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Porous materials are widely employed in a large range of applications, in particular, for storage, separation, and catalysis of fine chemicals. Synthesis, characterization, and pre- and post-synthetic computer simulations are mostly carried out in a piecemeal and ad hoc manner. Whilst high throughput approaches have been used for more than 30 years in the porous material fields, routine integration of experimental and computational processes is only now becoming more established. Herein, important developments are highlighted and emerging challenges for the community identified, including the need to work toward more integrated workflows.  相似文献   

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The low dimensionality of organic superconductors leads to pronounced anisotropy in the upper critical field. In the vicinity of the field direction parallel to the superconducting plane, the critical field shoots out due to the suppression of the orbital pair-breaking effect. Organic superconductors are suitable for the study of the high-field state related to the spin effect under an aligned field, since they are of a high crystalline quality. The reported experimental results covering the behavior at low temperatures are reviewed first, and the breakthrough of the BCS Pauli paramagnetic limit is discussed. The potential of the low-dimensional organic superconductor for study of the effect of electronic spectrum quantization is argued.  相似文献   

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Fabricating solar cells with tandem structure is an efficient way to broaden the photon response range without further increasing the thermalization loss in the system. In this work, a tandem organic solar cell (TOSC) based on highly efficient nonfullerene acceptors (NFAs) with series connection type is demonstrated. To meet the different demands of front and rear sub‐cells, two NFAs named F‐M and NOBDT with a whole absorption range from 300 to 900 nm are designed, when blended with wide bandgap polymer poly[(2,6‐(4,8‐bis(5‐(2‐ethylhexyl)thiophen‐2‐yl)‐benzo[1,2‐b:4,5‐b′]dithiophene))‐alt‐(5,5‐(1′,3′‐di‐2‐thienyl‐5′,7′‐bis(2‐ethylhexyl)benzo[1′,2′‐c:4′,5′‐c′]dithiophene‐4,8‐dione))] (PBDB‐T) and narrow bandgap polymer PTB7‐Th, respectively, the PBDB‐T: F‐M system exhibits a high Voc of 0.98 V and the PTB7‐Th: NOBDT system shows a remarkable Jsc of 19.16 mA cm?2, which demonstrate their potential in the TOSCs. With the guidance of optical simulation, by systematically optimizing the thickness of each layer in the TOSC, an outstanding power conversion efficiency of 14.11%, with a Voc of 1.71 V, a Jsc of 11.72 mA cm?2, and a satisfactory fill factor of 0.70 is achieved; this result is one of the top efficiencies reported to date in the field of organic solar cells.  相似文献   

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Lithium-metal batteries (LMBs) with high energy densities are highly desirable for energy storage, but generally suffer from dendrite growth and side reactions in liquid electrolytes; thus the need for solid electrolytes with high mechanical strength, ionic conductivity, and compatible interface arises. Herein, a thiol-branched solid polymer electrolyte (SPE) is introduced featuring high Li+ conductivity (2.26 × 10−4 S cm−1 at room temperature) and good mechanical strength (9.4 MPa)/toughness (≈500%), thus unblocking the tradeoff between ionic conductivity and mechanical robustness in polymer electrolytes. The SPE (denoted as M-S-PEGDA) is fabricated by covalently cross-linking metal–organic frameworks (MOFs), tetrakis (3-mercaptopropionic acid) pentaerythritol (PETMP), and poly(ethylene glycol) diacrylate (PEGDA) via multiple C S C bonds. The SPE also exhibits a high electrochemical window (>5.4 V), low interfacial impedance (<550 Ω), and impressive Li+ transference number (tLi+ = 0.44). As a result, Li||Li symmetrical cells with the thiol-branched SPE displayed a high stability in a >1300 h cycling test. Moreover, a Li|M-S-PEGDA|LiFePO4 full cell demonstrates discharge capacity of 143.7 mAh g−1 and maintains 85.6% after 500 cycles at 0.5 C, displaying one of the most outstanding performances for SPEs to date.  相似文献   

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A key breakthrough in inorganic modern electronics is the energy‐band engineering that plays important role to improve device performance or develop novel functional devices. A typical application is high electron mobility transistors (HEMTs), which utilizes 2D electron gas (2DEG) as transport channel and exhibits very high electron mobility over traditional field‐effect transistors (FETs). Recently, organic electronics have made very rapid progress and the band transport model is demonstrated to be more suitable for explaining carrier behavior in high‐mobility crystalline organic materials. Therefore, there emerges a chance for applying energy‐band engineering in organic semiconductors to tailor their optoelectronic properties. Here, the idea of energy‐band engineering is introduced and a novel device configuration is constructed, i.e., using quantum well structures as active layers in organic FETs, to realize organic 2DEG. Under the control of gate voltage, electron carriers are accumulated and confined at quantized energy levels, and show efficient 2D transport. The electron mobility is up to 10 cm2 V?1 s?1, and the operation mechanisms of organic HEMTs are also argued. Our results demonstrate the validity of tailoring optoelectronic properties of organic semiconductors by energy‐band engineering, offering a promising way for the step forward of organic electronics.  相似文献   

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Morphology tuning of the blend film in organic solar cells (OSCs) is a key approach to improve device efficiencies. Among various strategies, solid additive is proposed as a simple and new way to enable morphology tuning. However, there exist few solid additives reported to meet such expectations. Herein, chlorine-functionalized graphdiyne (GCl) is successfully applied as a multifunctional solid additive to fine-tune the morphology and improve device efficiency as well as reproductivity for the first time. Compared with 15.6% efficiency for control devices, a record high efficiency of 17.3% with the certified one of 17.1% is obtained along with the simultaneous increase of short-circuit current (Jsc) and fill factor (FF), displaying the state-of-the-art binary organic solar cells at present. The redshift of the film absorption, enhanced crystallinity, prominent phase separation, improved mobility, and decreased charge recombination synergistically account for the increase of Jsc and FF after introducing GCl into the blend film. Moreover, the addition of GCl dramatically reduces batch-to-batch variations benefiting mass production owing to the nonvolatile property of GCl. All these results confirm the efficacy of GCl to enhance device performance, demonstrating a promising application of GCl as a multifunctional solid additive in the field of OSCs.  相似文献   

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高强、高模、超粗旦聚乙烯醇(PVA)纤维的研制   总被引:3,自引:0,他引:3  
本文介绍了应用凝胶纺丝技术制备用于混凝土增强,力学性能很好的PVA粗旦纤维。研究了凝固浴温度、萃取条件和拉伸条件等对纤维结构和力学性能的影响,结果表明,凝胶纤维的性能与纺丝和拉伸工艺等有较大的关系。  相似文献   

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In recent years, superamphiphobic coatings have attracted world‐wide interest. In particular, those with high transmittance are of great interest as they significantly expand the range of applications of superamphiphobic coatings. This article reviews the recent development in the design and fabrication of superamphiphobic coatings with high transmittance, and clarifies technological challenges facing their practical applications. Finally, an outlook is made toward their future prospects.  相似文献   

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Organic electrochemical transistors (OECTs) are highly attractive for applications ranging from circuit elements and neuromorphic devices to transducers for biological sensing, and the archetypal channel material is poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate), PEDOT:PSS. The operation of OECTs involves the doping and dedoping of a conjugated polymer due to ion intercalation under the application of a gate voltage. However, the challenge is the trade‐off in morphology for mixed conduction since good electronic charge transport requires a high degree of ordering among PEDOT chains, while efficient ion uptake and volumetric doping necessitates open and loose packing of the polymer chains. Ionic‐liquid‐doped PEDOT:PSS that overcomes this limitation is demonstrated. Ionic‐liquid‐doped OECTs show high transconductance, fast transient response, and high device stability over 3600 switching cycles. The OECTs are further capable of having good ion sensitivity and robust toward physical deformation. These findings pave the way for higher performance bioelectronics and flexible/wearable electronics.  相似文献   

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利用电子扫描电镜、拉伸仪、耐疲劳性能试验机等分析测试方法研究铅浴等温淬火工艺对超细高强高碳钢丝组织和力学性能的影响。结果表明:对含碳量0.92%、直径Φ0.84mm的钢丝,升高加热温度、降低铅浴温度、提高过冷度有利于奥氏体化均匀,促进珠光体转变,导致先共析铁素体和二次网状渗碳体减少、珠光体片层间距减小、晶粒尺寸约20~30μm,后道湿拉拔至直径Φ0.12mm,断丝率降低至4~7次/t,钢丝最终强度达4080MPa。  相似文献   

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高导电高耐磨铜基材料研究进展   总被引:2,自引:0,他引:2  
介绍了几种主要高导电高耐磨铜基材料,指出添加石墨、陶瓷颗粒和合金元素可以提高材料的耐磨性,而导电率仍维持在较高水平,并对几种材料的增强机理作了初步探讨。回顾了近年来高导电高耐磨铜基材料的主要研究成果,并指出多元微合金化、基体纯化和晶粒细化、高度致密化为今后研究发展的方向。  相似文献   

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Al与cBN在高温高压下的相互作用   总被引:3,自引:0,他引:3  
将立方氮化硼(cBN)微粉和铝(Al)微粉按照体积比7:3的比例进行混配, 在高温(1300~1500℃)、高压(5.5GPa)条件下进行烧结. 利用X射线衍射分析(XRD)、透射电子显微镜(TEM)以及X射线色散能谱(EDS)对烧结体的物相构成、显微结构以及各组分元素的分布进行了分析. 实验结果表明, 1300℃, Al尚未与cBN反应; 当温度升至1400℃时, Al与cBN反应生成AlN和AlB2; 温度进一步升高至1500℃, 反应产物增多, 产物种类不变. TEM和EDS分析表明, 在反应过程中Al扩散进入cBN的表层, B扩散进入富Al的区域, 生成新相AlN和AlB2.  相似文献   

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高强度、高电导率铜基合金材料的研究现状及发展   总被引:1,自引:0,他引:1  
徐洪辉  杜勇  陈海林  潘竹  熊伟 《材料导报》2004,18(10):37-40
对高强度、高电导率铜基合金的研究现状进行了综述.经时效沉淀强化的合金显微组织结构好,强化效率高;快速凝固技术的运用可以大幅度地提高沉淀元素在Cu中的固溶度值,从而使铜基合金在电导率不显著降低的条件下,强度大幅度提高.近年来,国内外对原住加工的铜基复合材料MMCs进行了大量的研究工作,但在合金的最佳组成和实用化生产工艺方面还有待作更多和更深入的研究.  相似文献   

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