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Large-scale fabrication of field-effect transistors based on solution-grown organic single crystals

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Science Bulletin 2015年第12期60卷 1122-1127,I0003页

作者： Shuang Liu Jia-Ke Wu Cong-Cheng Fan guo-biao xue Hong-Zheng Chen Huolin L. Xin Han-Ying Li Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization State Key Laboratory of Silicon Materials Department of Polymer Science and EngineeringZhejiang University Hangzhou 310027 China Center for Functional Nanomaterials Brookhaven National Laboratory New York NY 11973 USA

A simple solution processing method was de- veloped to grow large-scale well-aligned single crystals in- cluding 6,13-bis（triisopropylsilylethynyl）pentacene （TIPS- pentacene）, anthracene, tetracene, perylene, C6o and tetra- cyanoquinodimethane. As pinned by a solid needle, a droplet of semiconductor solution dried into single-crystal arrays on a 1 cm×2 cm substrate. TIPS-pentacene was used to demonstrate the fabrication of hundreds of field- effect transistors （FETs） with the hole mobility as high as 6.46 cm^2 V^-1.s^-1. As such, this work provides a high- throughput, yet efficient approach for statistical examination on the FET performance of organic single crystals.

关键词： Organic single-crystal transistors Large scale High mobility Solution process

Solution-grown aligned crystals of diketopyrrolopyrroles(DPP)-based small molecules:Rough surfaces and relatively low charge mobility

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Chinese Chemical Letters 2016年第4期27卷 523-526页

作者： Zhuo-Ting Huang Cong-Cheng Fan guo-biao xue Jia-Ke Wu Shuang Liu Huan-Bin Li Hong-Zheng Chen Han-Ying Li MOE Key Laboratory of Macromolecular Synthesis and Functionalization State Key Laboratory of Silicon Materials Department of Polymer Science and Engineering Zhejiang University

Field-effect transistors（FETs） of three diketopyrrolopyrroles（DPP）-based small molecules, 3,6-bis（5-phenylthiophene-2-yl）-2,5-bis（2-ethylhexyl）pyrrolopyrrole-1,4-dione（PDPPP）, 3,6-bis（5-（4-fluorophenyl）thiophene-2-yl）-2,5-bis（2-ethylhexyl）pyrrolo pyrrole-1,4-dione（FPDPPPF） and 3,6-bis（5-（4-n-butylphenyl）thiophene-2-yl）-2,5-bis（2-ethylhexyl）pyrrolo pyrrole-1,4-dione（Bu PDPPPBu）, have been studied in this work. Well aligned crystals of the three molecules were grown from para-xylene by droplet-pinned crystallization method. FETs based on these aligned crystals exhibit a hole mobility up to0.19 cm^2 V 1s 1and electron mobility up to 0.008 cm^2 V 1s 1. The achieved hole mobility is of the same order of magnitude as reported highest hole mobility for DPP-based small molecules, but it is much lower than that of the high-performance DPP-based polymers. The relative low mobility is mainly attributed to the rough crystal surfaces with steps and, thus, non-smooth charge transport channels at the interfaces between the crystals and the dielectrics. This work has implications for understanding the low charge mobility of DPP-based small molecules.

关键词： Diketopyrrolopyrrole Crystals Solution processing Organic field-effect transistors Morphology

Breaking the efficiency limitations of dissipative Kerr solitons using nonlinear couplers

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 88-94页

作者： Ming Li Xiao-Xiao xue Yan-Lei Zhang Xin-biao Xu Chun-Hua Dong Guang-Can guo Chang-Ling Zou CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China CAS Centerfor Excellence in Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China Department of Electronic Engineering Beijing National Research Center for Information Science and TechnologyTsinghua University Beijing 100084China

Dissipative Kerr solitons(DKS) have long been suffering from poor power conversion efficiency when driven by continuous-wave lasers. By deriving the critical coupling condition of a multimode nonlinear optics system in a generalized theoretical framework,two efficiency limitations of the conventional pump method of DKS are revealed: the effective coupling rate is too small and is also power-dependent. A general approach is provided to resolve this challenge by introducing two types of nonlinear couplers to couple the soliton cavity and CW input through nonlinear processes. The collective coupler opens multiple coupling channels and the self-adaptive coupler builds a power-independent effective external coupling rate to the DKS for approaching the generalized critical coupling condition, which promises near-unity power conversion efficiencies. For instance, a conversion efficiency exceeding 90% is predicted for aluminum nitride microrings with a nonlinear coupler utilizing second-harmonic generation. The mechanism applies to various nonlinear processes, including Raman and Brillouin scattering, and thus paves the way for micro-solitons toward practical applications.

关键词： Kerr frequency comb conversion efficiency nonlinear coupler

Electron transport in solution-grown TIPS-pentacene single crystals:Effects of gate dielectrics and polar impurities

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Chinese Chemical Letters 2016年第12期27卷 1781-1787页

作者： Zhuo-Ting Huang guo-biao xue Jia-Ke Wu Shuang Liu Huan-Bin Li Yu-Hui Yang Feng Yan Paddy K.L.Chan Hong-Zheng Chen Han-Ying Li MOE Key Laboratory of Macromolecular Synthesis and Functionalization State Key Laboratory of Silicon Materials Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China Department of Applied Physics and Materials Research Centre The Hong Kong Polytechnic University Hong Kong China Department of Mechanical Engineering The University of Hong Kong Hong Kong China

The n-channel behavior has been occasionally reported in the organic field-effect transistors （OFETs） that usually exhibit p-channel transport only. Reconfirmation and further examination of these unusual device performances should deepen the understanding on the electron transport in organic semiconductors. 6,13-bis（triisopropyl-silylethynyl） pentacene （TIPS-pentacene）, a widely examined p-channel material as Au is used for source-drain electrodes, has recently been reported to exhibit electron transport when grown from non-polar solvent on divinyltetramethyldisiloxanebis （benzocy- clobutene）（BCB） dielectric, spurring the study on this unusual electron transport. This paper describes FET characteristics of solution-grown TlPS-pentacene single crystals on five polymer gate dielectrics including polystyrene （PS）, poly（methyl methacrylate）（PMMA）, poly（4-vinyl phenol）（PVP）, poly（vinyl alcohol）（PVA） and poly（vinylidene fluoride-trifluoroethylene-chlorofluoroethylene）（P（VDF-TrFE-CFE））. In addition to the p-channel behavior, electron transport occurs in the crystals on PMMA, PS, thick PVA （40 nm） and a bilayer dielectric of PMMA on P（VDF-TrFE-CFE）, while does not on PVP and thin PVA （2 nm）. The two distinct FET characteristics are consistent with the previous reported trap effect of hydroxyl groups （in PVP and PVA） and reduced injection barrier by Na~ ions （as impurity in PVA）. The highest electron mobility of 0.48 cm2 V-1 s-1 has been achieved in the crystals on PMMA. Furthermore, the electron transport is greatly attenuated after the crystals are exposed to the vapor of a variety of polar solvents and the attenuated electron transport partially recovers if the crystals are heated, indicating the adverse effect of polar impurities on electron transport. By reconfirming the n-channel behavior in the OFETs based on TIPS-pentacene, this work has implications for the design of n-channel and ambipolar OFETs.

关键词： TIPS-pentacene single crystal Electron transport Polymer dielectric Polar solvent Organic field-effect transistor

Resonance mechanism of flapping wing based on fluid structure interaction simulation

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Chinese Journal of Aeronautics 2024年第5期37卷 243-262页

作者： Yueyang guo Wenqing YANG Yuanbo DONG Dong xue National Key Laboratory of Science and Technology on Aerodynamic Design and Research School of AeronauticsNorthwestern Polytechnical UniversityXi'an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518063China Yangtze River Delta Research Institute of Northwestern Polytechnical University Taicang 215400China

Certain insect species have been observed to exploit the resonance mechanism of their *** order to achieve resonance and optimize aerodynamic performance,the conventional approach is to set the flapping frequency of flexible wings based on the Traditional Structural Modal(TSM)***,there exists controversy among researchers regarding the relationship between frequency and aerodynamic *** that the structural response of wings can be influenced by the surrounding air vibrations,an analysis known as Acoustic Structure Interaction Modal(ASIM)is introduced to calculate the resonant *** this study,Fluid Structure Interaction(FSI)simulations are employed to investigate the aerodynamic performance of flapping wings at modal frequencies derived from both TSM and ASIM *** performance is evaluated for various mass ratios and frequency ratios,and the findings indicate that the deformation and changes in vortex structure exhibit similarities at mass ratios that yield the highest aerodynamic ***,the flapping frequency associated with the maximum time-averaged vertical force coefficient at each mass ratio closely aligns with the ASIM frequency,as does the frequency corresponding to maximum ***,the ASIM analysis can provide an effective means for predicting the optimal flapping frequency for flexible ***,it enables the prediction that flexible wings with varying mass ratios will exhibit similar deformation and vortex structure *** paper offers a fresh perspective on the ongoing debate concerning the resonance mechanism of Flexible Flapping Wings(FFWs)and proposes an effective methodology for predicting their aerodynamic performance.

关键词： Flexible Flapping Wing(FFW) Acoustic Structure Interaction Modal(ASIM) Fluid Structure Interaction(FSI) Resonance mechanism Aerodynamic performance

Improving mathematical model of burden distribution and correcting chute angle to cope with fluctuation of stock line

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Journal of Iron and Steel Research International 2024年第2期31卷 342-356页

作者： Jian-sheng Chen Wen-guo Liu Hao guo Wang Ding Qing-guo xue Jing-song Wang Hai-bin Zuo State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing100083China MCC Capital Engineering&Research Incorporation Limited Beijing100176China Hunan Valin Xiangtan Iron and Steel Co. Ltd.Xiangtan411101HunanChina

Accurate evaluations of the burden distribution are of critical importance to stabilize the operation of blast *** mathematical model and discrete element method(DEM)are two attractive methods for predicting burden *** on DEM,the initial velocities of the pellet,sinter,and coke were calculated,and the velocity attenuations of the above three particles between the burden and the chute were *** initial velocity and velocity attenuation were applied to a mathematical model for improving the ***,based on the improved model,a scheme for rectifying the chute angles was proposed to address the fluctuation of the stock line and maintain a stable burden *** validity of the scheme was confirmed via a stable burden distribution under different stock *** mathematical model has been successfully applied to evaluate the online burden distribution and cope with the fluctuation of the stock line.

关键词： Burden distribution Mathematical model Discrete element method Velocity attenuation Stock line fluctuation

Multicolor emission from lanthanide ions doped lead-free Cs_(3)Sb_(2)Cl_(9) perovskite nanocrystals

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Journal of Rare Earths 2024年第5期42卷 940-946,I0005页

作者： He Shao Lifang Li Xiufeng Wu Lin Xu biao Dong Donglei Zhou xue Bai Hongwei Song State Key Laboratory of Organic Electronics and Information Displays&Institute of Advanced Materials College of Materials Science and EngineeringNanjing University of Posts&TelecommunicationsNanjing210023China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and Engineering Jilin UniversityChangchun130012China

The toxicity of lead ions has become the severe challenge for the all-inorganic lead halide p erovskite materials,although some works have rep orted the lead-free perovskite nanocrystals(NCs),the photoluminescence quantum yield(PLQY)of these materials is still ***,because the halogen ions can be easily exchanged,the controllable multicolor emission in perovskite NCs is difficult to realize in current *** this work,we introduced lanthanide ions into lead-free Cs_(3)Sb_(2)Cl_(9) perovskite *** from the energy transfer between Cs_(3)Sb_(2)Cl_(9) perovskite NC host and lanthanide ions,the multicolor emission was *** on controlling the doping concentration of Tb^(3+)and Eu^(3+)ions,the white light emission under UV excitation would be turned easily in the Tb^(3+)/Eu^(3+)codoped *** addition,efficient energy transfer from perovskite NCs to Tb^(3+)or Eu^(3+)ions is beneficial to improving the optical properties of lead-free perovskite NCs,resulting in maximum PLQYs of red,green and white light emission of 22.6%,19.7%and 28.5%,***,a white light emitting device(WLED)was fabricated with a power efficiency of 18.5 lm/W,which presents the Commission Internationale de l'Eclairage(CIE)of(0.33,0.35).

关键词： Perovskite nanocrystals Lead free Lanthanide ions Energy transfer White light emitting device Rare earths

Effect of slag composition on kinetic behavior of deep deoxidation of 5 wt.% Si high-silicon austenitic stainless steel

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Journal of Iron and Steel Research International 2024年第8期31卷 1873-1885页

作者： Guan-xiong Dou Han-jie guo Jing guo xue-cheng Peng Qing-yun Chen School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing 100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing 100083China

Based on a thermodynamic study of 5 wt.%Si high-silicon austenitic stainless steel(SS-5Si)smelting using CaF_(2)-CaO-Al_(2)0_(3)-Mg-Si0_(2) slag to obtain a low oxygen content of less than 10×10^(-4) wt.%,a kinetic mass transfer model for deep deoxidation was established through laboratory studies,and the effects of slag components and temperature on deoxidation during the slag-steel reaction process of sS-5Si were systematically *** experimental data verified the accuracy of the model *** results showed that the final oxygen content in the steel at 1873 K was mainly controlled by the oxygen content derived from the activity of SiO_(2) regulated by the[Si]-[O]equilibrium reaction in the slag system;in particular,when the slag basicity R(R=w(CaO)/w(SiO2),where w(CaO)and w(SiO_(2))are the contents of CaO and SiO_(2) in the slag,respectively)is 3,the Al2O3 content in the slag needs to be less than 2.7%.The mass transfer rate equation for the kinetics of the deoxidation reaction revealed that the mass transfer of oxygen in the liquid metal is the rate-controlling step under different slag conditions at 1873 K,and the oxygen transfer coefficient ko.m increases with increasing the slag basicity from 4.0×10^(-6)m s^(-1)(R=1)to 4.3×10^(-5) m s^(-1)(R=3).ko.m values at R=2 and R=3 are almost the same,indicating that high slag basicity has little *** integral of the mass transfer rate equation for the deoxidation reaction of SS-5Si under different slag conditions is *** total oxygen content of the molten steel decreases with increasing basicity from an initial content of 22×10^(-4) to 3.2×10^(-4) wt.%(R=3),consistent with the change in ko.m with slag *** R=2,the slag-steel reaction takes 15 min to reach equilibrium(w[O]=5.5×10^(-4) wt.%),whereas at R=3,the slag-steel reaction takes 30 min to reach equilibrium(w[0]=3.2×10^(-4) wt.%).Considering the depth of deoxidation and reaction time of SS-5Si smelting,it is recommended the slag b

关键词： Slag-steel reaction Kinetics Rate-controlling step Deep deoxidation Transfer coefficient

Path Planning for AUVs Based on Improved APF-AC Algorithm

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Computers, Materials & Continua 2024年第3期78卷 3721-3741页

作者： guojun Chen Danguo Cheng Wei Chen xue Yang Tiezheng guo Industrial Center Nanjing Institute of TechnologyNanjing211167China

With the increase in ocean exploration activities and underwater development,the autonomous underwater vehicle(AUV)has been widely used as a type of underwater automation equipment in the detection of underwater ***,nowadays AUVs generally have drawbacks such as weak endurance,low intelligence,and poor detection *** research and implementation of path-planning methods are the premise of AUVs to achieve actual *** improve the underwater operation ability of the AUV,this paper studies the typical problems of path-planning for the ant colony algorithm and the artificial potential field *** response to the limitations of a single algorithm,an optimization scheme is proposed to improve the artificial potential field ant colony(APF-AC)*** with traditional ant colony and comparative algorithms,the APF-AC reduced the path length by 1.57%and 0.63%(in the simple environment),8.92%and 3.46%(in the complex environment).The iteration time has been reduced by approximately 28.48%and 18.05%(in the simple environment),18.53%and 9.24%(in the complex environment).Finally,the improved APF-AC algorithm has been validated on the AUV platform,and the experiment is consistent with the *** APF-AC algorithm can effectively reduce the underwater operation time and overall power consumption of the AUV,and shows a higher safety.

关键词： Path-planning autonomous underwater vehicle ant colony algorithm artificial potential field bio-inspired neural network