RSC Advances
·
2016
·Vol. 6
·期 100
·97783-97790
·
IF 3.289
Ying Sun,Qizan Huang,Xueqin Zhang,Xiaojing Ding,Pei Han,Baoping Lin,Hong Yang,Lingxiang Guo
In recent years, side chain engineering has been proven to play a critical role in the development of high performance conjugated polymers for organic electronics. Here, we report a new strategy to improve charge transport property through side chain functionalization. A series of carbazole–diketopyrrolopyrrole based conjugated polymers P1, P2 and P3 with different side chains have been designed and synthesized. For P2 and P3, a pyrene and carbazole unit were incorporated into the terminal of the alkyl side chain, respectively. Thermal properties, crystallinities, UV-vis absorptions, electrochemical properties as well as charge transport properties of the polymers were investigated in detail. Interestingly, results showed that incorporation of the fused aromatic ring into the side chain terminal not only changed the absorption and electrochemical properties, but also affected the charge transport properties. The pyrene and carbazole group in the side chain terminal significantly promoted aggregation of the polymer chains, which would provide short-range order for improved charge carrier mobility. Compared to the hole mobility (0.019 cm2 V−1 s−1) for polymer P1 with the whole alkyl chains, increased hole mobilities of 0.081 cm2 V−1 s−1 and 0.052 cm2 V−1 s−1 were achieved for polymer P2 and polymer P3, respectively. It is worthy to note that our strategy gives rise to no increment of the crystallinity of the polymer, being beneficial for the practical application of soft electronics since high crystallinity of the material usually leads to poor thin film uniformity and weak mechanical resilience. In this respect, we offer a promising tool to aid rational polymer design for enhanced charge transport property.
研究领域:
高分子化学
·
有机电子学
·
材料科学
·
半导体材料
·
光电功能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS
·
2018
·Vol. 56
·期 11
·833-841
·
IF 2.499
Xinxiu Cao,Liang Chen,Kefeng Zhao,Jiangang Liu,Yanchun Han
Understanding the nucleation process is very important in growing polymer nanowires as it plays a decisive role in determining the crystal structure and size distribution. Polymer chain conformation determines whether the polymer chains could assemble to nuclei or not. Here, chain conformation and the nucleation process were controlled to grow 3,6-bis-(thiophen-2-yl)- N , N ′-bis(2-decyl-1-tetradecyl)-1,4-dioxo-pyrrolo[3,4-c]pyrrole and thieno[3,2-b]thiophene (DT-PDBT-TT) nanowires. We changed the conformation of DT-PDBT-TT in solution and controlled the nucleation process by using a main solvent:cosolvent system. The main solvent was a low boiling point good solvent, and the cosolvent was consisted of two high boiling point solvents with different solubility. In fact, the chain conformation in the pristine solution was changed by choosing different main solvents (with H-bond, π–π or none interaction with the main chain) and temperatures. The absorption spectrum and TEM images showed that trichloro ethylene (TCE) was the best main solvent because it has H-bond interaction with the polymer main chain and DT-PDBT-TT conformation in it approaching unimer coil conformation, which is beneficial to grow nanowires. Mixed o-dichlorobenzene (ODCB) and anisole (AS) with different ratios were used to changing the solubility step by step to control nucleation process. Only when marginal cosolvent (ODCB:AS = 1:1) was added, could it decrease the nuclei number and avoided the aggregates simultaneously. As the main solvent evaporated slowly, the nucleation and growth happened, leading to the nanowires formation. The resulting nanowires were about 63 nm in width and one to two microns in length. The width of the DT-PDBT-TT structures suggests that the polymer chains are oriented along the fibril axis. Our results indicated that there are two requirements for the nanowire formation, (1) the polymer chain conformation should approach unimer coil; (2) the nucleation density should be optimized, not too much and no aggregation happened. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018 , 56 , 833–841
研究领域:
高分子物理
·
材料科学
·
纳米科技
·
凝聚态物理
·
有机电子学
✓ 已验证
DOI
高影响因子
DYES AND PIGMENTS
·
2016
·
IF 4.055
Qing Bao,Hua Li,Yang Li,Jinghui He,Qingfeng Xu,Najun Li,Dongyun Chen,Lihua Wang,Jianmei Lu
In this paper, two acceptor-donor-acceptor (A-D-A) type organic small molecules, 4,4'-(5,5'-(benzo[c] [1,2,5]thiadiazole-4,7-diyl)bis(3-hexylthiophene-5,2-diyl))bis(N-(4-nitrophenyl)-N-phenylaniline) (NTPA 2 TBT) and 4,4'-(5,6-difluorobenzo[c] [1,2,5]thiadiazole-4,7-diyl)bis(N-(4-nitrophenyl)-N-phenylaniline) (NTPA 2 BTF 2 ), were synthesized and fabricated into resistive random access memory devices. Compared with our previously reported molecule NTPA 2 BT, NTPA 2 TBT has 3-hexylthiophene linkages bridging its donor and acceptor, while there are two additional fluorine atoms in the benzothiadiazole moiety for NTPA 2 BTF 2. Both the fabricated memory devices based on these two new molecules perform nonvolatile ternary memory characteristics with lower threshold voltages , higher reproducibility and better stability. The addition of 3-hexylthiophene bridges significantly promotes the planarity of the conjugation backbone and facilitates the molecular stacking, while the substitution hydrogen by fluorine improves the intermolecular interaction , and thus also induces an ordered molecular stacking. The insertion of 3-hexylthiophene bridges or fluorine atoms could be an effective strategy of tailoring organic molecules to improve data storage performance with lower power consumption.
研究领域:
材料科学
·
有机电子学
·
分子器件
·
非易失性存储器
·
高分子化学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2017
·
IF 7.504
Wang Li,Zhiyang Liu,Rongjuan Yang,Qian Guan,Weigang Jiang,Amjad Islam,Tao Lei,Ling Hong,Ruixiang Peng,Ziyi Ge
The development of simple and water-/alcohol-soluble interfacial materials is crucial for the cost-effective fabrication process of polymer solar cells (PSCs). Herein, highly efficient PSCs are reported employing water-/alcohol-soluble and low-cost rhodamines as cathode interfacial layers (CILs). The results reveal that rhodamine-based CILs can reduce the work function of the Al cathode and simultaneously increase the open-circuit voltage, current density, fill factor, and power conversion efficiency (PCE) of PSCs. The solution-processed rhodamine-based PSCs demonstrated a remarkable PCE of 10.39%, which is one of the best efficiencies reported for thieno[3,4-b]thiophene/benzodithiophene:[6,6]-phenyl C71-butyric acid methyl ester-based PSCs so far. The efficiency is also 42.3% higher than that of the vacuum-deposited Ca-based device (PCE of 7.30%) and 21.5% higher than that of the complicated solution-processable polymeric electrolyte poly[(9,9-bis(3-(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)]-based device (PCE of 8.55%). Notably, rhodamines are very economical and have been extensively used as dyes in industries. Our work indicates that rhodamines have shown a strong potential as CILs compared to their counterparts in the large-area fabrication process of PSCs.
研究领域:
材料科学
·
光伏技术
·
有机电子学
·
高分子化学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2015
·Vol. 4
·期 1
·297-302
·
IF 7.443
Xiaohui Liu,Yulei Wu,Xiaodong Li,Wenjun Zhang,Lixiao Zhao,Hai-Qiao Wang,Junfeng Fang
Phenanthroline based organic semiconductors (BCP, Bphen, Mphen, and Phen) are used to hybrid with CdS as cathode interlayers in inverted organic solar cells (OSCs). We observed that selecting the polar solvent and hydrophobic interlayers with a diphenyl group could improve the performance of the organic photovoltaic devices. The modification to CdS can effectively improve its electron mobility, film morphology, interfacial contact, and energy level alignment, which finally leads to a significant enhancement of device performance. Through incorporating the CdS–P hybrids (CdS–BCP, CdS–Bphen, CdS–Mphen, and CdS–Phen) as cathode buffer layers, the device PCE (PTB7 : PC71BM as the active layer) is greatly improved from 3.09% to 8.36, 7.84, 6.69, and 6.57%, respectively, compared with devices fabricated on the pristine CdS interlayer. These results indicate that the common inorganic semiconductor like CdS can be modified using some organic semiconductors to produce general applicable electron transport layers applied in OSCs. Our work puts forward new insights for the development of new interface modification materials and fabrication of high efficiency devices.
研究领域:
材料科学
·
有机电子学
·
光伏技术
·
纳米技术
·
半导体器件
✓ 已验证
DOI
高影响因子
ACS Nano
·
2017
·
IF 13.942
Junqing Zhao,Hang Guo,Yao Kun Pang,Fengben Xi,Zhi Wei Yang,Guoxu Liu,Tong Guo,Guifang Dong,Chi Zhang,Zhong Lin Wang
Flexible electronics has attracted enormous interest in wearable electronics and human–machine interfacing. Here, a flexible organic tribotronic transistor (FOTT) without a top gate electrode has been demonstrated. The FOTT is fabricated on a flexible polyethylene terephthalate film using the p-type pentacene and poly(methyl methacrylate)/Cytop composites as the conductive channel and dielectric layer, respectively. The charge carriers can be modulated by the contact electrification between the dielectric layer and a mobile triboelectric layer. Based on the fabricated FOTT, pressure and magnetic sensors have been developed, respectively, that exhibit great sensitivity, fast response time, and excellent stability. The FOTT in this simple structure shows bright potentials of tribotronics in human–machine interaction, electronic skins, wearable electronics, intelligent sensing, and so on.
研究领域:
柔性电子学
·
传感器技术
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有机电子学
·
可穿戴设备
·
人机交互
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2016
·
IF 4.803
Junsheng Luo,Zhongquan Wan,Chunyang Jia,Yan Wang,Xiaochun Wu
Compared with the development of novel organic dyes, co-sensitization is a much more convenient way to achieve highly efficient dye-sensitized solar cells (DSSCs). Here, two simple donor-(π conjugated spacer)-acceptor dyes, in which hexyloxy-substituted phenyl as an electron donor, cyanoacrylic acid as the electron acceptor and different spacers thiophene ( LD03 ) or furan ( LD04 ) as the π-linkers, were designed and synthesized as co-sensitizers for N719 -based DSSCs . The photophysical, electrochemical, photovoltaic performances and electrochemical impedance spectroscopy of these DSSCs were investigated in detail. When compared to the DSSCs fabricated from individual N719 , the co-sensitized DSSCs ( N719 + LD03 and N719 + LD04 ) showed significantly enhanced power conversion efficiencies (PCEs), short-circuit photocurrent density ( J sc ) and open circuit voltage ( V oc ) simultaneously, which owing to the co-sensitizers could effectively overcome the competitive light absorption by I 3 − in the electrolyte, avoid dye aggregation and reduce the charge recombination. Consequently, the co-sensitized DSSC ( N719 + LD04 ) gave the highest PCE of 8.955% ( J sc = 17.628 mA cm −2 , V oc = 0.758 V and fill factor = 0.670), exhibiting an improvement of 13.412% compared to the device sensitized with N719 alone (PCE = 7.896%) under illumination (AM 1.5G, 100 mW cm −2 ).
研究领域:
材料科学
·
光伏技术
·
有机电子学
·
可再生能源
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2016
·
IF 7.145
Zhong-Min Bao,Rui-Peng Xu,Chi Li,Zhong-Zhi Xie,Xin-Dong Zhao,Yi-Bo Zhang,Yan-Qing Li,Jian-Xin Tang
Charge transport at organic/inorganic hybrid contacts significantly affects the performance of organic optoelectronic devices because the unfavorable energy level offsets at these interfaces can hinder charge injection or extraction due to large barrier heights. Herein, we report a technologically relevant method to functionalize a traditional hole-transport layer of solution-processed nickel oxide (NiOx) with various interlayers. The photoemission spectroscopy measurements reveal the continuous tuning of the NiOx substrate work function ranging from 2.5 to 6.6 eV, enabling the alignment transition of energy levels between the Schottky–Mott limit and Fermi level pinning at the organic/composite NiOx interface. As a result, switching hole and electron transport for the active organic material on the composite NiOx layer is achieved due to the controlled carrier injection/extraction barriers. The experimental findings indicate that tuning the work function of metal oxides with optimum energy level offsets can facilitate the charge transport at organic/electrode contacts.
研究领域:
材料科学
·
有机电子学
·
表面科学
·
能级工程
·
光电子器件
✓ 已验证
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 103
·101645-101651
·
IF 3.289
Zelin Li,Dalei Yang,Xiaoli Zhao,Zidong Li,Tong Zhang,Fan Wu,Xiaoniu Yang
A water-soluble small-molecule perylene diimide derivative functionalized with a propylenetrimethylammonium end group, namely N,N-bis(propylenetrimethyl ammonium)-3,4,9,10-perylenediimide (PDI-N3I), was synthesized and successfully applied to conventional polymer solar cells as the cathode interlayer firstly. The small-molecule PDI-N3I showed excellent solubility in water and a desirable LUMO energy level of −4.09 eV which matches well with that of PC71BM. With incorporation of the PDI-N3I cathode interlayer, a PDI-N3I/Al device exhibited a higher PCE of 7.00% than that (6.54%) of a LiF/Al device resulting from the improved short current density from 10.41 mA cm−2 to 11.44 mA cm−2, which benefitted from the more efficient electron extracting ability of PDI-N3I compared with LiF proved by photoluminescence quenching experiment. The high vertical conductivity of PDI-N3I endows it with the outstanding property of thickness insensitivity, which is compatible with roll-to-roll production. Additionally, device performance was further improved by the use of a PDI-N3I/LiF bilayered cathode interlayer and the highest PCE of 7.18% was achieved. This work provides a novel solution-processed cathode interlayer material which could effectively improve the efficiency of polymer solar cells.
研究领域:
材料科学
·
光伏技术
·
有机电子学
·
高分子化学
✓ 已验证
DOI
高影响因子
Advanced Intelligent Systems
·
2019
·Vol. 1
·期 3
·1900022
·
IF 0
Yang Feng,Xu Gao,Ya-Nan Zhong,Jia-Ling Wu,Jian-Long Xu,Sui-Dong Wang
Emerging organic synaptic devices are promising in exploring soft and biocompatible neuromorphic computing systems. By means of a simple and low-cost solution process, the polymer thin-film memristors are designed and characterized. The polymer memristors have a bilayer structure composed of an ion-rich semiconducting layer and an ion-collecting conducting layer, where the ion redistribution depending on device operation history has an impact on carrier concentration and results in the memristive characteristics. A visible electrochromic feature is observed during the electrical measurements, supporting the proposed Li + ion drift/diffusion mechanism. The polymer memristors show the continuous and reversible conductivity tuning with a temporary memory effect, which enables the successful emulation of the frequency-dependent synaptic plasticity. The polymer thin-film memristors may offer a strategy for developing building blocks of organic neuromorphic circuits.
研究领域:
生物电子学
·
神经形态工程
·
有机电子学
·
分子器件
·
生物医学工程
✓ 已验证
DOI
Physica Status Solidi-Rapid Research Letters
·
2020
·Vol. 14
·期 4
·1900723
·
IF 2.291
Yadan Deng,Jingzan Jiang,Jun Sun,Yufeng Hu,Qiuhong Cui,Zhenbo Deng,Zhidong Lou,Yanbing Hou,Feng Teng
Fabrication of nanowires in polymer films can dramatically enhance the mobility of thin-film transistors (TFTs). Unlike the popular method of forming nanowires after spin-coating films, here a water-bath method to fabricate the micrometer-long nanowires in the poly(3-hexylthiophene) (P3HT) solution is introduced, which is suitable for large-area printing electronic application. The resulting transistor exhibits significantly enhanced mobility and excellent device stability. However, the threshold voltage of the device is increased, compared with the amorphous film device. The underlying mechanism of the mesoscale crystalline induced threshold voltage increase has been rarely studied. The temperature-dependent characteristics imply that the activation energy of the device with nanowires is higher than that of the amorphous one, indicating nanowires can introduce deep traps. This suggests that the charge transport is mainly limited by the deep traps at the junctions between the nanowires considering the trap density inside the nanowires is significantly low. The deep traps introduced by the junctions can increase the threshold voltage as the device needs higher voltage to fill these traps in the channel before the device is turned on. This explains why the devices with nanowires have an increased threshold voltage while their mobilities are dramatically enhanced.
研究领域:
材料科学
·
凝聚态物理
·
有机电子学
·
薄膜晶体管
·
半导体器件物理
✓ 已验证
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2020
·Vol. 22
·期 23
·13214-13222
·
IF 3.43
Yongfang Yuan,Xiaowen Zhang,Dongliang Li,Xiuyun Zhang,Lihui Wang,Zongliu Lu,Liming Liu,Feng Chi
Hole injection governs the efficiency of ultraviolet organic light-emitting diodes (UV OLEDs) due to the deep highest occupied molecular orbital level of the emissive molecule. Tungsten oxides (WOx), transition metal oxides with high work functions and good stability, cast light on solving this problem. By a low-cost, scalable and high-throughput manufacturing process, herein the facile synthesis of a WOx solution and its doping in poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS + WOx) is systematically investigated for assembling efficient UV OLEDs. X-ray diffraction, atomic force microscopy, scanning electron microscopy and X-ray photoelectron spectroscopy measurements confirm that WOx and PEDOT:PSS + WOx have good film morphology and exceptional electronic properties, such as the oxygen deficiency dominated non-stoichiometry of WOx. With PEDOT:PSS + WOx tailoring hole injection and 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole as the emitter, the UV OLEDs show outstanding electro-optic performance, with a radiance of 3.98 mW cm−2, external quantum efficiency of 2.30%, electroluminescence peak at 400 nm and full width at half maximum of 47 nm, which is superior to the performance of the corresponding reference materials. The mechanism of charge transfer from the PEDOT polycation to WOx, enhancing conductivity, is responsible for the robust hole injection/transport and is further elucidated by ultraviolet photoelectron spectroscopy and impedance spectroscopy, contributing to the optimization of the carrier balance and recombination zone. Our results illustrate an alternative approach for boosting UV OLED performance and advancing organic electronics.
研究领域:
材料科学
·
有机电子学
·
薄膜器件
·
光电功能材料
·
半导体器件物理
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）