共查询到20条相似文献,搜索用时 15 毫秒
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Hao Wu Haijun Fan Wuyue Liu Shanshan Chen Changduk Yang Long Ye Harald Ade Xiaozhang Zhu 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(44)
Small molecule solar cells (SMSCs) lag a long way behind polymer solar cells. A key limit is the less controllable morphology of small molecule materials, which can be aggravated when incorporating anisotropic nonfullerene acceptors. To fine‐tune the blending morphology within SMSCs, a π‐conjunction curtailing design is applied, which produces a efficient benzodithionopyran‐cored molecular acceptor for nonfullerene SMSCs (NF‐SMSCs). When blended with a molecular donor BDT3TR‐SF to fabricate NF‐SMSCs, the π‐conjunction curtailed molecular acceptor NBDTP‐M obtains an optimal power conversion efficiency (PCE) of up to 10.23%, which is much higher than that of NBDTTP‐M of longer π‐conjunction. It retains 93% of the PCE of devices fabricated in a glove box when all spin‐coating and post‐treating procedures are conducted in ambient air with relative humidity of 25%, which suggests the good air‐processing capability of π‐conjunction curtailed molecules. Detailed X‐ray scattering investigations indicate that the BDT3TR‐SF:NBDTP‐M blend exhibits a blend morphology featuring fine interpenetrating networks with smaller domains and higher phase purity, which results in more efficient charge generation, more balanced charge transport, and less recombination compared to the low‐performance BDT3TR‐SF:NBDTTP‐M blend. This work provides a guideline for molecular acceptors' design toward efficient, low‐cost, air‐processed NF‐SMSCs. 相似文献
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Hao Wu Haijun Fan Shengjie Xu Long Ye Yuan Guo Yuanping Yi Harald Ade Xiaozhang Zhu 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(1)
Nonfullerene polymer solar cells develop quickly. However, nonfullerene small‐molecule solar cells (NF‐SMSCs) still show relatively inferior performance, attributing to the lack of comprehensive understanding of the structure–performance relationship. To address this issue, two isomeric small‐molecule acceptors, NBDTP‐Fout and NBDTP‐Fin, with varied oxygen position in the benzodi(thienopyran) (BDTP) core are designed and synthesized. When blended with molecular donor BDT3TR‐SF, devices based on the two isomeric acceptors show disparate photovoltaic performance. Fabricated with an eco‐friendly processing solvent (tetrahydrofuran), the BDT3TR‐SF:NBDTP‐Fout blend delivers a high power conversion efficiency of 11.2%, ranked to the top values reported to date, while the BDT3TR‐SF:NBDTP‐Fin blend almost shows no photovoltaic response (0.02%). With detailed investigations on inherent optoelectronic processes as well as morphological evolution, this performance disparity is correlated to the interfacial tension of the two combinations and concludes that proper interfacial tension is a key factor for effective phase separation, optimal blend morphology, and superior performance, which can be achieved by the “isomerization” design on molecular acceptors. This work reveals the importance of modulating the materials miscibility by interfacial‐tension‐oriented molecular design, which provides a general guideline toward efficient NF‐SMSCs. 相似文献
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Asymmetrical Ladder‐Type Donor‐Induced Polar Small Molecule Acceptor to Promote Fill Factors Approaching 77% for High‐Performance Nonfullerene Polymer Solar Cells 下载免费PDF全文
Wei Gao Miao Zhang Tao Liu Ruijie Ming Qiaoshi An Kailong Wu Dongjun Xie Zhenghui Luo Cheng Zhong Feng Liu Fujun Zhang He Yan Chuluo Yang 《Advanced materials (Deerfield Beach, Fla.)》2018,30(26)
In this work, an effectual strategy of constructing polar small molecule acceptors (SMAs) to promote fill factor (FF) of nonfullerene polymer solar cells (PSCs) is first reported. Three asymmetrical SMAs of IDT6CN , IDT6CN‐Th , and IDT6CN‐M , which own large dipole moments, are designed and synthesized. The PSCs based on three polar SMAs exhibit apparently higher FFs compared with their symmetrical analogues. The asymmetrical design strategy accompanied with side chain and end group engineering makes IDT6CN‐Th ‐ and IDT6CN‐M ‐based nonfullerene PSCs achieve high power conversion efficiency with FFs approaching 77%. 相似文献
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Small‐Molecule Solar Cells with Simultaneously Enhanced Short‐Circuit Current and Fill Factor to Achieve 11% Efficiency 下载免费PDF全文
Li Nian Ke Gao Yufeng Jiang Qikun Rong Xiaowen Hu Dong Yuan Feng Liu Xiaobin Peng Thomas P. Russell Guofu Zhou 《Advanced materials (Deerfield Beach, Fla.)》2017,29(29)
High‐efficiency small‐molecule‐based organic photovoltaics (SM‐OPVs) using two electron donors (p ‐DTS(FBTTh2)2 and ZnP) with distinctively different absorption and structural features are reported. Such a combination works well and synergically improves device short‐circuit current density (J sc) to 17.99 mA cm?2 and fill factor (FF) to 77.19%, yielding a milestone efficiency of 11%. To the best of our knowledge, this is the highest power conversion efficiency reported for SM‐OPVs to date and the first time to combine high J sc over 17 mA cm?2 and high FF over 77% into one SM‐OPV. The strategy of using multicomponent materials, with a selecting role of balancing varied electronic and structural necessities can be an important route to further developing higher performance devices. This development is important, which broadens the dimension and versatility of existing materials without much chemistry input. 相似文献
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Efficient Semitransparent Solar Cells with High NIR Responsiveness Enabled by a Small‐Bandgap Electron Acceptor 下载免费PDF全文
Feng Liu Zichun Zhou Cheng Zhang Jianyun Zhang Qin Hu Thomas Vergote Feng Liu Thomas P. Russell Xiaozhang Zhu 《Advanced materials (Deerfield Beach, Fla.)》2017,29(21)
Inspired by the remarkable promotion of power conversion efficiency (PCE), commercial applications of organic photovoltaics (OPVs) can be foreseen in near future. One of the most promising applications is semitransparent (ST) solar cells that can be utilized in value‐added applications such as energy‐harvesting windows. However, the single‐junction STOPVs utilizing fullerene acceptors show relatively low PCEs of 4%–6% due to the limited sunlight absorption because it is a dilemma that more photons need to be harvested in UV–vis–near‐infrared (NIR) region to generate high photocurrent, which leads to the significant reduction of device transparency. This study describes the development of a new small‐bandgap electron‐acceptor material ATT‐2, which shows a strong NIR absorption between 600 and 940 nm with an E gopt of 1.32 eV. By combining with PTB7‐Th, the as‐cast OPVs yield PCEs of up to 9.58% with a fill factor of 0.63, an open‐circuit voltage of 0.73 V, and a very high short‐circuit current of 20.75 mA cm?2. Owing to the favorable complementary absorption of low‐bangap PTB7‐Th and small‐bandgap ATT‐2 in NIR region, the proof‐of‐concept STOPVs show the highest PCE of 7.7% so far reported for single‐junction STOPVs with a high transparency of 37%. 相似文献
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Small‐Bandgap Polymer Solar Cells with Unprecedented Short‐Circuit Current Density and High Fill Factor 下载免费PDF全文
Hyosung Choi Seo‐Jin Ko Taehyo Kim Pierre‐Olivier Morin Bright Walker Byoung Hoon Lee Mario Leclerc Jin Young Kim Alan J. Heeger 《Advanced materials (Deerfield Beach, Fla.)》2015,27(21):3318-3324
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Fine‐Tuning the Energy Levels of a Nonfullerene Small‐Molecule Acceptor to Achieve a High Short‐Circuit Current and a Power Conversion Efficiency over 12% in Organic Solar Cells 下载免费PDF全文
Bin Kan Jiangbin Zhang Feng Liu Xiangjian Wan Chenxi Li Xin Ke Yunchuang Wang Huanran Feng Yamin Zhang Guankui Long Richard H. Friend Artem A. Bakulin Yongsheng Chen 《Advanced materials (Deerfield Beach, Fla.)》2018,30(3)
Organic solar cell optimization requires careful balancing of current–voltage output of the materials system. Here, such optimization using ultrafast spectroscopy as a tool to optimize the material bandgap without altering ultrafast photophysics is reported. A new acceptor–donor–acceptor (A–D–A)‐type small‐molecule acceptor NCBDT is designed by modification of the D and A units of NFBDT. Compared to NFBDT, NCBDT exhibits upshifted highest occupied molecular orbital (HOMO) energy level mainly due to the additional octyl on the D unit and downshifted lowest unoccupied molecular orbital (LUMO) energy level due to the fluorination of A units. NCBDT has a low optical bandgap of 1.45 eV which extends the absorption range toward near‐IR region, down to ≈860 nm. However, the 60 meV lowered LUMO level of NCBDT hardly changes the Voc level, and the elevation of the NCBDT HOMO does not have a substantial influence on the photophysics of the materials. Thus, for both NCBDT‐ and NFBDT‐based systems, an unusually slow (≈400 ps) but ultimately efficient charge generation mediated by interfacial charge‐pair states is observed, followed by effective charge extraction. As a result, the PBDB‐T:NCBDT devices demonstrate an impressive power conversion efficiency over 12%—among the best for solution‐processed organic solar cells. 相似文献
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Hao Zhang Xiaohui Wang Liyan Yang Shaoqing Zhang Yun Zhang Chang He Wei Ma Jianhui Hou 《Advanced materials (Deerfield Beach, Fla.)》2017,29(42)
An all‐small‐molecule ternary solar cell is achieved with a power conversion efficiency of 10.48% by incorporating phenyl‐C71‐butyric‐acid‐methyl ester (PC71BM) into a nonfullerene binary system. The addition of PC71BM is found to modulate the film morphology by improving the domain purity and decreasing the domain size. This modulation facilitates charge generation and suppresses charge recombination, as manifested by the significantly enhanced short‐circuit current density and fill factor. The results correlate the domain characteristics with the device performance and offer new insight from the perspective of morphology modulation for constructing efficient ternary devices. 相似文献
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Fine‐Tuning of Molecular Packing and Energy Level through Methyl Substitution Enabling Excellent Small Molecule Acceptors for Nonfullerene Polymer Solar Cells with Efficiency up to 12.54% 下载免费PDF全文
Zhenghui Luo Haijun Bin Tao Liu Zhi‐Guo Zhang Yankang Yang Cheng Zhong Beibei Qiu Guanghao Li Wei Gao Dongjun Xie Kailong Wu Yanming Sun Feng Liu Yongfang Li Chuluo Yang 《Advanced materials (Deerfield Beach, Fla.)》2018,30(9)
A novel small molecule acceptor MeIC with a methylated end‐capping group is developed. Compared to unmethylated counterparts (ITCPTC), MeIC exhibits a higher lowest unoccupied molecular orbital (LUMO) level value, tighter molecular packing, better crystallites quality, and stronger absorption in the range of 520–740 nm. The MeIC‐based polymer solar cells (PSCs) with J71 as donor, achieve high power conversion efficiency (PCE), up to 12.54% with a short‐circuit current (JSC) of 18.41 mA cm?2, significantly higher than that of the device based on J71:ITCPTC (11.63% with a JSC of 17.52 mA cm?2). The higher JSC of the PSC based on J71:MeIC can be attributed to more balanced μh/μe, higher charge dissociation and charge collection efficiency, better molecular packing, and more proper phase separation features as indicated by grazing incident X‐ray diffraction and resonant soft X‐ray scattering results. It is worth mentioning that the as‐cast PSCs based on MeIC also yield a high PCE of 11.26%, which is among the highest value for the as‐cast nonfullerene PSCs so far. Such a small modification that leads to so significant an improvement of the photovoltaic performance is a quite exciting finding, shining a light on the molecular design of the nonfullerene acceptors. 相似文献
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Ke Gao Sae Byeok Jo Xueliang Shi Li Nian Ming Zhang Yuanyuan Kan Francis Lin Bin Kan Bo Xu Qikun Rong Lingling Shui Feng Liu Xiaobin Peng Guofu Zhou Yong Cao Alex K.‐Y. Jen 《Advanced materials (Deerfield Beach, Fla.)》2019,31(12)
In this paper, two near‐infrared absorbing molecules are successfully incorporated into nonfullerene‐based small‐molecule organic solar cells (NFSM‐OSCs) to achieve a very high power conversion efficiency (PCE) of 12.08%. This is achieved by tuning the sequentially evolved crystalline morphology through combined solvent additive and solvent vapor annealing, which mainly work on ZnP‐TBO and 6TIC, respectively. It not only helps improve the crystallinity of the ZnP‐TBO and 6TIC blend, but also forms multilength scale morphology to enhance charge mobility and charge extraction. Moreover, it simultaneously reduces the nongeminate recombination by effective charge delocalization. The resultant device performance shows remarkably enhanced fill factor and Jsc. These result in a very respectable PCE, which is the highest among all NFSM‐OSCs and all small‐molecule binary solar cells reported so far. 相似文献
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Improved Performance of All‐Polymer Solar Cells Enabled by Naphthodiperylenetetraimide‐Based Polymer Acceptor 下载免费PDF全文
Yikun Guo Yunke Li Omar Awartani Han Han Jingbo Zhao Harald Ade He Yan Dahui Zhao 《Advanced materials (Deerfield Beach, Fla.)》2017,29(26)
A new polymer acceptor, naphthodiperylenetetraimide‐vinylene (NDP‐V), featuring a backbone of altenating naphthodiperylenetetraimide and vinylene units is designed and applied in all‐polymer solar cells (all‐PSCs). With this polymer acceptor, a new record power‐conversion efficiencies (PCE) of 8.59% has been achieved for all‐PSCs. The design principle of NDP‐V is to reduce the conformational disorder in the backbone of a previously developed high‐performance acceptor, PDI‐V, a perylenediimide‐vinylene polymer. The chemical modifications result in favorable changes to the molecular packing behaviors of the acceptor and improved morphology of the donor–acceptor (PTB7‐Th:NDP‐V) blend, which is evidenced by the enhanced hole and electron transport abilities of the active layer. Moreover, the stronger absorption of NDP‐V in the shorter‐wavelength range offers a better complement to the donor. All these factors contribute to a short‐circuit current density (J sc) of 17.07 mA cm?2. With a fill factor (FF) of 0.67, an average PCE of 8.48% is obtained, representing the highest value thus far reported for all‐PSCs. 相似文献
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Qihui Yue Hao Wu Zichun Zhou Ming Zhang Feng Liu Xiaozhang Zhu 《Advanced materials (Deerfield Beach, Fla.)》2019,31(51)
Compared with the quick development of polymer solar cells, achieving high‐efficiency small‐molecule solar cells (SMSCs) remains highly challenging, as they are limited by the lack of matched materials and morphology control to a great extent. Herein, two small molecules, BSFTR and Y6, which possess broad as well as matched absorption and energy levels, are applied in SMSCs. Morphology optimization with sequential solvent vapor and thermal annealing makes their blend films show proper crystallinity, balanced and high mobilities, and favorable phase separation, which is conducive for exciton dissociation, charge transport, and extraction. These contribute to a remarkable power conversion efficiency up to 13.69% with an open‐circuit voltage of 0.85 V, a high short‐circuit current of 23.16 mA cm?2 and a fill factor of 69.66%, which is the highest value among binary SMSCs ever reported. This result indicates that a combination of materials with matched photoelectric properties and subtle morphology control is the inevitable route to high‐performance SMSCs. 相似文献
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