共查询到20条相似文献,搜索用时 0 毫秒
1.
Junwoo Lee Jae Won Kim Sang Ah Park Sung Yun Son Kyoungwon Choi Woojin Lee Minjun Kim Jin Young Kim Taiho Park 《Liver Transplantation》2019,9(34)
This work deals with the investigation of burn‐in loss in ternary blended organic photovoltaics (OPVs) prepared from a UV‐crosslinkable semiconducting polymer (P2FBTT‐Br) and a nonfullerene acceptor (IEICO‐4F) via a green solvent process. The synthesized P2FBTT‐Br can be crosslinked by UV irradiation for 150 s and dissolved in 2‐methylanisole due to its asymmetric structure. In OPV performance and burn‐in loss tests performed at 75 °C or AM 1.5G Sun illumination for 90 h, UV‐crosslinked devices with PC71BM show 9.2% power conversion efficiency (PCE) and better stability against burn‐in loss than pristine devices. The frozen morphology resulting from the crosslinking prevents lateral crystallization and aggregation related to morphological degradation. When IEICO‐4F is introduced in place of a fullerene‐based acceptor, the burn‐in loss due to thermal aging and light soaking is dramatically suppressed because of the frozen morphology and high miscibility of the nonfullerene acceptor (18.7% → 90.8% after 90 h at 75 °C and 37.9% → 77.5% after 90 h at AM 1.5G). The resulting crosslinked device shows 9.4% PCE (9.8% in chlorobenzene), which is the highest value reported to date for crosslinked active materials, in the first green processing approach. 相似文献
2.
Xiaoling Ma Jian Wang Jinhua Gao Zhenghao Hu Chunyu Xu Xiaoli Zhang Fujun Zhang 《Liver Transplantation》2020,10(31)
A power conversion efficiency (PCE) of 16.2% is achieved in PM6:BTP‐4F‐12 based organic photovoltaics (OPVs). On the basis of efficient binary OPVs, a series of ternary OPVs are constructed by incorporating MeIC as the third component. The open circuit voltages (VOCs) of ternary OPVs can be gradually increased along with the incorporation of MeIC, suggesting the formation of an alloy state between BTP‐4F‐12 and MeIC with good compatibility. The energy loss (Eloss) of ternary OPVs can be decreased compared with that of two binary OPVs, contributing to the VOC improvement of ternary OPVs. The short circuit current density (JSC) and fill factor (FF) of ternary OPVs can also be simultaneously enhanced with MeIC content up to 10 wt% in acceptors, leading to 17.4% PCE of the optimized ternary OPVs. The JSC and FF improvement of ternary OPVs is thought to result from the optimized ternary active layers with more efficient photon harvesting, exciton dissociation and charge transport. The 17.4% PCE and 79.2% FF is among the top values of ternary OPVs. This work indicates that a ternary strategy is an emerging method to simultaneously minimize Eloss and optimize photon harvesting as well as improve the morphology of active layers for realizing performance improvement for OPVs. 相似文献
3.
Organic Photovoltaics: Charge Photogeneration in Organic Photovoltaics: Role of Hot versus Cold Charge‐Transfer Excitons (Adv. Energy Mater. 1/2016) 下载免费PDF全文
Bhoj R. Gautam Robert Younts Wentao Li Liang Yan Evgeny Danilov Erik Klump Iordania Constantinou Franky So Wei You Harald Ade Kenan Gundogdu 《Liver Transplantation》2016,6(1)
4.
5.
6.
NDI‐Based Small Molecule as Promising Nonfullerene Acceptor for Solution‐Processed Organic Photovoltaics 下载免费PDF全文
Yao Liu Lei Zhang Hyunbok Lee Hsin‐Wei Wang Annikki Santala Feng Liu Ying Diao Alejandro L. Briseno Thomas P. Russell 《Liver Transplantation》2015,5(12)
A novel naphthalene diimide (NDI)‐based small molecule (BiNDI) is designed and synthesized by linking two NDI monomers via a vinyl donor moiety. The electronic structure of BiNDI is carefully investigated by ultraviolet photoelectron spectroscopy (UPS). Density functional theory (DFT) sheds further light on the molecular configuration and energy level distribution. Thin film transistors (TFT) based on BiNDI show a highest electron mobility of 0.365 cm2 V?1 s?1 in ambient atmosphere. Organic photovoltaics (OPVs) by using BiNDI as the acceptor show a highest power conversion efficency (PCE) of 2.41%, which is the best result for NDI‐based small molecular acceptors. Transmission electron microscopy (TEM), atomic force microscopy (AFM), grazing incidence wide‐angle X‐ray diffraction (GIXD), and X‐ray photoelectron spectroscopy (XPS) characterization to understand the morphology and structure order of the bulk heterojunction film are performed. It is found that small amount of 1,8‐diiodooctane (DIO) (i.e., 0.5%) in the blended film facilitates the crystallization of BiNDI into fibrillar crystals, which is beneficial for the improvement of device performance. 相似文献
7.
Organic Photovoltaics: Low Band Gap Polymer Solar Cells With Minimal Voltage Losses (Adv. Energy Mater. 18/2016) 下载免费PDF全文
Chuanfei Wang Xiaofeng Xu Wei Zhang Jonas Bergqvist Yuxin Xia Xiangyi Meng Kim Bini Wei Ma Arkady Yartsev Koen Vandewal Mats R. Andersson Olle Inganäs Mats Fahlman Ergang Wang 《Liver Transplantation》2016,6(18)
8.
Solar Cells: High‐Performance and Stable All‐Polymer Solar Cells Using Donor and Acceptor Polymers with Complementary Absorption (Adv. Energy Mater. 14/2017) 下载免费PDF全文
Zhaojun Li Wei Zhang Xiaofeng Xu Zewdneh Genene Dario Di Carlo Rasi Wendimagegn Mammo Arkady Yartsev M. R. Andersson René A. J. Janssen Ergang Wang 《Liver Transplantation》2017,7(14)
9.
10.
James Kirkpatrick Christian B. Nielsen Weimin Zhang Hugo Bronstein R. Shahid Ashraf Martin Heeney Iain McCulloch 《Liver Transplantation》2012,2(2):260-265
The synthesis and optimization of new photovoltaic donor polymers is a time‐consuming process. Computer‐based molecular simulations can narrow the scope of materials choice to the most promising ones, by identifying materials with desirable energy levels and absorption energies. In this paper, such a retrospective analysis is presented of a series of fused aromatic push–pull copolymers. It is demonstrated that molecular calculations do indeed provide good estimates of the absorption energies measured by UV–vis spectroscopy and of the ionization potentials measured by photoelectron spectroscopy in air. Comparing measured photovoltaic performance of the polymer series to the trend in efficiencies predicted by computation confirms the validity of this approach. 相似文献
11.
Microstructural and Electronic Origins of Open‐Circuit Voltage Tuning in Organic Solar Cells Based on Ternary Blends 下载免费PDF全文
Organic ternary heterojunction photovoltaic blends are sometimes observed to undergo a gradual evolution in open‐circuit voltage (Voc) with increasing amounts of a second donor or an acceptor. The Voc is strongly correlated with the energy of the charge transfer state in the blend, but this value depends on both local and mesoscopic orders. In this work, the behavior of Voc in the presence of a wide range of interfacial electronic states is investigated. The key charge transfer state interfaces responsible for Voc in several model systems with varying morphology are identified. Systems consisting of one donor with two fullerene molecules and of one acceptor with a donor polymer of varying regio‐regularity are used. The effects from the changing energetic disorder in the material and from the variation due to a law of simple mixtures are quantified. It has been found that populating the higher‐energy charge transfer states is not responsible for the observed change in Voc upon the addition of a third component. Aggregating polymers and miscible fullerenes are compared, and it has been concluded that in both cases charge delocalization, aggregation, and local polarization effects shift the lowest‐energy charge transfer state distribution. 相似文献
12.
Masahiko Saito Tomohiro Fukuhara Satoshi Kamimura Hiroyuki Ichikawa Hiroyuki Yoshida Tomoyuki Koganezawa Yutaka Ie Yasunari Tamai Hyung Do Kim Hideo Ohkita Itaru Osaka 《Liver Transplantation》2020,10(7)
Controlling the energetics and backbone order of semiconducting polymers is essential for the performance improvement of polymer‐based solar cells. The use of fluorine as the substituent for the backbone is known to effectively deepen the molecular orbital energy levels and coplanarize the backbone by noncovalent interactions with sulfur of the thiophene ring. In this work, novel semiconducting polymers are designed and synthesized based on difluoronaphthobisthiadiazole (FNTz) as a new family of naphthobisthiadiazole (NTz)–quaterthiophene copolymer systems, which are one of the highest performing polymers in solar cells. The effect of the fluorination position on the energetics and backbone order is systematically studied. It is found that the dependence of the solar cell fill factor on the active layer thickness is very sensitive to the fluorination position. It is thus further investigated and discussed how the structural features of the polymers influence the photovoltaic parameters as well as the diode characteristics and bimolecular recombination. Further, the polymer with fluorine on both the naphthobisthiadiazole and quaterthiophene moieties exhibits a quite high power conversion efficiency of 10.8% in solar cells in combination with a fullerene. It is believed that the results would offer new insights into the development of semiconducting polymers. 相似文献
13.
14.
15.
16.
17.
Polymer Solar Cells: High‐Efficiency Inverted Polymer Photovoltaics via Spectrally Tuned Absorption Enhancement (Adv. Energy Mater. 14/2014) 下载免费PDF全文
Stephen Loser Brent Valle Kyle A. Luck Charles K. Song Gabriel Ogien Mark C. Hersam Kenneth D. Singer Tobin J. Marks 《Liver Transplantation》2014,4(14)
18.
19.
Photovoltaics: Toward a Low‐Cost Artificial Leaf: Driving Carbon‐Based and Bifunctional Catalyst Electrodes with Solution‐Processed Perovskite Photovoltaics (Adv. Energy Mater. 20/2016) 下载免费PDF全文
Tiva Sharifi Christian Larsen Jia Wang Wai Ling Kwong Eduardo Gracia‐Espino Guillaume Mercier Johannes Messinger Thomas Wågberg Ludvig Edman 《Liver Transplantation》2016,6(20)