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
Summary
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.
Abstract
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.
Introduction
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。
Protocol
Representative Results
Discussion
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?…
Disclosures
The authors have nothing to disclose.
Acknowledgements
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.
Materials
| Name of Material/ Equipment | Company | Catalog Number | Comments/Description |
| Poly(3,4-ethylenedioxythiophene):poly-(styrenesulfonate) | Heraeus | Clevios PVP AI 4083 | |
| poly(3- hexylthiophene-2,5-diyl) | Rieke Metals Inc. | P3HT: P200 | |
| phenyl-C61 -butyric acid methyl ester | 1- Material | PC61BM | |
| 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}) | 1- Material | PTB7 | |
| phenyl-C61 -butyric acid methyl ester | Solenne | PC71BM | |
| 1,8-Diiodooctane | Sigma Aldrich | 250295 | |
| Chlorobenzene | Sigma Aldrich | 284513 | |
| Indium Tin Oxide Coated Glass 15 Ohm/SQ | Lumtec | ||
| S1813 | UTD Cleanroom | ||
| MF311 | UTD Cleanroom | ||
| HCl | UTD Cleanroom | ||
| Acetone | Fisher Scientific | A18-20 | |
| Toluene | Fisher Scientific | T323-20 | |
| Methanol | BDH | BDH1135-19L | |
| Isopropanol | Fisher Scientific | A416-20 | |
| CEE Spincoater | Brewer Scientific | http://www.utdallas.edu/research/cleanroom/tools/CEESpinCoater.htm | |
| Contact Printer | Quintel | Q4000-6 | http://www.utdallas.edu/research/cleanroom/QuintelPrinter.htm |
| CPK Spin Processor | http://www.utdallas.edu/research/cleanroom/tools/CPKsolvent.htm | ||
| Spin Coater | Laurell | WS-400-6NPP/LITE | |
| Glove Box | M-Braun | Lab Master 130 | |
| Solar Simulator | Thermo Oriel/Newport | ||
| Keithley 2400 SMU | Keithley/Techtronix | 2400 | |
| Keithley 7002 Multiplexer | Keithley/Techtronix | 7002 | |
| Ultrasonic Cleaner | Kendal | HB-S-49HDT | |
| Micropipette | Eppendorf | 200uL | |
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