狭缝涂布大面积氧化锌薄膜的制备及其在柔性有机太阳能电池中的应用

郭经波; 韩云飞; 龚超; 潘雅琴; 刘立起; 骆群; 马昌期

doi:10.13801/j.cnki.fhclxb.20220428.001

狭缝涂布大面积氧化锌薄膜的制备及其在柔性有机太阳能电池中的应用

doi: 10.13801/j.cnki.fhclxb.20220428.001

郭经波^{1, 2},
韩云飞²,
龚超²,
潘雅琴²,
刘立起^1, ,,
骆群^2, ,,
马昌期²

1.
上海大学　材料科学与工程学院, 上海 200438
2.
中国科学院苏州纳米技术与纳米仿生研究所创新实验室, 苏州 215123

基金项目: 国家自然科学基金 (22075315)；中科院青年创新促进会(2019317)

详细信息

作者简介:
刘立起，上海大学材料学院教师，博士，河北沧州人。2012年博士毕业于东华大学，同年加入上海大学工作。研究方向为复合材料，主要从事高性能纤维制备、碳碳复合材料及石墨烯复合材料等方面的研究工作

骆群，项目研究员。2006年获郑州大学工学学士学位，2011年获浙江大学工学博士学位，期间在法国雷恩一大化学系交流半年。2011年至2014年，苏州纳米所从事博士后研究工作，2015年至今，任副研究员、项目研究员。入选2019年中科院青年促进会会员。研究方向为印刷光电功能材料以及光伏器件，主要从事印刷有机和钙钛矿太阳能电池相关的墨水、印刷工艺开发、高效大面积柔性电池构建以及应用方面的研究工作。迄今在Adv. Mater., Adv. Energy Mater., ACS Nano等期刊发表研究论文60余篇，申请国家发明专利20余项，国际专利2项，其中授权专利8项（含1项国际专利）

通讯作者:
刘立起，博士，硕士生导师，研究方向为碳纤维复合材料、石墨烯材料　 E-mail：llq@shu.edu.cn

骆群，博士，项目研究员，硕士生导师，研究方向为印刷有机和钙钛矿太阳能电池相关的墨水、印刷工艺开发、高效大面积柔性电池构建及应用　E-mail：qluo2011@sinano.ac.cn

中图分类号: TB383.2; TM914.4
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出版历程
- 收稿日期: 2022-04-01
- 修回日期: 2022-04-18
- 录用日期: 2022-04-23
- 网络出版日期: 2022-04-29
- 刊出日期: 2022-03-23

Slot-die coated large-area ZnO films for flexible organic solar cells

GUO Jingbo^{1, 2},
HAN Yunfei²,
GONG Chao²,
PAN Yaqin²,
LIU Liqi^{1
, ,},
LUO Qun^{2
, ,},
MA Changqi²

1.
School of Materials Science and Engineering, Shanghai University, Shanghai 200438, China
2.
i-lab, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China

摘要

摘要: 发展有机太阳能电池的印刷法制备技术是实现有机光伏产业化的关键。在有机光伏器件中，氧化锌是常用的电子传输层材料。氧化锌纳米粒子在印刷过程中的自聚集，以及大面积薄膜干燥的不均匀，严重影响了大面积印刷有机光伏器件的性能。通过调控氧化锌墨水溶剂和引入墨水分散添加剂，获得一种适用于大面积涂布的氧化锌纳米墨水。其中复合溶剂的使用调控了氧化锌墨水的流变特性，进而改善了涂布薄膜中的边缘效应；而乙醇胺添加剂的引入解决了墨水在存放和印刷过程中的聚集问题。该墨水具有18个月以上保存稳定性，以及优异的狭缝涂布适印性。基于上述墨水，采用狭缝涂布方法制备获得的100×100 mm²尺寸的大面积涂布薄膜具有优异的均匀性。将印刷的大面积氧化锌薄膜作为柔性有机太阳能电池的电子传输层，获得1 cm²柔性有机太阳能电池的效率超过了14%，同时表现优异的重复性。
- 有机太阳能电池 /
- 印刷光伏 /
- 狭缝涂布 /
- 氧化锌纳米墨水 /
- 大面积均匀性
Abstract: The preparation of large-area organic solar cells through coating or printing is the key to realizing the industrialization of organic photovoltaics. In the organic solar cells, ZnO is a commonly used material as an electron transporting layer. However, the self-aggregation of ZnO nanoparticles and the uneven drying of films during printing cause large numbers of defects and poor uniformity in large-area films, which seriously affects the perfor-mance of large-area printed organic photovoltaic devices. In this work, a ZnO nanoink suitable for large-area slot-die coating was developed by regulating solvent and introducing an ink dispersion stabilizer. The rheological pro-perties of ZnO nanoink were regulated by using a mixed solvent, which solved the issue of edge effect in the coated film. The introduction of ethanolamine additives solves the problem of ink aggregation during storage and printing, allowing the ink to maintain long-term stability during 18 months of storage. With this nanoink, large-area films with a size of 100×100 mm² were obtained by slot-die coating. Such a film shows excellent film uniformity. Using the printed large-area ZnO films as electron transporting layer, an efficiency of higher than 14% is obtained for 1 cm² flexible organic solar cells.
- organic solar cells /
- printing photovoltaics /
- slot-die coating /
- ZnO nanoink /
- large area uniformity

HTML全文

图 1 ZnO-A (a)、ZnO-B (b)和ZnO-C (c)墨水的DLS测试结果；(d)三种氧化锌纳米墨水的Zeta电位；(e) ZnO-C纳米墨水的流体力学半径随老化时间的变化统计图；(f)乙醇胺的配位作用示意图；((g)~(i)) 三种氧化锌纳米粒子的TEM图像

Figure 1. Diameter of ZnO-A (a), ZnO-B (b) and ZnO-C (c) nanoinks measured through DLS; (d) Zeta potential of the ZnO nanoinks; (e) Diameter of ZnO-C nanoink during long-term storage; (f) Diagram of ethanolamine coordination; ((g)-(i)) TEM images of the ZnO nanoparticles

DLS—Dynamic light scattering; Z-average—Average hydrodynamic diameter obtained from DLS light intensity; ZnO-A—ZnO nanoparticle ink dispersed in n-butanol solvent; ZnO-B—ZnO nanoparticle ink dispersed in the mixed solvent containing 66% n-butanol and 34% ethanol; ZnO-C—Zinc oxide nanoparticle ink dispersed in mixed solvents containing 66% n-butanol and 34% ethanol, and added with 1.5 mg/mL ethanolamine

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图 2 (a)狭缝涂布印刷示意图；((b)~(d)) 三种氧化锌薄膜的SEM图像；(e)自制的36通道的紫外可见光吸收光谱仪示意图；((f)~(h)) 根据36通道吸收光谱测试薄膜397 nm处的吸收强度绘制的氧化锌薄膜的吸收强度分布图

Figure 2. (a) Schematic diagram of slot-die coating; ((b)-(d)) SEM images of three kinds of ZnO films; (e) Schematic diagram of homemade 36-channel UV-vis absorption spectrometer; ((f)-(h)) Absorption intensity distribution diagram of ZnO films based on absorption intensity at 397 nm

ETL—Electron transporting layer; AgNWs/PET—Ag nanowires/polyethylene terephthalate

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图 3 (a)流体的马兰戈尼再循环速度分解示意图；(b)三种氧化锌薄膜成膜示意图

Figure 3. (a) Diagram of Marangoni recirculation velocity decomposition of fluid; (b) Diagram of film formation of the three ZnO films

V_Ma—Loop velocity; V_Rad—Radial velocity

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图 4 (a)狭缝涂布印刷的100×100 mm²大面积ZnO-C薄膜；(b)本论文所使用的倒置柔性器件结构示意图；基于这三种氧化锌薄膜的1 cm² PM6:Y6倒置柔性有机太阳能电池最优器件的J-V曲线(c)和器件性能分布图(d)

Figure 4. (a) 100×100 mm² large-area ZnO-C film fabricated through slot-die coating; (b) Device structure of flexible 1 cm² PM6:Y6 inverted flexible organic solar cells; (c) J-V characteristics of the optimized devices; (d) Histogram of device performance

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表 1 乙醇胺(EA)添加剂含量对ZnO-C的小面积刚性器件性能影响

Table 1. Device performance of the small area rigid ZnO-C solar cells with different concentrations of ethanol amine (EA)

EA/(mg·mL⁻¹)	V_OC/V	J_SC/(mA·cm⁻²)	FF/%	Average PCE/%	Maximum PCE/%
0	0.839	23.00	70.04	13.52 ± 0.46	13.87
0.5	0.837	23.49	71.34	14.02 ± 0.29	14.23
1.0	0.836	24.41	71.90	14.68 ± 0.12	14.71
1.5	0.837	24.46	71.55	14.65 ± 0.19	14.81
2.0	0.835	24.05	71.38	14.33 ± 0.44	14.66
5.0	0.839	23.86	70.91	14.20 ± 0.46	14.59
10.0	0.798	24.28	47.52	9.20 ± 0.96	10.08
Notes: PCE—Photovoltaic conversion efficiency of the 8 individual devices; These devices with an area of 0.09 cm² had a structure of Glass/ITO/ZnO-C ETL/PM6:Y6/MoO₃/Al; V_OC—Open circuit voltage; J_SC—Short circuit current density; FF—Filling factor.

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表 2 基于不同厚度的ZnO-C狭缝涂布薄膜作电子传输层的1 cm² PM6:Y6倒置柔性有机太阳能电池性能

Table 2. Performance of 1 cm² PM6:Y6 inverted flexible organic solar cells based on ZnO-C electron transporting layers with different thicknesses

ZnO-C/(mg·mL⁻¹)	Thickness/nm	V_OC/V	J_SC/(mA·cm⁻²)	FF/%	Average PCE/%	Maximum PCE/%
20	23 ± 6.4	0.825	22.21	68.03	12.47 ± 0.19	12.66
40	43 ± 5.1	0.825	24.26	68.76	13.76 ± 0.17	13.88
60	59 ± 3.9	0.825	24.79	69.32	14.18 ± 0.14	14.38
80	86 ± 6.6	0.825	23.44	68.94	13.33 ± 0.18	13.56
Note: PCE—Photovoltaic conversion efficiency of the 9 individual devices.

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表 3 基于ZnO-A、ZnO-B和ZnO-C薄膜为电子传输层 (ETL) 的1 cm² PM6:Y6倒置柔性有机太阳能电池性能

Table 3. Performance of 1 cm² PM6:Y6 inverted flexible organic solar cells based on ZnO-A, ZnO-B, and ZnO-C electron transporting layers (ETL)

ETL	Thickness/nm	V_OC/V	J_SC/(mA·cm⁻²)	FF/%	Average PCE%	Maximum PCE/%	R_s/(Ω·cm²)	R_sh/(Ω·cm²)
ZnO-A	65 ± 6.6	0.825	22.98	67.09	12.72 ± 0.35	13.22	6.8	774.72
ZnO-B	63 ± 4.7	0.825	22.50	66.85	12.41 ± 0.30	12.41	7.9	904.08
ZnO-C	59 ± 3.9	0.825	24.79	69.32	14.18 ± 0.14	14.38	6.7	1006.36
Notes: R_s—Series resistance；R_sh—Shunt resistance.

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表 4 柔性大面积(≥1 cm²) 有机太阳能电池的进展

Table 4. A recent report of flexible large-area (≥1 cm² ) organic solar cells progress

Year	Device Structure	ETL coating method	Area/cm²	PCE/%	Ref.
2017	PES/Ag/PEI/P3HT:ICBA/CRL/PTB7:PC₇₁BM/ PEDOT:PSS/Silver grid	Spin coating	10.5	6.5	[31]
2017	PET-ITO/ZnO NPs/PTB7-Th: p-DTS(FBTTH₂)₂:PC₇₁BM/MoO_X/Ag	Spin coating	1.25	8.28	[32]
2018	ITO/ZnO NPs/PTB7-Th:ITIC/MoO₃/Ag	Spin coating	2.03	7.6	[33]
2019	PET/Ag/Cu-grid/ZnO NPs/PBDB-TF:IT-4F/MoO₃/Al	Spin coating	1	12.26	[34]
2019	PET/ITO/Sol-gel ZnO/PBDB-T:ITIC/MoO₃/Ag	Spin coating	1.04	9.77	[35]
2020	PET/AgNWs/ZnO NPs/PM6:Y6/MoO₃/Al	Spin coating	1	13.6	[27]
2020	PET silver-grid/Sol-gel ZnO/PTB7-Th:COi8DFIC:PC₇₁BM/MoO_X/Ag	Spin coating	1	12.16	[36]
2020	PET/Nabil transparent electrode/ZnO NPs/ PTB7-Th:EH-IDTBR/MoO₃/Ag	Spin coating	85	5.21	[37]
2021	ITO/PEDOT:PSS/PBDB-T:ITIC:FOIC/ZrAcac/Al	Spin coating	1.05	9.81	[38]
2021	PET/Ag grid/AgNWs:PEI-Zn/PBDB-T-2F:Y6:PC₇₁BM/MoO₃/Ag	Blade coating	54	13.2	[3]
2021	PEN/ITO/Sol-gel ZnO/BTP-eC9/MoO_X/Ag	Blade coating	1	16.71	[2]
2022	PET/Ag/Cu electrode/Amorphous ITO ZnO NPs/PM6:BTP-4Cl-12/MoO₃/Al	Spin coating	25.42	12.42	[1]
Notes: PES—Polyethersulfone; PEI—Polyethyleneimine; P3HT—Poly(3-hexylthiophene-2,5-diyl); ICBA—Indene-C₆₀ bisadduct; CRL—Charge-recombination layer; PTB7-Th—Poly[4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b;4,5-b']dithiophene-2,6-diyl-alt-(4-(2-ethylhexyl)-3-fluorothieno[3,4-b]thiophene-)-2-carboxylate-2-6-diyl)]; PC₇₁BM—[6,6]-Phenyl C₇₁ butyric acid methyl ester; PEDOT:PSS—Poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate); p-DTS(FBTTH2)₂—7,7-(4,4-Bis(2-ethylhexyl)-4H-silolo[3,2-b:4,5-b']dithiophene-2,6-diyl)bis(6-fluoro-4-(5'-hexyl-[2,2'-bithiophen]-5-yl)-benzo[c][1,2,5] thiadiazole); ITIC—3,9-Bis(2-methylene(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11-tetrakis(4hexylphenyl)-dithieno[2,3-d:2′,3′-d′]-s-indaceno[1,2-b:5,6-b′] dithiophene; IT-4F—3,9-Bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:2',3'-d']-s-indaceno[1,2-b:5,6-b'] dithiophene); PBDB-T—Poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)-benzo[1,2-b:4,5-b']dithiophene))-alt-(5,5-(1',3'-di-2-thienyl-5',7'-bis(2-ethylhexyl)benzo[1',2'-c:4',5'-c']dithiophene-4,8-dione)]; COi8DFIC—2,2'-([4,4,11,11-Tetrakis(4-hexylphenyl)-4,11-dihydrothieno4-hexylphenyl)-4,11-dihydrothieno[2',3':4,5]thieno[2,3-d]thieno[2'''',3'''':4''',5''']thieno[2''',3''':4'',5'']pyrano[2'',3'':4',5']thieno[2',3':4,5] thieno[3,2-b]pyran-2,9-diyl]bis{(Z)methylylidene[(2Z)-5,6-difluoro-3-oxo-1H-indene-2,1(3H)-diylidene]})dimalononitrile; EH-IDTBR—5,5'-[[4,4,9,9-Tetrakis(2-ethylhexyl)-4,9-dihydro-s-indaceno[1,2-b:5,6-b']dithiophene-2,7-diyl]bis(2,1,3-benzothiadiazole-7,4-diylmethylidyne)]bis[3-ethyl-2-thioxo-4-thiazolidinone]; FOIC—Three[thieno[3,2-b]thiophene]-2-(5/6-fluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)-malononitrile; BTP-4Cl-12—2,2′-((2Z,2′Z)-((12,13-bis(2-butyloctyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2″,3″:4′,5′]thieno[2′,3′:4,5]pyrrolo [3,2-g]thieno[2′,3′:4,5]thieno[3,2-b]indole-2,10-diyl)bis(methanylylidene))bis(5,6-dichloro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile.

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