bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tuning Contact Resistance in Top‐Contact p‐Type and n‐Type Organic Field Effect Transistors by Self‐Generated Interlayers
Authors: Sarkar Tanmoy , Shamieh Basel , Verbeek Roy , Kronemeijer Auke Jisk , Gelinck Gerwin H. , Frey Gitti L. 
Published: January 2019

AbstractContact resistance significantly limits the performance of organic field‐effect transistors (OFETs). Positioning interlayers at the metal/organic interface can tune the effective work‐function and reduce contact resistance. Myriad techniques offer interlayer processing onto the metal pads in bottom‐contact OFETs. However, most methods are not suitable for deposition on organic films and incompatible with top‐contact OFET architectures. Here, a simple and versatile methodology is demonstrated for interlayer processing in both p‐ and n‐type devices that is also suitable for top‐contact OFETs. In this approach, judiciously selected interlayer molecules are co‐deposited as additives in the semiconducting polymer active layer. During top contact deposition, the additive molecules migrate from within the bulk film to the organic/metal interface due to additive‐metal interactions. Migration continues until a thin continuous interlayer is completed. Formation of the interlayer is confirmed by X‐ray photoelectron spectroscopy (XPS) and cross‐section scanning transmission electron microscopy (STEM), and its effect on contact resistance by device measurements and transfer line method (TLM) analysis. It is shown that self‐generated interlayers that reduce contact resistance in p‐type devices, increase that of n‐type devices, and vice versa, confirming the role of additives as interlayer materials that modulate the effective work‐function of the organic/metal interface.
Heat‐Assisted Photoacidic Oxidation Method for Tailoring the Surface Chemistry of Polymer Dielectrics for Low‐Power Organic Soft Electronics
Authors: Kim Jinsung , Kang Boseok , Cho Kilwon 
Published: January 2019

AbstractThe use in low‐power soft electronics of the appropriate insulating polymer materials with a high dielectric constant (k) is considered a practical alternative to that of inorganic dielectric materials, which are brittle and have high processing temperatures. However, the polar surfaces of typical high‐k polymer insulators are problematic. Further, it is a huge challenge to control their surface properties without damage because of their soft and chemically fragile nature. Here, a heat‐assisted photoacidic oxidation method that can be used to effectively oxidize the outermost surfaces of high‐k rubbery polymer films without degradation is presented. The oxidized surfaces prepared with the developed method contain large numbers of hydroxyl groups that enable the subsequent growth of dense and ordered self‐assembled monolayers (SAMs) consisting of organosilanes. The whole process modifies the surface characteristics of polymer dielectrics effectively. The mechanisms of the oxidation of polymer surfaces and the subsequent SAM growth process are investigated. The resulting surface‐tailored rubbery dielectrics exhibit superior electrical characteristics when used in organic transistors. These results demonstrate that this method can be used to realize practical soft organic electronics based on high‐k polymer dielectrics.
Semimetallicity and Negative Differential Resistance from Hybrid Halide Perovskite Nanowires
Authors: Khan Muhammad Ejaz , Lee Juho , Byeon Seongjae , Kim Yong‐Hoon 
Published: January 2019

AbstractIn the rapidly progressing field of organometal halide perovskites, the dimensional reduction can open up new opportunities for device applications. Herein, taking the recently synthesized trimethylsulfonium lead triiodide (CH3)3SPbI3 perovskite as a representative example, first‐principles calculations are carried out and the nanostructuring and device application of halide perovskite nanowires are studied. It is found that the 1D (CH3)3SPbI3 structure is structurally stable, and the electronic structures of higher‐dimensional forms are robustly determined at the 1D level. Remarkably, due to the face‐sharing [PbI6] octahedral atomic structure, the organic ligand‐removed 1D PbI3 frameworks are also found to be stable. Moreover, the PbI3 columns avoid the Peierls distortion and assume a semimetallic character, contradicting the conventional assumption of semiconducting metal‐halogen inorganic frameworks. Adopting the bundled nanowire junctions consisting of (CH3)3SPbI3 channels with sub‐5 nm dimensions sandwiched between PbI3 electrodes, high current densities and large room‐temperature negative differential resistance (NDR) are finally obtained. It will be emphasized that the NDR originates from the combination of the near‐Ohmic character of PbI3‐(CH3)3SPbI3 contacts and a novel NDR mechanism that involves the quantum‐mechanical hybridization between channel and electrode states. This work demonstrates the great potential of low‐dimensional hybrid perovskites toward advanced electronic devices beyond actively pursued photonic applications.
Synthesis and Properties of Plasmonic Boron‐Hyperdoped Silicon Nanoparticles
Authors: Rohani Parham , Banerjee Soham , Sharifi‐Asl Soroosh , Malekzadeh Mohammad , Shahbazian‐Yassar Reza , Billinge Simon J. L. , Swihart Mark T. 
Published: January 2019

AbstractElectronic properties of silicon, the most important semiconductor material, are controlled through doping. The range of achievable properties can be extended by hyperdoping, i.e., doping to concentrations beyond the nominal equilibrium solubility of the dopant. Here, hyperdoping is achieved in a laser pyrolysis reactor capable of providing nonequilibrium conditions, where doping is governed by kinetics rather than thermodynamics. High resolution scanning transmission electron microscopy (TEM) with energy‐dispersive X‐ray spectroscopy shows that the boron atom distribution in the hyperdoped nanoparticles is relatively uniform. The hyperdoped nanoparticles demonstrate tunable localized surface plasmon resonance (LSPR) and are stable in air for periods of at least one year. The hyperdoped nanoparticles are also stable upon annealing at temperatures up to 600 °C. Furthermore, boron hyperdoping does not change the diamond cubic crystal structure of silicon, as demonstrated in detail by high flux synchrotron X‐ray diffraction and pair distribution function (PDF) analysis, supported by high‐resolution TEM analysis.
Metal–Organic Frameworks Derived from Zero‐Valent Metal Substrates: Mechanisms of Formation and Modulation of Properties
Authors: Kim Jieun , Lee Seungju , Kim Jaesung , Lee Doohwan 
Published: January 2019

AbstractThe replicative construction of metal–organic frameworks (MOFs) templated with solvent‐insoluble solid substrates is of marked importance, as it allows for the assembly of 2D and 3D macro‐ and mesoscopic architectures with properties that are challenging to attain by the conventional solution‐based synthesis approach. This work reports an in situ and direct construction of MOFs from zero‐valent metal substrates via a green hydrothermal oxidation–MOF construction chemistry without the use of any additional metal source, chemical reagents, or acidification of solvent, and elucidates the zero‐valent metal derived formation mechanisms of MOFs and their structure modulation to 1D nanofibers (NFs), 2D film, and 3D core–shell microstructures. Through modulation of the competing surface oxidation‐dissolution and MOF crystallization kinetics, Al@MIL‐53 core–shell microstructures and MIL‐53 (Al) NFs are obtained that exhibit unique morphologies and marked properties superior to the conventional MIL‐53 (Al) powders. The generality of zero‐valent metal‐templated synthesis of MOFs is demonstrated with formation of MIL‐53 (Al), HKUST‐1, and ZIF‐7 polycrystalline films on Al, Cu, and Zn metal meshes, elucidating the significance of the approach utilizing solid metal substrate that can be easily processed into various shapes, architectures, and compositions.
Origins of High Performance and Degradation in the Mixed Perovskite Solar Cells
Authors: Heo Sung , Seo Gabseok , Lee Yonghui , Seol Minsu , Kim Seong Heon , Yun Dong‐Jin , Kim Yongsu , Kim Kihong , Lee Junho , Lee Jooho , Jeon Woo Sung , Shin Jai Kwang , Park Jucheol , Lee Dongwook , Nazeeruddin Mohammad Khaja 
Published: January 2019

AbstractThe origins of the high device performance and degradation in the air are the greatest issues for commercialization of perovskite solar cells. Here this study investigates the possible origins of the mixed perovskite cells by monitoring defect states and compositional changes of the perovskite layer over the time. The results of deep‐level transient spectroscopy analysis reveal that a newly identified defect formed by Br atoms exists at deep levels of the mixed perovskite film, and its defect state shifts when the film is aged in the air. The change of the defect state is originated from loss of the methylammonium molecules of the perovskite layer, which results in decreased JSC, deterioration of the power conversion efficiency and long‐term stability of perovskite solar cells. The results provide a powerful strategy to diagnose and manage the efficiency and stability of perovskite solar cells.
High‐Performance Flexible Freestanding Anode with Hierarchical 3D Carbon‐Networks/Fe7S8/Graphene for Applicable Sodium‐Ion Batteries
Authors: Chen Weihua , Zhang Xixue , Mi Liwei , Liu Chuntai , Zhang Jianmin , Cui Shizhong , Feng Xiangming , Cao Yuliang , Shen Changyu 
Published: January 2019

AbstractSodium‐ion batteries (SIBs) have gained tremendous interest for grid scale energy storage system and power energy batteries. However, the current researches of anode for SIBs still face the critical issues of low areal capacity, limited cycle life, and low initial coulombic efficiency for practical application perspective. To solve this issue, a kind of hierarchical 3D carbon‐networks/Fe7S8/graphene (CFG) is designed and synthesized as freestanding anode, which is constructed with Fe7S8 microparticles well‐welded on 3D‐crosslinked carbon‐networks and embedded in highly conductive graphene film, via a facile and scalable synthetic method. The as‐prepared freestanding electrode CFG represents high areal capacity (2.12 mAh cm−2 at 0.25 mA cm−2) and excellent cycle stability of 5000 cycles (0.0095% capacity decay per cycle). The assembled all‐flexible sodium‐ion battery delivers remarkable performance (high areal capacity of 1.42 mAh cm−2 at 0.3 mA cm−2 and superior energy density of 144 Wh kg−1), which are very close to the requirement of practical application. This work not only enlightens the material design and electrode engineering, but also provides a new kind of freestanding high energy density anode with great potential application prospective for SIBs.
Lithiophilic LiC6 Layers on Carbon Hosts Enabling Stable Li Metal Anode in Working Batteries
Authors: Shi Peng , Li Tao , Zhang Rui , Shen Xin , Cheng Xin‐Bing , Xu Rui , Huang Jia‐Qi , Chen Xiao‐Ru , Liu He , Zhang Qiang 
Published: January 2019

AbstractLithium (Li) metal‐based battery is among the most promising candidates for next‐generation rechargeable high‐energy‐density batteries. Carbon materials are strongly considered as the host of Li metal to relieve the powdery/dendritic Li formation and large volume change during repeated cycles. Herein, we describe the formation of a thin lithiophilic LiC6 layer between carbon fibers (CFs) and metallic Li in Li/CF composite anode obtained through a one‐step rolling method. An electron deviation from Li to carbon elevates the negativity of carbon atoms after Li intercalation as LiC6, which renders stronger binding between carbon framework and Li ions. The Li/CF | Li/CF batteries can operate for more than 90 h with a small polarization voltage of 120 mV at 50% discharge depth. The Li/CF | sulfur pouch cell exhibits a high discharge capacity of 3.25 mAh cm−2 and a large capacity retention rate of 98% after 100 cycles at 0.1 C. It is demonstrated that the as‐obtained Li/CF composite anode with lithiophilic LiC6 layers can effectively alleviate volume expansion and hinder dendritic and powdery morphology of Li deposits. This work sheds fresh light on the role of interfacial layers between host structure and Li metal in composite anode for long‐lifespan working batteries.
Probing the Domain Architecture in 2D α‐Mo2C via Polarized Raman Spectroscopy
Authors: Li Tianshu , Luo Weijun , Kitadai Hikari , Wang Xingzhi , Ling Xi 
Published: January 2019

AbstractMXenes are emerging 2D materials with intriguing properties such as excellent stability and high conductivity. Here, a systematic study on the Raman spectra of 2D α‐Mo2C (molybdenum carbide), a promising member in MXene family, is conducted. Six experimentally observed Raman modes from ultrathin α‐Mo2C crystal are first assigned with the assistance of phonon dispersion calculated from density functional theory. Angle‐resolved polarized Raman spectroscopy indicates the anisotropy of α‐Mo2C in the b–c plane. Raman spectroscopy is further used to study the unique domain structures of 2D α‐Mo2C crystals grown by chemical vapor deposition. A Raman mapping investigation suggests that most of the α‐Mo2C flakes contain multiple domains and the c‐axes of neighboring domains tend to form a 60° or 120° angle, due to the weak MoC bonds in this interstitial carbide and the low formation energy of the carbon chains along three equivalent directions. This study demonstrates that polarized Raman spectroscopy is a powerful and effective way to characterize the domain structures in α‐Mo2C, which will facilitate the further exploration of the domain‐structure‐related properties and potential applications of α‐Mo2C.
Loss is a loss, why categorize it? Mental accounting across cultures
Authors: Banerjee Pronobesh , Chatterjee Promothesh , Mishra Sanjay , Mishra Anubhav A. 
Published: January 2019

AbstractConsumers regularly track their expenses and assign them to categories like food, entertainment, and clothing, which is popularly known as mental accounting. In this paper, we show that consumption biases that result from mental accounting—underconsumption or overconsumption—are not prevalent in Easterners due to their holistic thinking style, whereas Westerners exhibit such biases due to their analytic thinking style. In Study 1, we collected data with Easterners (students from the eastern part of India) and show that they do not exhibit mental accounting biases as is seen in Westerners. In Study 2, we show that such differences in mental accounting across cultures result from their thinking styles by manipulating thinking styles within a Western population (American students from the Midwest). We also show that the differences in styles of thinking across cultures motivate two different types of accounting processes—a piecemeal accounting process in the Westerners and a comprehensive accounting process in the Easterners—which in turn influence the differences in mental accounting biases across cultures. This finding adds to the growing literature in cross‐cultural differences in consumer decision making and explores how and why a well‐documented robust effect, mental accounting, varies with the cultural background of the consumers.
Comparative Study of Alkali‐Cation‐Based (Li+, Na+, K+) Electrolytes in Acetonitrile and Alkylcarbonates
Authors: Amara Samia , Toulc'Hoat Joël , Timperman Laure , Biller Agnès , Galiano Hervé , Marcel Corinne , Ledigabel Matthieu , Anouti Mérièm 
Published: January 2019

AbstractThe development of a suitable functional electrolyte is urgently required for fast‐charging and high‐voltage alkali‐ion (Li, Na, K) batteries as well as next‐generation hybrids supercapacitors. Many recent works focused on an optimal selection of electrolytes for alkali‐ion based systems and their electrochemical performance but the understanding of the fundamental aspect that explains their different behaviour is rare. Herein, we report a comparative study of transport properties for LiPF6, NaPF6, KPF6 in acetonitrile (AN) and a binary mixture of ethylene carbonate (EC), dimethyl carbonate (DMC): (EC/DMC : 1/1, weigh) through conductivities, densities and viscosities measurements in wide temperature domain. By application of the Stokes‐Einstein, Nernst‐Einstein, and Jones Dole equations, the effective ionic solvated radius of cation (reff), the ionic dissociation coefficient (αD) and structuring Jones Dole's parameters (A, B) for salt are calculated and discussed according to solvent or cation nature as a function of temperature. From the results, we demonstrate that better mobility of potassium can be explained by the nature of the ion‐ion and ion‐solvent interactions due to its polarizability. In the same time, the predominance of triple ions in the case of K+, is a disadvantage at high concentration.
Corporate sustainability performance measurement based on a new multicriteria sorting method
Authors: Küçükbay Füsun , Sürücü Ebru 
Published: January 2019

AbstractThe concept of sustainability deals with protecting and sustaining society and environment for future generations while trying to meet the maximization of market capitalization objective. Despite the increased awareness of corporate sustainability, questions remain on how to measure performance. The objective of this paper is to propose a new measurement method, which is Multimoora Sort, for corporate sustainability performance and make an empirical case with the 25 companies listed in Fortune 500 USA. We chose four economic subcriteria, two environmental subcriteria, and four social subcriteria for the methodology. The results of the study show that the proposed methodology is a practical and efficient decision method. The most important contribution of the study to the literature is to present a new evaluation method in the measurement of sustainability performance as well as the results of the empirical case are supported by the resource dependency theory, institutional theory, and stakeholder theory.
Sustainable Asymmetric Organolithium Chemistry: Enantio‐ and Chemoselective Acylations through Recycling of Solvent, Sparteine, and Weinreb “Amine”
Authors: Monticelli Serena , Holzer Wolfgang , Langer Thierry , Roller Alexander , Olofsson Berit , Pace Vittorio 
Published: January 2019

AbstractThe well‐established Hoppe–Beak chemistry, which involves enantioselective generation of organolithium compounds in the presence of (−)‐sparteine, was revisited and applied to unprecedented acylations with Weinreb amides to access highly enantioenriched α‐oxyketones and cyclic α‐aminoketones. Recycling of the sustainable solvent cyclopentyl methyl ether, sparteine, and the released Weinreb “amine” [HNMe(OMe)] was possible through a simple work‐up procedure that enabled full recovery of these precious materials. The methodology features a robust scope and flexibility, thus allowing the enantioselective preparation of scaffolds amenable of further derivatization.
Establishing a balanced scorecard measurement system for integrated care organizations in China
Authors: Wu Xiaobo , Li Sihan , Xu Ning , Wu Dong , Zhang Xinli 
Published: January 2019

SummaryTo address, among other issues, the regional and international challenges of the heavy health care burden caused by an aging population, integrated care organizations (ICOs) were proposed at the end of the 20th century for health care delivery. However, the implementation of ICOs has not progressed smoothly, and the current results have not eliminated the imbalance of medical service capabilities among hospitals of different levels. To make up for the deficiency in the current evaluation system at ICOs and offer suggestions for improved sustainable health planning and management, this study establishes a balanced scorecard based on a comprehensive measurement system valid for a Chinese ICO by surveying the staff at the West China Hospital ICO. This study collected valid responses from 216 professional staff members at the ICO via questionnaires. K‐means clustering and the coefficient of variation method were used to evaluate the weights of the first‐ and second‐level indicators. The results show the importance ranking of the core perspectives of the ICO balanced scorecard in the following order: patient, internal process, learning and growth, and financial. The weight‐based analysis identified the importance ranking of all indicators and pointed to the areas that require close attention in future ICO planning and management.
Multiple shape memory behavior of highly oriented long‐chain‐branched poly(lactic acid) and its recovery mechanism
Authors: Li Jiafeng , Zhao Xiaowen , Ye Lin , Coates Phil , Caton‐Rose Fin 
Published: January 2019

AbstractThe shape memory effect of highly oriented long‐chain‐branched poly(lactic acid) (LCB‐PLA) prepared through solid‐phase die drawing technology was studied by comparison with PLA. When the recovery temperature increased from 60°C to 120°C, for PLA, only one‐step recovery at about 80°C can be observed and the recovery ratio was below 21.5%, while, for LCB‐PLA, multiple recovery behavior with high recovery ratio of 78.8% can be achieved. For oriented PLA, the recovery curve of the final sample showed the same trend with that of sample suffering just free drawing; while for oriented LCB‐PLA, the recovery curve of the final sample showed the same trend with that of sample suffering just die drawing. After shape recovery, the mechanical properties of LCB‐PLA showed a linear downward trend with the recovery temperature. Together with amorphous phase, the oriented mesomorphic phase, which formed during solid die drawing, can act as switching domains. And thus, upon heating, the chain segment of amorphous phase relaxed at first and triggered the first macroscopical shape recovery, leading to the decrease of long period (Lac) and the thickness of the amorphous layer (La). Then, with further increasing temperature, the oriented mesomorphic phase gradually relaxed resulting subsequently multi‐shape recovery, and the Lac and the La further decreased. Therefore, by regulating the recovery temperature of oriented LCB‐PLA, the shape recovery ratio and mechanical strength can be controlled effectively, and thus the self‐reinforced and self‐fastening effect can be achieved simultaneously for PLA as bone fixation material. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 872–883, 2019.
Polymer scaffold architecture is a key determinant in mast cell inflammatory and angiogenic responses
Authors: Abebayehu Daniel , Spence Andrew J. , McClure Michael J. , Haque Tamara T. , Rivera Kevin O. , Ryan John J. 
Published: January 2019

AbstractImplanted polymer scaffolds can induce inflammation leading to the foreign body response (FBR), fibrosis, and implant failure. Thus, it is important to understand how immune cells interact with scaffolds to mitigate inflammation and promote a regenerative response. We previously demonstrated that macrophage phenotype is modulated by fiber and pore diameters of an electrospun scaffold. However, it is unclear if this effect is consistent among other innate immune cells. Mast cells are inflammatory sentinels that play a vital role in the FBR of implanted biomaterials, as well as angiogenesis. We determined if altering electrospun scaffold architecture modulates mast cell responses, with the goal of promoting regenerative cell‐scaffold interactions. Polydioxanone (PDO) scaffolds were made from 60 mg/mL or 140 mg/mL PDO solutions, yielding structures with divergent fiber and pore diameters. Mouse mast cells plated on these scaffolds were activated with IL‐33 or lipopolysaccharide (LPS). Relative to the 60 mg/mL scaffold, 140 mg/mL scaffolds yielded less IL‐6 and TNF, and greater VEGF secretion. Pores >4–6 μm elicited less IL‐6 and TNF secretion. IL‐33‐induced VEGF regulation was more complex, showing effects of both pore size and fiber diameter. These data indicate parameters that can predict mast cell responses to scaffolds, informing biomaterial design to increase wound healing and diminish implant rejection. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 884–892, 2019.