Table of Content

10 July 2023, Volume 44 Issue 7

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Preface

有机太阳能电池专刊

李永舫, 陈红征, 朱晓张, 何凤

2023, 44(7):  1-2. 

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Content

Cover and Content of Chemical Journal of Chinese Universities Vol.44 No.7(2023)

2023, 44(7):  1-6. 

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Review

Research Progress of Graphdiyne-based Materials in Photovoltaic Applications

REN Yi, KAN Yuanyuan, SUN Yanna, LI Jianfeng, GAO Ke

2023, 44(7):  20220752.  doi:10.7503/cjcu20220752

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Graphdiyne， a novel carbon material with China intellectual property right， is composed of topologically ordered sp and sp² carbon atoms. It has many unique advantages such as rich carbon chemical bonds， large conjugated systems， and excellent chemical stability， showing the application potential in energy conversion and other fields. In this review， the controllable synthesis of graphdiyne is focused. Then the application based on graphdiyne in different types of solar cells is described comprehensively. Especially， the mechanism of graphdiyne materials is elucidated particularly in performance improvement. Finally， short perspectives of graphdiyne materials in the photovoltaic field are presented.



Application of 2D NMR in Organic Photovoltaics

CHEN Hongru, BAI Yang, ZHOU Qiuju, ZHANG Zhiguo

2023, 44(7):  20230104.  doi:10.7503/cjcu20230104

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Two-dimensional nuclear magnetic resonance technique（2D NMR） plays a crucial role in the structural analysis of complex organic compounds. Analyzing the correlation signals of 2D NMR spectra could help us obtain the information about intra- and inter-molecular interactions. Meanwhile， it is significant to study molecular interaction between photoactive layer materials for organic photovoltaics. Such interaction can help us not only analyze the aggregation behavior of molecules， but also understand the changes in the morphology and stability of the active layer upon the addition of a third component. In this review， we provide relevant introduction on the 2D NMR spectrum， and summarize the related works on the use of 2D NMR in the analyzing the interaction between molecules in organic solar cells. Finally， It offers a perspective on the future development in this technique.



Research Progress of Layer-by-layer Deposited Organic Solar Cells

ZHAO Mingxin, YAO Zhigang, LIU Zhongyuan, XU Wenjing, MA Xiaoling, ZHANG Fujun

2023, 44(7):  20230120.  doi:10.7503/cjcu20230120

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In the recent 30 years， donor and acceptor materials mixed bulk heterojunction（BHJ） are considered to be the most ideal device structure of organic photovoltaics（OPVs）. The efficiency of exciton dissociation and charge transport can be improved by optimizing the donor-acceptor interpenetrating network structure in the active layer， which should be an effective way to improve the performance of BHJ OPVs. The layer-by-layer（LbL） OPVs are constructed by sequentially depositing donor and acceptor， which have been developed rapidly in recent years. The power conversion efficiency（PCE） of LbL OPVs can be comparable with that of BHJ OPVs， indicating that many scientific issues need to be further studied in OPVs. This review summarizes the representative achievements of LbL OPVs from the working mechanism， optimization strategy and large-area production potential. The key roles of additives， annealing treatment and multi-component strategy in improving device performance are emphasized. The problems existing in LbL OPVs are discussed， and the future prospects of LbL OPVs are outlooked.



Recent Progress in Non-fused Ring Small-molecule Acceptor Materials

SUN Heng, ZHANG Pengyu, ZHANG Yingnan, ZHAN Chuanlang

2023, 44(7):  20230076.  doi:10.7503/cjcu20230076

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The invention of non-fullerene acceptors with rigid and fused ring structures has pushed a rapid progress in the field of organic solar cells. The power conversion efficiencies（PCEs） have exceeded 19%. Compared with the fused ring structures， the non-fused ring acceptors have recently received increasing attention due to their relatively simple structures and synthesis. Since 2017， the molecular library of non-fused ring acceptors has extended up to more than 100 molecules and the PCEs have rapidly increased from the initial 4% to the recent 16%. In this review， we classified these molecules into fully non-fused ring acceptors and A-D-C _n -D-A type non-fused ring acceptors， according to the non-fused ring backbone structural features. We correlate the molecular structures and the optical， electrochemical and photovoltaic properties from the aspects of non-fused ring backbone structures and side chain engineering. In particular， we focus on that the non-fused ring backbone structures， intramolecular non-covalent interactions and side chain engineering finely tune the materials’ energy levels and bandgaps and photovoltaic performance. We also give suggestions to overcome the factors that limit the increase of solar cell performance.



Advances in Pseudo-planar Heterojunction Organic Photovoltaic Devices

WEN Min, LI Haojie, LI Junliang, LIU Siqi, HU Xiaotian, CHEN Yiwang

2023, 44(7):  20230174.  doi:10.7503/cjcu20230174

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Organic solar cells（OSCs） have been the top research hotspot in the field of solar cells due to their advantages such as light weight， flexibility， and ease of large area preparation. Currently， the power conversion efficiency（PCE） of single junction OSCs has exceeded 19%. In-depth study of active layer film formation kinetics and thermodynamics has significant implications for enhancing the performance of organic solar cells. Meanwhile， the development of large-area printing preparation technology is beneficial to promoting the commercialization of OSCs. This review systematically summarizes the representative results in OSCs based on pseudo-planar heterojunction（PPHJ） structures， focuses on the research progress of interface engineering modulation and preparation process optimization in organic photovoltaic devices， and provides an outlook on the future development of high-performance large-area OSCs.



Asymmetric Fused-ring Photovoltaic Electron Acceptors

SI Wenqin, LI Tengfei, LIN Yuze

2023, 44(7):  20230149.  doi:10.7503/cjcu20230149

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Benefiting from the development of fused-ring electron acceptors（FREAs）， power conversion efficiencies of organic solar cells have rapidly increased from 12% for the fullerene era to 20% for the non-fullerene era. The asymmetric molecular design strategy plays an important role in the enhancement of photovoltaic performance. In this paper， we review the research progress of asymmetric FREAs according to the following three kinds of molecular design strategies： the asymmetric fused-ring backbone， asymmetric end groups and asymmetric side chains， discuss the structure-property relationship， and finally provide an outlook on the future development of asymmetric FREAs.



Article

Effects of Different Halogenated End-groups Non-fullerene Acceptors on the Organic Solar Cells

GUO Yuntong, CHEN Zhenyu, GE Ziyi

2023, 44(7):  20230084.  doi:10.7503/cjcu20230084

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The end-group halogenation of non-fullerene acceptors（NFAs） is an effective method to fabricate high- performance NFAs organic solar cells（OSCs）. Here in， three NFAs， BTP-SSe-F， BTP-SSe-Cl and BTP-SSe-Br， were synthesized. They had different halogenated end groups， IC-2F， IC-2Cl and IC-2Br， respectively. The photophysical properties， electrochemical properties， organic photovoltaic properties and active layer morphology of the three NFAs were tested and analyzed. It was found that fluorinated NFAs had lower energy levels than chlorinated and brominated NFAs. The UV-visible absorption spectra of the three NFAs all showed red-shifting， and the intermolecular force of BTP-SSe-F was stronger. BTP-SSe-F had better electron and hole mobility and more balanced electron and hole mobility. Compared with BTP-SSe-Cl and BTP-SSe-Br， BTP-SSe-F blends had more suitable roughness， better phase separation size and stronger π⁃π packing. When PM6 was used as the donor material， the BTP-SSe-F based optoelectronic devices exhibited the highest power conversion efficiency（PCE=16.53%）， the highest current density（J_SC=28.17 mA/cm²） and the highest filling factor（FF=74.11%）. These results indicate that different halogenated end-group NFAs have great influence on the photoelectric performance of OSCs， and the fluorination of end-group can be very effective in constructing high-performance photovoltaic materials.



High-performance Organic Solar Cells Based on Trifluorobenzoic Acid Self-assembled Anode Interfacial Layers

HE Wei, CHEN Fei, LI Hongxiang, WANG Jiayu, QIN Jiaqiang, CUI Ningbo, YAN Cenqi, CHENG Pei

2023, 44(7):  20230161.  doi:10.7503/cjcu20230161

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A self-assembled anode interfacial layer was constructed using 3，4，5-trifluorobenzoic acid（3FBA）. Compared with traditional anode interfacial layers including PEDOT∶PSS and MoO₃， the 3FBA interfacial layer has higher transmittance and better hydrophobicity. Organic solar cells based on the 3FBA anode interfacial layers achieved high short-circuit current density of 26.86 mA/cm² and power conversion efficiency（PCE） of 18.16%， significantly excelling devices based on PEDOT∶PSS（26.28 mA/cm²， 17.62%） and devices based on MoO₃（26.00 mA/cm²， 17.15%）. This work provides a new idea for the design and construction of the anode interfacial layers of organic solar cells.



Synthesis of Difluorodithienophenazine Based Conjugated Polymers and Their Organic Photovoltaic Performance

ZHANG Zesheng, DENG Yuxin, KONG Lingchen, LUO Mei, WANG Xinkang, ZHANG Lianjie, CHEN Junwu

2023, 44(7):  20230148.  doi:10.7503/cjcu20230148

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Designing electron-deficient unit based on fused ring is an effective strategy for constructing high-performance conjugated copolymers. In this work， a new electron-deficient monomer（DTPZ） with 9，10-difluorodithienophenazine as the core was synthesized， and two new polymers PB-DTPZ and PFB-DTPZ were prepared. The photophysical properties， electrochemical properties， and organic photovoltaic performance of the two polymers as well as their active layer morphologies were studied and analyzed. Polymers PB-DTPZ and PFB-DTPZ possess optical band gaps of 1.70 and 1.68 eV， respectively， showing red-shifted absorption spectra compared with common wide band gap polymers. The PB-DTPZ and PFB-DTPZ also show low-lying HOMO energy levels of ‒5.51 and ‒5.68 eV， respectively， suggesting the electron-deficient feature of DTPZ. Thanks to the more matched HOMO energy level to Y6 acceptor， the PB-DTPZ∶Y6-based binary polymer solar cell can achieve a power conversion efficiency（PCE） of 12.13%， which is higher than that（10.4%） of the PFB-DTPZ∶Y6-based binary device. Due to the deeper HOMO levels and complementary absorption spectra of PB-DTPZ and PFB-DTPZ， the addition of the two polymers as the third component to the PM6∶Y6 system can further improve the PCE， and the resulting ternary devices can deliver PCEs of 17.08% and 16.99%， respectively.



Effect of Alkyl-chain Branching Position on Molecular Aggregation of All-fused-ring Molecules

ZHANG Yongqian, ZHU Xiaoyu, MIAO Junhui, LIU Jun, WANG Lixiang

2023, 44(7):  20230068.  doi:10.7503/cjcu20230068

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All-fused-ring molecules are a novel type of electron acceptor materials with excellent intrinsic stability for organic solar cell（OSC） applications. In this work， we developed two all-fused-ring small molecular acceptors， FM5 and FM6， with different branching positions of alkyl chains on the pyrrole motif. The effects of branching points of the alkyl chains on optical and electronic properties， molecular stacking of the molecules were investigated. Compared with FM5 with 2nd-position branched alkyl chains， FM6 with 3rd-position branched alkyl chains exhibits the blue-shifted absorption and higher crystallinity. Due to the large steric hindrance caused by alkyl chains at 2nd branching sites， FM5 exhibits appropriate molecular aggregation and thus favorable film morphology in the blend film. Due to the suitable blend film morphology， the OSC device using FM5 as electron acceptor exhibits a power conversion efficiency（PCE） of 9.03%， which is higher than that of FM6（6.67%）. These results demonstrate that the side chain engineering is an effective strategy for tuning the molecular aggregation， crystalline and blend film morphology for all-fused-ring molecules.



Predict Efficiency of Organic Solar Cell with Low Generalization Error Based on Molecular Property and Device Fabrication

ZHANG Yan, JIANG Xingjian, LIU Ming, ZHENG Zhi, ZHANG Yong

2023, 44(7):  20230165.  doi:10.7503/cjcu20230165

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Organic solar cells（OSCs） have been a very active research field in recent years. There are two main optimization strategies which are novel donor or acceptor and device fabrication. Due to the huge number of influencing factors and their complicated internal interaction mechanism， it’s almost impossible to build a complete theory to describe and analyze device power conversion efficiency（PCE）. However， machine learning may be a feasible answer. In this research， molecular properties and device fabrication are combined to build dataset. To decrease generalization error， models are developed by random forest， support vector machine and multiple perceptron. Random forest shows the best performance and is determined to the final algorithm. After further optimization， the test set R² average of 100 different random state converges on 0.9012 and the quantitative results of feature importance are given. The dataset plays a critical role in the performance of machine learning model. The results indicate the feasibility of applying results given by machine learning models as references for experiments and analysis.



End-capped Polymer Donors for Highly-efficient Organic Solar Cells

ZHANG Youhui, YANG Na, DUAN Na, CHENG Yujun, YOU Shiyong, WU Feiyan, CHEN Lie

2023, 44(7):  20230169.  doi:10.7503/cjcu20230169

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End-capping engineering is a very simple and convenient strategy for polymer modification， whereas its application in high performance non-fullerene organic solar cells is still limited. In this paper， three novel fully end-capped donors PM6-T-EH， PM6-2T-EH and PM6-3T-EH were prepared by capped with 2-（2-ethylhexyl）-thiophene（T-EH）， 5-（2-ethylhexyl）-2，2′-bithiophene（2T-EH）， and 5-（2-ethylhexyl）-2，2′∶5′，2′′-terthiophene（3T-EH）， respectively. Compared with pristine polymer donors PM6（15.40%）， end-capped polymers PM6-T-EH， PM6-2T-EH， PM6-3T-EH blended with Y6 achieved the power conversion efficiencies（PCE） of 16.66%， 15.54% and 13.50%， respectively. It is shown that the alkyl monothiophene end-capped polymer can reduce the carrier traps， optimize the morphology and improve the charge transport in the active layer， thus enhance the overall PCE. The gradually decreased device performance along with the increase of thiophene units in end-capping groups， is mainly attributed to the deteriorated morphology of active layer， resulting from the bulky conjugated chains of the end- capping groups. Further optimizing the active layer， the device based on PM6-T-EH∶BTP-eC9 achieved a highe efficiency of 18.02%.



Non-fullerene Acceptors with Germanium as Bridge Atom and Their Applications in Organic Solar Cells

ZHANG Yi, SHAN Tong, WANG Yan, ZHONG Hongliang

2023, 44(7):  20230050.  doi:10.7503/cjcu20230050

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Organic photovoltaic materials are composed of conjugated backbone and alkyl sidechain， which bear the functions of photo-sensitivity and solubilization. The bridge atom which is used to connect the backbone and the sidechain is rarely studied， although it plays a key role in determining molecular geometry and optoelectronic property. Herein， this work developed acceptor materials with germanium bridge and investigates the structure-property relationship. Compared with the traditional C—C bond， the longer C—Ge bond affected the planarity of the conjugated backbone as well as the distance between the backbone and the sidechain. Moreover， the fluorinated terminal was introduced into the acceptor GD4F-C8 to tune molecular geometry and packing order by non-covalent bond interaction which was induced by the fluorine atoms. As a result， GD4F-C8 has a broad absorption spectrum and suitable energy levels. More importantly， the compatibility of GD4F-C8 and the polymer donor PM6 is improved to deliver an active layer with favorable morphology. Eventually， organic solar cells based on PM6∶GD4F-C8 achieves a power conversion efficiency of 8.74%， demonstrating the potential of germanium-containing materials in organic solar cells and providing a new insight for acceptor design.



All-small-molecule Organic Solar Cells with Enhanced Efficiency and Stability Enabled by Polymer Additive as a Morphology Modulator

SHI Yu, ZHANG Liu, GUO Xia, WANG Yang, XIAO Haiqin, FANG Jin, ZHOU Yi, ZHANG Maojie

2023, 44(7):  20230047.  doi:10.7503/cjcu20230047

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For all-small-molecule organic solar cells（ASM-OSCs）， modulating the morphology of active layer has been a challenging and urgent issue to achieve high efficiency and stablity. In this work， a polymer donor PM7 as a morphology modulator was incorporated to a BTTzR∶Y6 system to fabricate ternary ASM-OSCs. A small amount of PM7 could promote more favourable nanostructure and ordered molecular packing in the blend film， resulting in more efficient excition dissiociation and charge carrier transport in the device. As a result， the optimal ternary devices exhibited a significantly improved power conversion efficiency（PCE） of 16.0% with simultaneously enhanced short circuit current（J_SC） and fill factor（FF） compared to the binary devices with a PCE of 13.9%. Notably， after being heated at 85 ℃ for 2200 min， the ternary devices still retained 79% of its initial PCE， whereas the binary devices showed larger decay to 43% in the same duration. The results demonstrated that adding the polymer additive can effectively modulate the blend morphology for highly efficient and stable ASM-OSCs.



Understanding the Mixing Phase Structure in Multi-length-scale Morphology to Arrest High-performance Photovoltaic Devices

ZHANG Ming, ZHONG Wenkai, QIAN Shiyun, LYU Bosai, ZHOU Guanqing, XUE Xiaonan, ZHOU Zichun, SHI Zhiwen, ZHU Lei, ZHANG Yongming, LIU Feng

2023, 44(7):  20230147.  doi:10.7503/cjcu20230147

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The properties of the mixing phase are investigated in detail by introducing PC₇₁BM into two typical organic photovoltaic blends J51∶N2200 and PM6∶Y6. It is found that the process of exciton dissociation and carrier transport in the mixing zone play a key role in determining the power conversion efficiency. In J51∶N2200∶PC₇₁BM blend， the aggregation of PC₇₁BM in the mixing zone brings in energetic barrier to inhibit the hole transfer process. In the meanwhile， the enlarged intervals in-between the double fibril network limit the effective diffusion of the split electrons and holes in the mixing zone， leading to large recombination and energy loss. While in PM6∶Y6∶PC₇₁BM blend， the introduced PC₇₁BM could homogeneously distribute in the amorphous zone， mixing well with PM6 and Y6 molecules. Meanwhile， the addition of PC₇₁BM does not perturb the hole transfer from Y6 to PM6. Such a morphology is advantageous where electrons and holes generated at abundant donor/acceptor interface could diffuse out rapidly， and transport in the crystalline pathway towards the corresponding electrodes. Such results reveal the importance of manipulating the mixing phase structure in the multi-length-scale morphology， of high demand towards 20% efficiency in the next episode organic solar cell（OSC） development.



Double-cable Conjugated Polymers with Rigid Linkers for Single-component Organic Solar Cells

FANG Haisheng, LIANG Shijie, XIAO Chengyi, XIA Dongdong, LI Weiwei

2023, 44(7):  20230146.  doi:10.7503/cjcu20230146

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Two novel double-cable conjugated polymers， poly［2-（4-｛3，3′-didodecyl-5′-［4-（1-｛4-［5-（2-ethylhexyl）thiophen-2-yl］-8-［5-（heptan-3-yl）thiophen-2-yl］benzo［1，2-b∶4，5-b′］dithiophen-2-yl｝-4，6-dioxo-4H-thieno ［3，4-c］pyrrol-5（6H）-yl）phenyl］-［2，2′-bithiophen］-5-yl｝phenyl）-9-（tricosan-12-yl）anthra［2，1，9-def∶6，5，10-d′e′f′］diisoquinoline-1，3，8，10（2H，9H）-tetraone）］（FLP7） and poly［2-（4-｛4，4′-didodecyl-5′-［4-（1-｛4-［5-（2-ethylhexyl）thiophen-2-yl］-8-［5-（heptan-3-yl）thiophen-2-yl］benzo［1，2-b∶4，5-b′］dithiophen-2-yl｝-4，6-dioxo-4H-thieno［3，4-c］pyrrol-5（6H）-yl）phenyl］-［2，2′-bithiophen］-5-yl｝phenyl）-9-（tricosan-12-yl）anthra［2，1，9-def∶6，5，10-d′e′f′］diisoquinoline-1，3，8，10（2H，9H）-tetraone］（FLP8）， have been developed with bithiophene-based rigid linkers. These polymers were synthesized by adopting a thiophenedicarboximide（TPD） donor backbone and perylene biimide（PBI） acceptor side units. By adjusting the position of alkyl chains on the rigid linkers from external to interior， the self-aggregation capacity， film morphology and photoelectric conversion efficiency of the polymers were improved. Finally， the FLP7 polymer demonstrated superior photoelectric performance parameters as compared to the FLP8 polymer and achieved a power conversion efficiency of 1.59%.



Benzotriazole-based Polymer Acceptors with Precise Structures for All-polymer Solar Cells

ZHANG Yue, WU Baoqi, TIAN Shizeng, HUANG Xuelong, LI Junyu, PAN Langheng, HUANG Fei, CAO Yong, DUAN Chunhui

2023, 44(7):  20230129.  doi:10.7503/cjcu20230129

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In this contribution， two polymer acceptors（PT1-γ and PT1-δ） based on benzotriazole（BTz） were designed and synthesized by regulating the polymerization sites. The effects of polymerization sites on the optical absorption， electrochemical energy levels， charge carrier mobility， and device performance of all-polymer solar cells （all-PSCs） were comprehensively investigated. Compared to PT1-δ， the polymer PT1-γ exhibited narrower optical bandgap and higher electron mobility. As a result， the PT1-γ-based all-PSC achieved a promising power conversion efficiency（PCE） of 11.92% with an open-circuit voltage of 0.89 V， a high short-circuit current density of 21.25 mA/cm²， and a fill factor of 0.63 when blended with PBDB-T， which is higher than 9.68% of the all-PSC based on PT1-δ. This work demonstrates that the polymerization site has a very significant effect on the optoelectronic properties of benzotriazole-based polymer acceptors. Therefore， regulating the polymerization sites of monomers is an effective design strategy for the development of high-performance polymer acceptors.



Pre-aggregation Manipulation of Polymer Donor Using Guest Plasticizers for Developing Nonhalogenated Green Solvent Processed High-performance Organic Solar Cells

CHEN Haiyang, LI Xinqi, DING Junyuan, HUANG Yuting, LI Yaowen

2023, 44(7):  20230128.  doi:10.7503/cjcu20230128

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Recent advances in non-fullerene acceptors like Y6 have pushed the power conversion efficiencies（PCEs） of organic solar cells（OSCs） above 19%. However， the harsh fabrication conditions， such as the use of the highly volatile chloroform solvent， are not suitable for large-area printing technologies and environmental standards. Here， a third component（guest） BTP-3Si-4F is designed and synthesized with siloxane repeating units in side chains. The guest BTP-3Si-4F could act as a plasticizer， which inhibits the pre-aggregation behavior of PM6 in nonhalo-genated（toluene） solution and enables the active layer to form a morphology with suitable phase separation scale. Therefore， BTP-3Si-4F blended with PM6∶Y6 and PM6∶BTP-eC9 deliver the highest PCEs of 16.92% and 17.64%， respectively. The results demonstrate controlling the pre-aggregation behavior of donor via guest molecules is an effective and universal way to achieve efficient OSCs in non-halogenated solution.



Infrared Nanosecond Laser Assisted Preparation of Large-area Organic Photovoltaic Module

WU Jiang, LI Youzhan, LIU He, FU Yingying, XIE Zhiyuan

2023, 44(7):  20230078.  doi:10.7503/cjcu20230078

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The development of new active layer materials and the precise regulation of active layer morphologies have greatly facilitated the advances of organic photovoltaic cells（OPVs） and have recently enabled the power conversion efficiency（PCE） of small-area OPVs to exceed 19% in the laboratory. However， the preparation of efficient and stable large-area OPV modules still faces challenges for its industrialization in the future and draws great attention in recent years. Herein， high-performance large-area OPV modules were fabricated by using an infrared nanosecond laser to achieve accurate ablation and patterning of the individual functional layers. Compared to the commonly used femtosecond lasers for the fabrication of OPV modules， infrared nanosecond laser-assisted preparation of OPV modules is promising to reduce the manufacturing cost. The laser processing for the ablation of the individual layers was investigated and the damage to indium tin oxide（ITO） transparent electrode was effectively reduced by precise adjustment of laser parameters. The ablation of intermediate organic layers with weak infrared absorption was realized with the help of thermal effect coming from the under ITO layer. The large-area OPV module with an effective area of 28 cm² and a high geometric fill factor of more than 93% was fabricated and an overall PCE of 14.33% was achieved. The demonstrated preparation of large-area high-performance OPV module via ablation of infrared nanosecond laser holds potential to advance the development of large-area OPV devices and paves the way for its commercialization in the future.



Cross-linking PEDOT∶F Hole-transporting Layer to Enhance Photovoltaic Performance of Flexible Organic Solar Cells

WEI Wanxia, ZHOU Xianmin, DONG Xinyun, LIU Tiefeng, XIE Cong, CHENG Jingyu, CHEN Jianping, LU Xin, FENG Kai, ZHOU Yinhua

2023, 44(7):  20230069.  doi:10.7503/cjcu20230069

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Silver nanowires（AgNWs） are important printable top electrodes in flexible organic solar cells（OSCs）. However， when fabricating AgNWs from ethanol solution， it could cause damage on the hole-transporting layer below due to washing out. In this work， we propose a cross-linking strategy on the hole-transporting layer of poly（3，4-ethylenedioxythiophene）∶perfluorinated sulfonic acid ionomer（PEDOT∶F） to improve its alcohol resistance. By introducing a cross-linker of poly（ethylene glycol）diglycidyl ether（PEGDE）， PEDOT：F was successfully cross-linked. Based on the cross-linked PEDOT∶F hole-transporting layer， small-area flexible OSCs（0.041 cm²） showed power conversion efficiency of 14.86%. Flexible organic solar module（21.18 cm²） was then fabricated and an efficiency of 12.38% was achieved.