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51.
《Organic Electronics》2014,15(7):1317-1323
Aligned single-crystalline organic nanowires (NWs) show promising applications in flexible and stretchable electronics, while the use of pre-existing aligned techniques and well-developed photolithography techniques are impeded by the large incompatibility with organic materials and flexible substrates. In this work, aligned copper phthalocyanine (CuPc) organic NWs were grown on flexible and transparent poly(dimethylsiloxane) (PDMS) substrate via a grating-assisted growth approach. Furthermore, a simple yet efficient etching-assisted transfer printing (ETP) method was used to achieve CuPc NW array-based flexible top-gate organic field-effect transistors (OFETs) with a high mobility up to 2.0 cm2 V−1 s−1, a small operating voltage within ±10 V, a high on/off ratio >104, and excellent bend stability with bending radius down to 3 mm. It is expected that the high-performance organic NW array-based top-gate OFETs with exceeding bend stability will have important applications in future flexible electronics. 相似文献
52.
《Organic Electronics》2014,15(7):1476-1480
For window integration of semi-transparent solar cells in living and working areas, color neutral transparency perception and good color rendering are of pivotal importance. In order to tune the optical device properties, we simulate a parallel tandem configuration with two different absorber materials. Within a regime of convenient transparency perception, the transparency can be adjusted between 20% and 40% by choosing the right absorber layer thickness combination. From the optical field in the tandem devices we calculate the charge carrier generation profile and subsequently correlate the optical properties with the electrical device properties as derived from drift-diffusion modelling – altogether allowing for a comprehensive assessment of the transparency, the transparency perception and the device performance and their interdependencies. 相似文献
53.
《Organic Electronics》2014,15(8):1717-1723
We have investigated the growth behavior and water vapor permeation barrier properties of cyclic chemical vapor deposition (C-CVD)-grown 10-nm-thick single layer of Al2O3. Al2O3 layers grown by C-CVD showed a high density of 3.298 g/cm3 and were amorphous without grain boundaries. A deposition rate of 0.46 nm/cycle was obtained. The C-CVD system was self-limiting, as in the case of atomic layer deposition, which enables precise control of the thickness of the Al2O3 layer. A water vapor transmission rate of 1.51 × 10−5 (g/m2)/day was obtained from a Ca degradation test performed at 85 °C and 85% relative humidity. Moreover, the performance of organic light-emitting diodes, passivated by a C-CVD-grown 10-nm-thick Al2O3 single layer, was not affected after 24,000 h of turn-on time; this is strong evidence that C-CVD-grown Al2O3 layers effectively prevent water vapor from diffusing into the active organic layer. 相似文献
54.
介绍了“铁碳微电解+厌氧/缺氧/好氧生化处理法+膜生物反应器”工艺在印制电路板COD废水处理中的应用,其中包括各部分作用原理、主要运行参数以及主要处理效果。工艺运行结果表明,当设备运行正常的情况下,废水COD降解率可达95%,出水COD可达50mg/L,达到排放标准。 相似文献
55.
Solution-processed organic ferroelectric resistive switches could become the long-missing non-volatile memory elements in organic electronic devices. To this end, data retention in these devices should be characterized, understood and controlled. First, it is shown that the measurement protocol can strongly affect the ‘apparent’ retention time and a suitable protocol is identified. Second, it is shown by experimental and theoretical methods that partial depolarization of the ferroelectric is the major mechanism responsible for imperfect data retention. This depolarization occurs in close vicinity to the semiconductor-ferroelectric interface, is driven by energy minimization and is inherently present in this type of phase-separated polymer blends. Third, a direct relation between data retention and the charge injection barrier height of the resistive switch is demonstrated experimentally and numerically. Tuning the injection barrier height allows to improve retention by many orders of magnitude in time, albeit at the cost of a reduced on/off ratio. 相似文献
56.
A solvent-free lift-off method has been introduced to fabricate the aluminum nano-hole array with diameter down to 80 nm as the base electrode for a vertical organic transistor. The imprinted vertical organic transistor exhibited base leakage current density as low as 5 × 10−5 mA/cm2 and high ON/OFF current ratio as high as 105. 相似文献
57.
Based on ultrathin dinaphtho[3,4-d:3′,4′-d′]benzo[1,2-b:4,5-b′]dithiophene (Ph5T2) single-crystal microplates, the highly sensitive organic field-effect H2S sensors are realized at room temperature. The response is as high as 1.2 × 106% in 50 ppm H2S. This value is extremely high for H2S sensors, and is three orders of magnitude higher than that of the most reported semiconductor gas sensors. The response/recovery time is respectively as low as 2 min and 1 min in 50 ppm H2S. The detect limitation is as low as 0.5 ppm. The ultrathin single-crystal microplates provide direct and efficient ways for the analytes' activities within the conducting channel, and therefore mainly account for the improved sensing performance. The excellent sensing performance of ultrathin Ph5T2 single-crystal microplate transistors reveals the capacity of developing highly sensitive room-temperature sensors. 相似文献
58.
Synthetic approaches for optimizing polymer-based organic photodiodes (OPDs) by systematically analyzing the effects of the hole-blocking layer, the electron-blocking layer, and the thickness and morphology of the active layer with respect to the dark current and detectivity have been reported. PBDTT-DPP with a repeating alkylthienylbenzodithiophene (BDTT) and diketopyrrolopyrrole (DPP) units is used as a p-type polymer for achieving both broadband absorption and a high absorption coefficient in conjunction with n-type [6,6]-phenyl C70 butyric acid methyl ester (PC70BM) for constructing photoactive layers. Through systematic investigations of various interfacial layers, we found that the thickness of the active layer and the energy level of the hole/electron blocking layer were critical for minimizing the dark current of OPDs. By changing the deposition method of the PBDTT-DPP/PC70BM blend and using post treatment, we discovered that the morphology of the active layer was directly related to the photocurrent of OPDs. Furthermore, we conducted a comparative study between a bulk heterojunction and a planar heterojunction (PHJ) to demonstrate the effectiveness of the PHJ for suppressing the dark current. Consequently, we realized a high detectivity of 5.3 × 1012 Jones with an optimized device architecture and morphology. This work shows the importance of a synthetic approach for optimizing OPDs that requires both a high photocurrent and a low dark current in the reverse saturation regime. 相似文献
59.
R.C. Hiorns R. deBettignies J. Leroy S. Bailly M. Firon C. Sentein A. Khoukh H. Preud'homme C. Dagron‐Lartigau 《Advanced functional materials》2006,16(17):2263-2273
A series of poly(3‐hexylthiophene)s (P3HTs) and poly(3‐butylthiophene)s (P3BTs) with predetermined molecular weights and varying polydispersities are prepared using a simplified Grignard metathesis chain‐growth polymerization. Techniques were elaborated to prepare extremely high molecular weight P3HT (number‐average molecular weight of around 280 000 g mol–1) with a low polydispersity (< 1.1) without resorting to fractionation. Optimization of the annealing of a series of solar cells based on blends of poly(3‐alkylthiophene)s (P3ATs) and [6,6]‐phenyl C61 butyric acid methyl ester indicates that the polydispersities, molecular weights, and degrees of conjugation of the P3ATs all have an important impact not only on cell characteristics but also on the most effective annealing temperature required. The results indicate that each cell requires annealing treatments specific to the type of polymer and its molecular weight distribution. 相似文献
60.
This investigation discusses a structural phase transition of organic crystalline phenanthrene and the resulting changes of its electronic and optical properties investigated by ab initio calculations based on density functional theory (DFT). The structure of phase I has been optimized then its electronic and optical properties have been calculated. Our computational results on phase I (at ambient pressure) get along well with the available experimental data.Calculating the electronic and optical properties of phase II are proceeded in the same way and the results, particulary Raman spectra, reveal a crystallographic phase transition indicated by abrupt changes in lattice constants which are accompanied by rearrangement of the molecules. This results in modifications of the electronic structure and optical response. For both phases the band dispersion of the valence and conduction bands are anisotropic, whereas the band splitting is strongly noticeable in phase II. By calculating the imaginary part of the dielectric function of phase II, we have found the appearance of new peaks at the lowest z-polarized absorption and about 30 eV in all absorption components. Excitonic effects in the optical properties of phases I and II have been investigated by solving the Bethe–Salpeter equation (BSE) on the basis of the FPLAPW method. Phase II shows four main excitonic structures in the energy range below band gap, whereas phase I shows two. The excitonic structures in the optical spectra of phase II show a red shift in comparison to phase I. The calculated binding energies of spin-singlet excitons in phase II are larger than the ones in phase I. 相似文献