积使记录效率的SnS太阳能电池

Tin sulfide (SnS) is a candidate absorber material for Earth-abundant, non-toxic solar cells. SnS offers easy phase control and rapid growth by congruent ...

Fabrication of Fully Solution Processed Inorganic Nanocrystal Photovoltaic Devices

We demonstrate a method for the preparation of fully solution processed inorganic solar cells from a spin and spray coating deposition of nanocrystal inks. For the photoactive absorber layer, colloidal CdTe and CdSe nanocrystals (3-5 nm) are synthesized using an inert hot injection technique and cleaned with precipitations to remove excess starting reagents. Similarly, gold nanocrystals (3-5 nm) are synthesized under ambient conditions and dissolved in organic solvents. In addition, precursor solutions for transparent conductive indium tin oxide (ITO) films are prepared from solutions of indium and tin salts paired with a reactive oxidizer. Layer-by-layer, these solutions are deposited onto a glass substrate following annealing (200-400 &#176;C) to build the nanocrystal solar cell (glass/ITO/CdSe/CdTe/Au). Pre-annealing ligand exchange is required for CdSe and CdTe nanocrystals where films are dipped in NH4Cl:methanol to replace long-chain native ligands with small inorganic Cl- anions. NH4Cl(s) was found to act as a catalyst for the sintering reaction (as a non-toxic alternative to the conventional CdCl2(s) treatment) leading to grain growth (136&#177;39 nm) during heating. The thickness and roughness of the prepared films are characterized with SEM and optical profilometry. FTIR is used to determine the degree of ligand exchange prior to sintering, and XRD is used to verify the crystallinity and phase of each material. UV/Vis spectra show high visible light transmission through the ITO layer and a red shift in the absorbance of the cadmium chalcogenide nanocrystals after thermal annealing. Current-voltage curves of completed devices are measured under simulated one sun illumination. Small differences in deposition techniques and reagents employed during ligand exchange have been shown to have a profound influence on the device properties. Here, we examine the effects of chemical (sintering and ligand exchange agents) and physical treatments (solution concentration, spray-pressure, annealing time and annealing temperature) on photovoltaic device performance.

This protocol describes the synthesis and solution deposition of inorganic nanocrystals layer by layer to produce thin film electronics on non-conductive surfaces. Solvent-stabilized inks can produce complete photovoltaic devices on glass substrates via spin and spray coating following post-deposition ligand exchange and sintering.

全面解决方案处理的无机纳米晶体光伏器件的制造

We demonstrate a method for the preparation of fully solution processed inorganic solar cells from a spin and spray coating deposition of nanocrystal ...

Morphology Control for Fully Printable Organic&#8211;Inorganic Bulk-heterojunction Solar Cells Based on a Ti-alkoxide and Semiconducting Polymer

The photoactive layer of a typical organic thin-film bulk-heterojunction (BHJ) solar cell commonly uses fullerene derivatives as the electron-accepting material. However, fullerene derivatives are air-sensitive; therefore, air-stable material is needed as an alternative. In the present study, we propose and describe the properties of Ti-alkoxide as an alternative electron-accepting material to fullerene derivatives to create highly air-stable BHJ solar cells. It is well-known that controlling the morphology in the photoactive layer, which is constructed with fullerene derivatives as the electron acceptor, is important for obtaining a high overall efficiency through the solvent method. The conventional solvent method is useful for high-solubility materials, such as fullerene derivatives. However, for Ti-alkoxides, the conventional solvent method is insufficient, because they only dissolve in specific solvents. Here, we demonstrate a new approach to morphology control that uses the molecular bulkiness of Ti-alkoxides without the conventional solvent method. That is, this method is one approach to obtain highly efficient, air-stable, organic-inorganic bulk-heterojunction solar cells.

A method for fully printable, fullerene-free, highly air-stable, bulk-heterojunction solar cells based on Ti alkoxides as the electron acceptor and the electron-donating polymer fabrication is described here. Moreover, a method for controlling the morphology of the photoactive layer through the molecular bulkiness of the Ti-alkoxide units is reported.

基于一个钛醇盐和半导体聚合物为全可印刷有机 - 无机批量异质结太阳能电池形貌控制

The photoactive layer of a typical organic thin-film bulk-heterojunction (BHJ) solar cell commonly uses fullerene derivatives as the electron-accepting ...

Electrospinning of Photocatalytic Electrodes for Dye-sensitized Solar Cells

This work demonstrates a protocol to fabricate a fiber-based photoanode for dye-sensitized solar cells, consisting of a light-scattering layer made of electrospun titanium dioxide nanofibers (TiO2-NFs) on top of a blocking layer made of commercially available titanium dioxide nanoparticles (TiO2-NPs). This is achieved by first electrospinning a solution of titanium (IV) butoxide, polyvinylpyrrolidone (PVP), and glacial acetic acid in ethanol to obtain composite PVP/TiO2 nanofibers. These are then calcined at 500 &#176;C to remove the PVP and to obtain pure anatase-phase titania nanofibers. This material is characterized using scanning electron microscopy (SEM) and powder X-ray diffraction (XRD). The photoanode is prepared by first creating a blocking layer through the deposition of a TiO2-NPs/terpineol slurry on a fluorine-doped tin oxide (FTO) glass slide using doctor blading techniques. A subsequent thermal treatment is performed at 500 &#176;C. Then, the light-scattering layer is formed by depositing a TiO2-NFs/terpineol slurry on the same slide, using the same technique, and calcinating again at 500 &#176;C. The performance of the photoanode is tested by fabricating a dye-sensitized solar cell and measuring its efficiency through J-V curves under a range of incident light densities, from 0.25-1 Sun.

The overall goal of this project was to use electrospinning to fabricate a photoanode with improved performance for dye-sensitized solar cells.

染料敏化太阳能电池的光催化电极的电纺丝

This work demonstrates a protocol to fabricate a fiber-based photoanode for dye-sensitized solar cells, consisting of a light-scattering layer made of ...

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 ...

Fabrication of Robust Nanoscale Contact between a Silver Nanowire Electrode and CdS Buffer Layer in Cu(In,Ga)Se2 Thin-film Solar Cells

Silver nanowire transparent electrodes have been employed as window layers for Cu(In,Ga)Se2 thin-film solar cells. Bare silver nanowire electrodes normally result in very poor cell performance. Embedding or sandwiching silver nanowires using moderately conductive transparent materials, such as indium tin oxide or zinc oxide, can improve cell performance. However, the solution-processed matrix layers can cause a significant number of interfacial defects between transparent electrodes and the CdS buffer, which can eventually result in low cell performance. This manuscript describes how to fabricate robust electrical contact between a silver nanowire electrode and the underlying CdS buffer layer in a Cu(In,Ga)Se2 solar cell, enabling high cell performance using matrix-free silver nanowire transparent electrodes. The matrix-free silver nanowire electrode fabricated by our method proves that the charge-carrier collection capability of silver nanowire electrode-based cells is as good as that of standard cells with sputtered ZnO:Al/i-ZnO as long as the silver nanowires and CdS have high-quality electrical contact. The high-quality electrical contact was achieved by depositing an additional CdS layer as thin as 10 nm onto the silver nanowire surface.

Fabrication of Robust Nanoscale Contact between a Silver Nanowire Electrode and CdS Buffer Layer in CuIn,GaSe2 Thin-film Solar Cells

In this protocol, we describe the detailed experimental procedure for the fabrication of a robust nanoscale contact between a silver nanowire network and CdS buffer layer in a CIGS thin-film solar cell.

在 Cu(In、Ga)Se2薄膜太阳能电池中制造银纳米线电极与 CdS 缓冲层之间的强健纳米级接触

Silver nanowire transparent electrodes have been employed as window layers for Cu(In,Ga)Se2 thin-film solar cells. Bare silver nanowire electrodes ...

In situ Grazing Incidence Small Angle X-ray Scattering on Roll-To-Roll Coating of Organic Solar Cells with Laboratory X-ray Instrumentation

We present an in-house, in situ Grazing Incidence Small Angle X-ray Scattering (GISAXS) experiment, developed to probe the drying kinetics of roll-to-roll slot-die coating of the active layer in organic photovoltaics (OPVs), during deposition. For this demonstration, the focus is on the combination of P3HT:O-IDTBR and P3HT:EH-IDTBR, which have different drying kinetics and device performance, despite their chemical structure only varying slightly by the sidechain of the small molecule acceptor. This article provides a step-by-step guide to perform an in situ GISAXS experiment and demonstrates how to analyze and interpret the results. Usually, performing this type of in situ X-ray experiments to investigate the drying kinetics of the active layer in OPVs relies on access to synchrotrons. However, by using and further developing the method described in this paper, it is possible to perform experiments with a coarse temporal and spatial resolution, on a day-to-day basis to gain fundamental insight in the morphology of drying inks.

This paper is a demonstration and a guideline to perform and analyze in-house (with a laboratory X-ray instrument) in situ GISAXS experiments of drying inks on roll-to-roll slot-die coated, non-fullerene organic photovoltaics.

通过实验室X射线仪器对有机太阳能电池的滚滚涂层进行现场放牧小角度X射线散射

We present an in-house, in situ Grazing Incidence Small Angle X-ray Scattering (GISAXS) experiment, developed to probe the drying kinetics of roll-to-roll ...