共查询到20条相似文献,搜索用时 15 毫秒
1.
Shiau‐Shin Cheng Peng‐Yi Huang Mohan Ramesh Hsiu‐Chieh Chang Li‐Ming Chen Chia‐Ming Yeh Chun‐Lin Fung Meng‐Chyi Wu Chung‐Chi Liu Choongik Kim Hong‐Cheu Lin Ming‐Chou Chen Chih‐Wei Chu 《Advanced functional materials》2014,24(14):2057-2063
Solution‐processed small‐molecule bulk heterojunction (BHJ) ambipolar organic thin‐film transistors are fabricated based on a combination of [2‐phenylbenzo[d,d']thieno[3,2‐b;4,5‐b']dithiophene (P‐BTDT) : 2‐(4‐n‐octylphenyl)benzo[d,d ']thieno[3,2‐b;4,5‐b']dithiophene (OP‐BTDT)] and C60. Treating high electrical performance vacuum‐deposited P‐BTDT organic semiconductors with a newly developed solution‐processed organic semiconductor material, OP‐BTDT, in an optimized ratio yields a solution‐processed p‐channel organic semiconductor blend with carrier mobility as high as 0.65 cm2 V?1 s?1. An optimized blending of P‐BTDT:OP‐BTDT with the n‐channel semiconductor, C60, results in a BHJ ambipolar transistor with balanced carrier mobilities for holes and electrons of 0.03 and 0.02 cm2 V?1 s?1, respectively. Furthermore, a complementary‐like inverter composed of two ambipolar thin‐film transistors is demonstrated, which achieves a gain of 115. 相似文献
2.
Ming L. Tang Anna D. Reichardt Toshihiro Okamoto Nobuyuki Miyaki Zhenan Bao 《Advanced functional materials》2008,18(10):1579-1585
A series of compounds from the tetraceno[2,3‐b]thiophene and the anthra[2,3‐b]thiophene family of semiconducting molecules has been made. Specifically, synthetic routes to functionalize the parent molecules with bromo and then hexyl groups are shown. The bromo‐ and hexyl‐functionalized tetraceno[2,3‐b]thiophene and anthra[2,3‐b]thiophene were characterized in the top‐contact thin‐film transistor (TFT) geometry. They give high mobilities, ranging from 0.12 cm2 V?1 s?1 for α‐n‐hexylanthra[2,3‐ b]thiophene to as high as 0.85 cm2 V?1 s?1 for α‐bromotetraceno[2,3‐b]thiophene. Notably, grain size increases, going from the shorter anthra[2,3‐b]thiophene core to the longer tetraceno[2,3‐b]thiophene core, with a corresponding increase in mobility. The transition from undesirable 3D to desirable 2D thin‐film growth is explained by the increase in length of the molecule, in this case by one benzene ring, which results in an increase in intralayer interactions relative to interlayer interactions. 相似文献
3.
Y.M. Sun Y.Q. Ma Y.Q. Liu Y.Y. Lin Z.Y. Wang Y. Wang C.A. Di K. Xiao X.M. Chen W.F. Qiu B. Zhang G. Yu W.P. Hu D.B. Zhu 《Advanced functional materials》2006,16(3)
A series of new organic semiconductors for organic thin‐film transistors using dithieno[3,2‐b:2′,3′‐d]thiophene as the core have been synthesized. In work reported by Liu, Zhu, and co‐workers on p. 426, the phenyl‐substituted compound exhibited a high mobility of 0.42 cm2 V–1 s–1 and an on/off ratio of 5 × 106. Weekly shelf‐life tests of the transistors based on the bis(diphenyl)‐substituted thiophene under ambient conditions showed that the mobility was almost unchanged after more than two months, demonstrating potential for applications in future organic electronics. A series of new organic semiconductors for organic thin‐film transistors (OTFTs) using dithieno[3,2‐b:2′,3′‐d]thiophene as the core are synthesized. Their electronic and optical properties are investigated using scanning electron microscopy (SEM), X‐ray diffraction (XRD), UV‐vis and photoluminescence spectroscopies, thermal gravimetric analysis (TGA), and differential scanning calorimetry (DSC). The compounds exhibit an excellent field‐effect performance with a high mobility of 0.42 cm2 V–1 s–1 and an on/off ratio of 5 × 106. XRD patterns reveal these films, grown by vacuum deposition, to be highly crystalline, and SEM reveals well‐interconnected, microcrystalline domains in these films at room temperature. TGA and DSC demonstrate that the phenyl‐substituted compounds possess excellent thermal stability. Furthermore, weekly shelf‐life tests (under ambient conditions) of the OTFTs based on the phenyl‐substituted compounds show that the mobility for the bis(diphenyl)‐substituted thiophene was almost unchanged for more than two months, indicating a high environmental stability. 相似文献
4.
Donor–Acceptor Poly(3‐hexylthiophene)‐block‐Pendent Poly(isoindigo) with Dual Roles of Charge Transporting and Storage Layer for High‐Performance Transistor‐Type Memory Applications 下载免费PDF全文
Jau‐Tzeng Wang Shoichi Takashima Hung‐Chin Wu Yu‐Cheng Chiu Yougen Chen Takuya Isono Toyoji Kakuchi Toshifumi Satoh Wen‐Chang Chen 《Advanced functional materials》2016,26(16):2695-2705
Field‐effect transistor memories usually require one additional charge storage layer between the gate contact and organic semiconductor channel. To avoid such complication, new donor–acceptor rod–coil diblock copolymers (P3HT44‐b‐Pison) of poly(3‐hexylthiophene) (P3HT)‐block‐poly(pendent isoindigo) (Piso) are designed, which exhibit high performance transistor memory characteristics without additional charge storage layer. The P3HT and Piso blocks are acted as the charge transporting and storage elements, respectively. The prepared P3HT44‐b‐Pison can be self‐assembled into fibrillar‐like nanostructures after the thermal annealing process, confirmed by atomic force microscopy and grazing‐incidence X‐ray diffraction. The lowest‐unoccupied molecular orbital levels of the studied polymers are significantly lowered as the block length of Piso increases, leading to a stronger electron affinity as well as charge storage capability. The field‐effect transistors (FETs) fabricated from P3HT44‐b‐Pison possess p‐type mobilities up to 4.56 × 10?2 cm2 V?1 s?1, similar to that of the regioregular P3HT. More interestingly, the FET memory devices fabricated from P3HT44‐b‐Pison exhibit a memory window ranging from 26 to 79 V by manipulating the block length of Piso, and showed stable long‐term data endurance. The results suggest that the FET characteristics and data storage capability can be effectively tuned simultaneously through donor/acceptor ratio and thin film morphology in the block copolymer system. 相似文献
5.
Alkoxy‐Functionalized Thienyl‐Vinylene Polymers for Field‐Effect Transistors and All‐Polymer Solar Cells 下载免费PDF全文
Hui Huang Nanjia Zhou Rocio Ponce Ortiz Zhihua Chen Stephen Loser Shiming Zhang Xugang Guo Juan Casado J. Teodomiro López Navarrete Xinge Yu Antonio Facchetti Tobin J. Marks 《Advanced functional materials》2014,24(19):2782-2793
π‐conjugated polymers based on the electron‐neutral alkoxy‐functionalized thienyl‐vinylene (TVTOEt) building‐block co‐polymerized, with either BDT (benzodithiophene) or T2 (dithiophene) donor blocks, or NDI (naphthalenediimide) as an acceptor block, are synthesized and characterized. The effect of BDT and NDI substituents (alkyl vs alkoxy or linear vs branched) on the polymer performance in organic thin film transistors (OTFTs) and all‐polymer organic photovoltaic (OPV) cells is reported. Co‐monomer selection and backbone functionalization substantially modifies the polymer MO energies, thin film morphology, and charge transport properties, as indicated by electrochemistry, optical spectroscopy, X‐ray diffraction, AFM, DFT calculations, and TFT response. When polymer P7 is used as an OPV acceptor with PTB7 as a donor, the corresponding blend yields TFTs with ambipolar mobilities of μe = 5.1 × 10?3 cm2 V–1 s–1 and μh = 3.9 × 10?3 cm2 V–1 s–1 in ambient, among the highest mobilities reported to date for all‐polymer bulk heterojunction TFTs, and all‐polymer solar cells with a power conversion efficiency (PCE) of 1.70%, the highest reported PCE to date for an NDI‐polymer acceptor system. The stable transport characteristics in ambient and promising solar cell performance make NDI‐type materials promising acceptors for all‐polymer solar cell applications. 相似文献
6.
Y.M. Sun Y.Q. Ma Y.Q. Liu Y.Y. Lin Z.Y. Wang Y. Wang C.A. Di K. Xiao X.M. Chen W.F. Qiu B. Zhang G. Yu W.P. Hu D.B. Zhu 《Advanced functional materials》2006,16(3):426-432
A series of new organic semiconductors for organic thin‐film transistors (OTFTs) using dithieno[3,2‐b:2′,3′‐d]thiophene as the core are synthesized. Their electronic and optical properties are investigated using scanning electron microscopy (SEM), X‐ray diffraction (XRD), UV‐vis and photoluminescence spectroscopies, thermal gravimetric analysis (TGA), and differential scanning calorimetry (DSC). The compounds exhibit an excellent field‐effect performance with a high mobility of 0.42 cm2 V–1 s–1 and an on/off ratio of 5 × 106. XRD patterns reveal these films, grown by vacuum deposition, to be highly crystalline, and SEM reveals well‐interconnected, microcrystalline domains in these films at room temperature. TGA and DSC demonstrate that the phenyl‐substituted compounds possess excellent thermal stability. Furthermore, weekly shelf‐life tests (under ambient conditions) of the OTFTs based on the phenyl‐substituted compounds show that the mobility for the bis(diphenyl)‐substituted thiophene was almost unchanged for more than two months, indicating a high environmental stability. 相似文献
7.
A solution‐processable electrochromic (EC) polymer, poly(4,4‐dioctyl‐cyclopenta[2,1‐b:3,4‐b′]‐dithiophene) (PDOCPDT) is prepared by means of chemical oxidative polymerization of the corresponding monomer. The UV‐vis spectrum of the spin‐coated PDOCPDT film displays an absorption maximum of 580 nm. Although the polymer is deep blue in its neutral state, it turns to transparent bluish after being oxidized. PDOCPDT film (thickness 120 nm) exhibits high coloration efficiency (CE)—as high as 932 C cm–2 at 580 nm, low response time (0.75 s), high optical density (0.75 at 580 nm), and high‐level stability for long term switch (it switches repetitively 1000 times with less than 8 % contrast loss). The electrochemical stability and redox potentials of PDOCPDT films are independent of film thickness (50–180 nm) and active area (up to 2 cm × 2 cm). Nevertheless, optical contrast increases as the film thickness increases, although the CE and response time changes irregularly with the film thickness. The good EC properties combined with the easy film fabrication process make PDOCPDT a notable candidate for application in EC devices. (ECDs) A simple transmissive‐type ECD with good CE using PDOCPDT film as an active layer is also demonstrated. 相似文献
8.
N. Drolet J.‐F. Morin N. Leclerc S. Wakim Y. Tao M. Leclerc 《Advanced functional materials》2005,15(10):1671-1682
We have fabricated organic field‐effect transistors based on thin films of 2,7‐carbazole oligomeric semiconductors 1,4‐bis(vinylene‐(N‐hexyl‐2‐carbazole))phenylene (CPC), 1,4‐bis(vinylene‐(N′‐methyl‐7′‐hexyl‐2′‐carbazole))benzene (RCPCR), N‐hexyl‐2,7‐bis(vinylene‐(N‐hexyl‐2‐carbazole))carbazole (CCC), and N‐methyl‐2,7‐bis(vinylene‐(7‐hexyl‐N‐methyl‐2‐carbazole))carbazole (RCCCR). The organic semiconductors are deposited by thermal evaporation on bare and chemically modified silicon dioxide surfaces (SiO2/Si) held at different temperatures varying from 25 to 200 °C during deposition. The resulting thin films have been characterized using UV‐vis and Fourier‐transform infrared spectroscopies, scanning electron microscopy, and X‐ray diffraction, and the observed top‐contact transistor performances have been correlated with thin‐film properties. We found that these new π‐conjugated oligomers can form highly ordered structures and reach high hole mobilities. Devices using CPC as the active semiconductor have exhibited mobilities as high as 0.3 cm2 V–1 s–1 with on/off current ratios of up to 107. These features make CPC and 2,7‐carbazolenevinylene‐based oligomers attractive candidates for device applications. 相似文献
9.
Junying Liu Dahlia Haynes Courtney Balliet Rui Zhang Tomasz Kowalewski Richard D. McCullough 《Advanced functional materials》2012,22(5):1024-1032
Conjugated rod‐coil block copolymers provide an interesting route towards enhancing the properties of the conjugated block due to self‐assembly and the interplay of rod‐rod and rod‐coil interactions. Here, we demonstrate the ability of an attached semi‐fluorinated block to significantly improve upon the charge carrier properties of regioregular poly(3‐hexyl thiophene) (rr‐P3HT) materials on bare SiO2. The thin film hole mobilities on bare SiO2 dielectric surfaces of poly (3‐hexyl thiophene)‐block‐polyfluoromethacrylates (P3HT‐b‐PFMAs) can approach up to 0.12 cm2 V?1 s?1 with only 33 wt% of the P3HT block incorporated in the copolymer, as compared to rr‐P3HT alone which typically has mobilities averaging 0.03 cm2 V?1 s?1. To our knowledge, this is the highest mobility reported in literature for block copolymers containing a P3HT. More importantly, these high hole mobilities are achieved without multistep OTS treatments, argon protection, or post‐annealing conditions. Grazing incidence wide‐angle x‐ray scattering (GIWAX) data revealed that in the P3HT‐b‐PFMA copolymers, the P3HT rod block self‐assembles into highly ordered lamellar structures, similar to that of the rr‐P3HT homopolymer. Grazing incidence small‐angle x‐ray scattering (GISAXS) data revealed that lamellar structures are only observed in perpendicular direction with short PFMA blocks, while lamellae in both perpendicular and parallel directions are observed in polymers with longer PFMA blocks. AFM, GIWAXS, and contact angle measurements also indicate that PFMA block assembles at the polymer thin film surface and forms an encapsulation layer. The high charge carrier mobilities and the hydrophobic surface of the block copolymer films clearly demonstrates the influence of the coil block segment on device performance by balancing the crystallization and microphase separation in the bulk morphological structure. 相似文献
10.
S. Mohapatra B.T. Holmes C.R. Newman C.F. Prendergast C.D. Frisbie M.D. Ward 《Advanced functional materials》2004,14(6):605-609
Thin films based on the tolyl‐substituted oligothiophenes 5,5′′‐bis(4‐methylphenyl)‐2,2′:5′,2′′‐terthiophene ( 1 ), 5,5′′′‐bis(4‐methylphenyl)‐2,2′:5′,2′′:5′′,2′′′‐quaterthiophene ( 2 ) and 5,5′′′′‐bis(4‐methylphenyl)‐2,2′:5′,2′′:5′′,2′′′:5′′′,2′′′′‐quinqethiophene ( 3 ) exhibit hole‐transport behavior in a thin‐film transistor (TFT) configuration, with reasonable mobilities and high current on/off (Ion/Ioff) ratios. Powder X‐ray diffraction (PXRD) reveals that these films, grown by vacuum deposition onto the thermally grown silicon oxide surface of a TFT, are highly crystalline, a characteristic that can be attributed to the general tendency of phenyl groups to promote crystallinity. Atomic force microscopy (AFM) reveals that the films grow layer by layer to form large domains, with some basal domain areas approaching 1000 μm2. The PXRD and AFM data are consistent with an “end‐on” orientation of the molecules on the oxide substrate. Variable‐temperature current–voltage (I–V) measurements identified the activation regime for hole transport and revealed shallow level traps in thin films of 1 and 2 , and both shallow and deep level traps in thin films of 3 . The activation energies for thin films of 1 , 2 , and 3 were similar, with values of Ea = 121, 100, and 109 meV, respectively. The corresponding trap densities were Ntrap/Nv = 0.012, 0.023, and 0.094, where Ntrap is the number of trap states and Nv is the number of conduction states. The hole mobilities for the three compounds were similar (μ ? 0.03 cm2 V–1 s–1), and the Ion/Ioff ratios were comparable with the highest values reported for organic TFTs, with films of 2 approaching Ion/Ioff = 109 at room temperature. 相似文献
11.
High‐Mobility Naphthalene Diimide and Selenophene‐Vinylene‐Selenophene‐Based Conjugated Polymer: n‐Channel Organic Field‐Effect Transistors and Structure–Property Relationship 下载免费PDF全文
Min Jae Sung Alessandro Luzio Won‐Tae Park Ran Kim Eliot Gann Francesco Maddalena Giuseppina Pace Yong Xu Dario Natali Carlo de Falco Long Dang Christopher R. McNeill Mario Caironi Yong‐Young Noh Yun‐Hi Kim 《Advanced functional materials》2016,26(27):4984-4997
Interdependence of chemical structure, thin‐film morphology, and transport properties is a key, yet often elusive aspect characterizing the design and development of high‐mobility, solution‐processed polymers for large‐area and flexible electronics applications. There is a specific need to achieve >1 cm2 V?1 s?1 field‐effect mobilities (μ) at low processing temperatures in combination with environmental stability, especially in the case of electron‐transporting polymers, which are still lagging behind hole transporting materials. Here, the synthesis of a naphthalene‐diimide based donor–acceptor copolymer characterized by a selenophene vinylene selenophene donor moiety is reported. Optimized field‐effect transistors show maximum μ of 2.4 cm2 V?1 s?1 and promising ambient stability. A very marked film structural evolution is revealed with increasing annealing temperature, with evidence of a remarkable 3D crystallinity above 180 °C. Conversely, transport properties are found to be substantially optimized at 150 °C, with limited gain at higher temperature. This discrepancy is rationalized by the presence of a surface‐segregated prevalently edge‐on packed polymer phase, dominating the device accumulated channel. This study therefore serves the purpose of presenting a promising, high‐electron‐mobility copolymer that is processable at relatively low temperatures, and of clearly highlighting the necessity of specifically investigating channel morphology in assessing the structure–property nexus in semiconducting polymer thin films. 相似文献
12.
Donor and Acceptor Unit Sequences Influence Material Performance in Benzo[1,2‐b:4,5‐b′]dithiophene–6,7‐Difluoroquinoxaline Small Molecule Donors for BHJ Solar Cells 下载免费PDF全文
Kai Wang Ru‐Ze Liang Jannic Wolf Qasim Saleem Maxime Babics Philipp Wucher Maged Abdelsamie Aram Amassian Michael Ryan Hansen Pierre M. Beaujuge 《Advanced functional materials》2016,26(39):7103-7114
Well‐defined small molecule (SM) donors can be used as alternatives to π‐conjugated polymers in bulk‐heterojunction (BHJ) solar cells with fullerene acceptors (e.g., PC61/71BM). Taking advantage of their synthetic tunability, combinations of various donor and acceptor motifs can lead to a wide range of optical, electronic, and self‐assembling properties that, in turn, may impact material performance in BHJ solar cells. In this report, it is shown that changing the sequence of donor and acceptor units along the π‐extended backbone of benzo[1,2‐b:4,5‐b′]dithiophene–6,7‐difluoroquinoxaline SM donors critically impacts (i) molecular packing, (ii) propensity to order and preferential aggregate orientations in thin‐films, and (iii) charge transport in BHJ solar cells. In these systems ( SM1‐3 ), it is found that 6,7‐difluoroquinoxaline ([2F]Q) motifs directly appended to the central benzo[1,2‐b:4,5‐b′]dithiophene (BDT) unit yield a lower‐bandgap analogue ( SM1 ) with favorable molecular packing and aggregation patterns in thin films, and optimized BHJ solar cell efficiencies of ≈6.6%. 1H‐1H DQ‐SQ NMR analyses indicate that SM1 and its counterpart with [2F]Q motifs substituted as end‐group SM3 possess distinct self‐assembly patterns, correlating with the significant charge transport and BHJ device efficiency differences observed for the two analogous SM donors (avg. 6.3% vs 2.0%, respectively). 相似文献
13.
Effect of Spacer Length of Siloxane‐Terminated Side Chains on Charge Transport in Isoindigo‐Based Polymer Semiconductor Thin Films 下载免费PDF全文
Jianguo Mei Hung‐Chin Wu Ying Diao Anthony Appleton Hong Wang Yan Zhou Wen‐Ya Lee Tadanori Kurosawa Wen‐Chang Chen Zhenan Bao 《Advanced functional materials》2015,25(23):3455-3462
A series of isoindigo‐based conjugated polymers (PII2F‐CmSi, m = 3–11) with alkyl siloxane‐terminated side chains are prepared, in which the branching point is systematically “moved away” from the conjugated backbone by one carbon atom. To investigate the structure–property relationship, the polymer thin film is subsequently tested in top‐contact field‐effect transistors, and further characterized by both grazing incidence X‐ray diffraction and atomic force microscopy. Hole mobilities over 1 cm2 V?1 s?1 is exhibited for all soluble PII2F‐CmSi (m = 5–11) polymers, which is 10 times higher than the reference polymer with same polymer backbone. PII2F‐C9Si shows the highest mobility of 4.8 cm2 V?1 s?1, even though PII2F‐C11Si exhibits the smallest π–π stacking distance at 3.379 Å. In specific, when the branching point is at, or beyond, the third carbon atoms, the contribution to charge transport arising from π–π stacking distance shortening becomes less significant. Other factors, such as thin‐film microstructure, crystallinity, domain size, become more important in affecting the resulting device's charge transport. 相似文献
14.
D. W. Smith Jr. H. V. Shah K. P. U. Perera M. W. Perpall D. A. Babb S. J. Martin 《Advanced functional materials》2007,17(8):1237-1246
Bis‐ortho‐diynylarene (BODA) monomers, prepared from common bisphenols in three high yielding steps, undergo free‐radical‐mediated thermal polymerization via an initial Bergman cyclo‐rearrangement. Polymerization is carried out at 210 °C in solution or neat with large pre‐vitrification melt windows (4–5 h) to form branched oligomers containing reactive pendant and terminal aryldiynes. Melt‐ and solution‐processable oligomers with weight‐average molecular weight Mw = 3000–24 000 g mol–1 can be coated as a thin film or molded using soft lithography techniques. Subsequent curing to 450 °C affords network polymers with no detectable glass transition temperatures below 400 °C and thermal stability ranging from 0.5–1.5 % h–1 isothermal weight loss measured at 450 °C under nitrogen. Heating to 900–1000 °C gives semiconductive glassy carbon in high yield. BODA monomer synthesis, network characterization and kinetics, processability, thin‐film photoluminescence, and thermal properties are described. 相似文献
15.
Water‐Induced Scandium Oxide Dielectric for Low‐Operating Voltage n‐ and p‐Type Metal‐Oxide Thin‐Film Transistors 下载免费PDF全文
Ao Liu Guoxia Liu Huihui Zhu Huijun Song Byoungchul Shin Elvira Fortunato Rodrigo Martins Fukai Shan 《Advanced functional materials》2015,25(46):7180-7188
Solution‐processed metal‐oxide thin films based on high dielectric constant (k) materials have been extensively studied for use in low‐cost and high‐performance thin‐film transistors (TFTs). Here, scandium oxide (ScOx) is fabricated as a TFT dielectric with excellent electrical properties using a novel water‐inducement method. The thin films are annealed at various temperatures and characterized by using X‐ray diffraction, atomic‐force microscopy, X‐ray photoelectron spectroscopy, optical spectroscopy, and a series of electrical measurements. The optimized ScOx thin film exhibits a low‐leakage current density of 0.2 nA cm?2 at 2 MV cm?1, a large areal capacitance of 460 nF cm?2 at 20 Hz and a permittivity of 12.1. To verify the possible applications of ScOx thin films as the gate dielectric in complementary metal oxide semiconductor (CMOS) electronics, they were integrated in both n‐type InZnO (IZO) and p‐type CuO TFTs for testing. The water‐induced full oxide IZO/ScOx TFTs exhibit an excellent performance, including a high electron mobility of 27.7 cm2 V?1 s?1, a large current ratio (Ion/Ioff) of 2.7 × 107 and high stability. Moreover, as far as we know it is the first time that solution‐processed p‐type oxide TFTs based on a high‐k dielectric are achieved. The as‐fabricated p‐type CuO/ScOx TFTs exhibit a large Ion/Ioff of around 105 and a hole mobility of 0.8 cm2 V?1 at an operating voltage of 3 V. To the best of our knowledge, these electrical parameters are among the highest performances for solution‐processed p‐type TFTs, which represents a great step towards the achievement of low‐cost, all‐oxide, and low‐power consumption CMOS logics. 相似文献
16.
Dandan Shi Zitong Liu Jing Ma Zhiyuan Zhao Luxi Tan Gaobo Lin Jianwu Tian Xisha Zhang Guanxin Zhang Deqing Zhang 《Advanced functional materials》2020,30(21)
A novel building block, denoted as half‐fused diketopyrrolopyrrole (DPP) (9‐(3‐octadecylhenicosyl)‐8‐(thiophen‐2‐yl)‐7H‐pyrrolo[3,4‐a]thieno[3,2‐g]indolizine‐7,10(9H)‐dione), in which one of the flanking thiophene units is fused to one of the DPP rings via a carbon‐carbon double bond at the N‐position is reported. The half‐fused DPP is successfully utilized as an electron acceptor to prepare the conjugated donor–acceptor polymer PTFDFT , which exhibits ambipolar semiconducting behavior in ambient air. Theoretical calculations and absorption spectral studies show that the backbone of PTFDFT is more planar compared to the reference polymer with conventional DPP units. As a result, PTFDFT shows a narrow bandgap and low lowest unoccupied molecular orbital level. The more planar backbone with fewer side chains favors the dense packing of the polymer chains of PTFDFT with a short π–π stacking distance (3.49 Å). Grazing‐incidence wide‐angle X‐ray scattering data further confirm the predominant edge‐on packing mode of the PTFDFT polymer chains on the substrate. As expected, the PTFDFT thin film shows excellent ambipolar semiconducting properties under ambient conditions, reaching 2.23 and 1.08 cm2 V?1 s?1 for the n‐ and p‐channels, respectively. In addition, complementary‐like inverter with gain value as high as 141 is successfully constructed using the PTFDFT thin film. 相似文献
17.
Junying Liu Rui Zhang Itaru Osaka Sarada Mishra Anna E. Javier Detlef‐M. Smilgies Tomasz Kowalewski Richard D. McCullough 《Advanced functional materials》2009,19(21):3427-3434
New solution processable 4‐(2‐hexyldecan)‐4H‐bisthieno[2,3‐d:3′,2′‐b]pyrrole and 4,4′‐dialkyl‐2,2′‐bithiazole‐based copolymers (PBTzDTPs) are synthesized with excellent FET performance. These novel copolymers have considerable potential in printable electronics as they have high charge carrier mobilities, excellent air stability, good solution processibility, and no requirement for post‐deposition thermal annealing, all requirements for this field of application. The thin film transistors fabricated from PBTzDTPs achieve field effect mobilities as high as 0.14 cm2 V?1 s?1 with current on/off ratios up to 106 without thermal annealing. In addition, the devices exhibit stable performance in air, showing no significant degradation over 60 days. Moreover, the polymers described here provide an excellent example of the systems in which higher mobility performance does not require higher crystalline, long‐range ordered structures. Such a system appears to be particularly promising for rapid fabrication techniques, where kinetic conditions usually prevent the development of long‐range order. 相似文献
18.
All‐Solution‐Processed Indium‐Free Transparent Composite Electrodes based on Ag Nanowire and Metal Oxide for Thin‐Film Solar Cells 下载免费PDF全文
Areum Kim Yulim Won Kyoohee Woo Sunho Jeong Jooho Moon 《Advanced functional materials》2014,24(17):2462-2471
Fully solution‐processed Al‐doped ZnO/silver nanowire (AgNW)/Al‐doped ZnO/ZnO multi‐stacked composite electrodes are introduced as a transparent, conductive window layer for thin‐film solar cells. Unlike conventional sol–gel synthetic pathways, a newly developed combustion reaction‐based sol–gel chemical approach allows dense and uniform composite electrodes at temperatures as low as 200 °C. The resulting composite layer exhibits high transmittance (93.4% at 550 nm) and low sheet resistance (11.3 Ω sq‐1), which are far superior to those of other solution‐processed transparent electrodes and are comparable to their sputtered counterparts. Conductive atomic force microscopy reveals that the multi‐stacked metal‐oxide layers embedded with the AgNWs enhance the photocarrier collection efficiency by broadening the lateral conduction range. This as‐developed composite electrode is successfully applied in Cu(In1‐x,Gax)S2 (CIGS) thin‐film solar cells and exhibits a power conversion efficiency of 11.03%. The fully solution‐processed indium‐free composite films demonstrate not only good performance as transparent electrodes but also the potential for applications in various optoelectronic and photovoltaic devices as a cost‐effective and sustainable alternative electrode. 相似文献
19.
Layer‐by‐Layer Conjugated Extension of a Semiconducting Polymer for High‐Performance Organic Field‐Effect Transistor 下载免费PDF全文
Mi Jang Se Hyun Kim Han‐Koo Lee Yun‐Hi Kim Hoichang Yang 《Advanced functional materials》2015,25(25):3833-3839
A donor–acceptor (D–A) semiconducting copolymer, PDPP‐TVT‐29, comprising a diketopyrrolopyrrole (DPP) derivative with long, linear, space‐separated alkyl side‐chains and thiophene vinylene thiophene (TVT) for organic field‐effect transistors (OFETs) can form highly π‐conjugated structures with an edge‐on molecular orientation in an as‐spun film. In particular, the layer‐like conjugated film morphologies can be developed via short‐term thermal annealing above 150 °C for 10 min. The strong intermolecular interaction, originating from the fused DPP and D–A interaction, leads to the spontaneous self‐assembly of polymer chains within close proximity (with π‐overlap distance of 3.55 Å) and forms unexpectedly long‐range π‐conjugation, which is favorable for both intra‐ and intermolecular charge transport. Unlike intergranular nanorods in the as‐spun film, well‐conjugated layers in the 200 °C‐annealed film can yield more efficient charge‐transport pathways. The granular morphology of the as‐spun PDPP‐TVT‐29 film produces a field‐effect mobility (μ FET) of 1.39 cm2 V?1 s?1 in an OFET based on a polymer‐treated SiO2 dielectric, while the 27‐Å‐step layered morphology in the 200 °C‐annealed films shows high μ FET values of up to 3.7 cm2 V?1 s?1. 相似文献
20.
H. Nakanotani S. Akiyama D. Ohnishi M. Moriwake M. Yahiro T. Yoshihara S. Tobita C. Adachi 《Advanced functional materials》2007,17(14):2328-2335
By doping 2,7‐bis[4‐(N‐carbazole)phenylvinyl]‐9,9′‐spirobifluorene (spiro‐SBCz) into a wide energy gap 4,4′‐bis(9‐carbazole)‐2,2′‐biphenyl (CBP) host, we demonstrate an extremely low ASE threshold of Eth = (0.11 ± 0.05) μJ cm–2 (220 W cm–2) which is the lowest ASE threshold ever reported. In addition, we confirmed that the spiro‐SBCz thin film functions as an active light emitting layer in organic light‐emitting diode (OLED) and a field‐effect transistor (FET). In particular, we succeeded to obtain linear electroluminescence in the FET structure which will be useful for future organic laser diodes. 相似文献