bluuebunny/crossref_metadata_2025 huggingface dataset:
Multidimensional Synergistic Nanoarchitecture Exhibiting Highly Stable and Ultrafast Sodium‐Ion Storage
Authors: Tan Shuangshuang , Jiang Yalong , Wei Qiulong , Huang Qianming , Dai Yuhang , Xiong Fangyu , Li Qidong , An Qinyou , Xu Xu , Zhu Zizhong , Bai Xuedong , Mai Liqiang
Published: March 2018

Conversion‐type anodes with multielectron reactions are beneficial for achieving a high capacity in sodium‐ion batteries. Enhancing the electron/ion conductivity and structural stability are two key challenges in the development of high‐performance sodium storage. Herein, a novel multidimensionally assembled nanoarchitecture is presented, which consists of V2O3 nanoparticles embedded in amorphous carbon nanotubes that are then coassembled within a reduced graphene oxide (rGO) network, this materials is denoted V2O3⊂C‐NTs⊂rGO. The selective insertion and multiphase conversion mechanism of V2O3 in sodium‐ion storage is systematically demonstrated for the first time. Importantly, the naturally integrated advantages of each subunit synergistically provide a robust structure and rapid electron/ion transport, as confirmed by in situ and ex situ transmission electron microscopy experiments and kinetic analysis. Benefiting from the synergistic effects, the V2O3⊂C‐NTs⊂rGO anode delivers an ultralong cycle life (72.3% at 5 A g−1 after 15 000 cycles) and an ultrahigh rate capability (165 mAh g−1 at 20 A g−1, ≈30 s per charge/discharge). The synergistic design of the multidimensionally assembled nanoarchitecture produces superior advantages in energy storage.
3D‐Printing Electrolytes for Solid‐State Batteries
Authors: McOwen Dennis W. , Xu Shaomao , Gong Yunhui , Wen Yang , Godbey Griffin L. , Gritton Jack E. , Hamann Tanner R. , Dai Jiaqi , Hitz Gregory T. , Hu Liangbing , Wachsman Eric D.
Published: March 2018

Solid‐state batteries have many enticing advantages in terms of safety and stability, but the solid electrolytes upon which these batteries are based typically lead to high cell resistance. Both components of the resistance (interfacial, due to poor contact with electrolytes, and bulk, due to a thick electrolyte) are a result of the rudimentary manufacturing capabilities that exist for solid‐state electrolytes. In general, solid electrolytes are studied as flat pellets with planar interfaces, which minimizes interfacial contact area. Here, multiple ink formulations are developed that enable 3D printing of unique solid electrolyte microstructures with varying properties. These inks are used to 3D‐print a variety of patterns, which are then sintered to reveal thin, nonplanar, intricate architectures composed only of Li7La3Zr2O12 solid electrolyte. Using these 3D‐printing ink formulations to further study and optimize electrolyte structure could lead to solid‐state batteries with dramatically lower full cell resistance and higher energy and power density. In addition, the reported ink compositions could be used as a model recipe for other solid electrolyte or ceramic inks, perhaps enabling 3D printing in related fields.
In Situ Activation of 3D Porous Bi/Carbon Architectures: Toward High‐Energy and Stable Nickel–Bismuth Batteries
Authors: Zeng Yinxiang , Lin Ziqi , Wang Zifan , Wu Mingmei , Tong Yexiang , Lu Xihong
Published: March 2018

To achieve high‐energy and stable aqueous rechargeable batteries, state‐of‐the art of anode materials are needed. Bismuth (Bi) has recently emerged as an attractive anode material due to its highly reversible redox reaction and suitable negative operating working window. However, the capacity and durability of currently reported Bi anodes are still far from satisfactory. Here, an in situ activation strategy is reported to prepare a 3D porous high‐density Bi nanoparticles/carbon architecture (P–Bi–C) as an efficient anode for nickel–bismuth batteries. Taking advantages of the fast channels for charge transfer and ion diffusion, enhanced wettability, and accessible surface area, the highly loaded P–Bi–C electrode delivers a remarkable capacity of 2.11 mA h cm−2 as well as high rate capability (1.19 mA h cm−2 at 120 mA cm−2). To highlight, a robust aqueous rechargeable Ni//Bi battery based on the P–Bi–C anode is first constructed, achieving decent capacity (141 mA h g−1), impressive durability (94% capacity retention after 5000 cycles), and admirable energy density (16.9 mW h cm−3). This work paves the way for designing superfast nickel–bismuth batteries with high energy and long‐life and may inspire new development for aqueous rechargeable batteries.
Nonfullerene Tandem Organic Solar Cells with High Performance of 14.11%
Authors: Zhang Yamin , Kan Bin , Sun Yanna , Wang Yanbo , Xia Ruoxi , Ke Xin , Yi Yuan‐Qiu‐Qiang , Li Chenxi , Yip Hin‐Lap , Wan Xiangjian , Cao Yong , Chen Yongsheng
Published: March 2018

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.
Atomic Iridium Incorporated in Cobalt Hydroxide for Efficient Oxygen Evolution Catalysis in Neutral Electrolyte
Authors: Zhang Youkui , Wu Chuanqiang , Jiang Hongliang , Lin Yunxiang , Liu Hengjie , He Qun , Chen Shuangming , Duan Tao , Song Li
Published: March 2018

Developing highly efficient catalysts for oxygen evolution reaction (OER) in neutral media is extremely crucial for microbial electrolysis cells and electrochemical CO2 reduction. Herein, a facile one‐step approach is developed to synthesize a new type of well‐dispersed iridium (Ir) incorporated cobalt‐based hydroxide nanosheets (nominated as CoIr) for OER. The Ir species as clusters and single atoms are incorporated into the defect‐rich hydroxide nanosheets through the formation of rich Co–Ir species, as revealed by systematic synchrotron radiation based X‐ray spectroscopic characterizations combining with high‐angle annular dark‐field scanning transmission electron microscopy measurement. The optimized CoIr with 9.7 wt% Ir content displays highly efficient OER catalytic performance with an overpotential of 373 mV to achieve the current density of 10 mA cm−2 in 1.0 m phosphate buffer solution, significantly outperforming the commercial IrO2 catalysts. Further characterizations toward the catalyst after undergoing OER process indicate that unique Co oxyhydroxide and high valence Ir species with low‐coordination structure are formed due to the high oxidation potentials, which authentically contributes to superior OER performance. This work not only provides a state‐of‐the‐art OER catalyst in neutral media but also unravels the root of the excellent performance based on efficient structural identifications.
Charge‐Trapping‐Induced Non‐Ideal Behaviors in Organic Field‐Effect Transistors
Authors: Un Hio‐Ieng , Cheng Peng , Lei Ting , Yang Chi‐Yuan , Wang Jie‐Yu , Pei Jian
Published: March 2018

Organic field‐effect transistors (OFETs) with impressively high hole mobilities over 10 cm2 V−1 s−1 and electron mobilities over 1 cm2 V−1 s−1 have been reported in the past few years. However, significant non‐ideal electrical characteristics, e.g., voltage‐dependent mobilities, have been widely observed in both small‐molecule and polymer systems. This issue makes the accurate evaluation of the electrical performance impossible and also limits the practical applications of OFETs. Here, a semiconductor‐unrelated, charge‐trapping‐induced non‐ideality in OFETs is reported, and a revised model for the non‐ideal transfer characteristics is provided. The trapping process can be directly observed using scanning Kelvin probe microscopy. It is found that such trapping‐induced non‐ideality exists in OFETs with different types of charge carriers (p‐type or n‐type), different types of dielectric materials (inorganic and organic) that contain different functional groups (OH, NH2, COOH, etc.). As fas as it is known, this is the first report for the non‐ideal transport behaviors in OFETs caused by semiconductor‐independent charge trapping. This work reveals the significant role of dielectric charge trapping in the non‐ideal transistor characteristics and also provides guidelines for device engineering toward ideal OFETs.
A Review of Advanced Flexible Lithium‐Ion Batteries
Authors: Tao Tao , Lu Shengguo , Chen Ying
Published: March 2018

The rapid development of flexible electronics has triggered extensive efforts to explore matching flexible energy‐storage devices as power sources. Flexible lithium‐ion batteries (LIBs) have been demonstrated as the current most attractive and versatile energy storage devices for flexible electronics. A series of designs and constructions for flexible LIBs have been investigated in recent years. Particularly, significant progress has been achieved in finding high performance electrolyte and electrode materials, new structural designs, as well as suitable fabrication methods for flexible LIBs. In this review, the recent advances in the exploration of flexible lithium‐ion batteries are summarized and discussed, with special focus on the selectivity of flexible electrode/electrolyte materials, cell structure design, and full cell assembly process. Perspectives for the future development of flexible LIBs are also discussed.
Metallic 3D Random Nanocomposite Islands For Near‐Field Spatial Light Switching
Authors: Son Taehwang , Moon Gwiyeong , Lee Hongki , Kim Donghyun
Published: March 2018

Random nanocomposite islands have drawn significant interest for diverse applications due to extreme simplicity of fabricating nanoscale structures. In this paper, the near‐field characteristics of random nanoislands produced by spatial light switching are investigated, with light incidence switching among 14 incident channel modes. The results show that localized light fields are displaced from nanoislands almost linearly with the incident angle of channels. Also, light fields rotate in a manner aligned to the direction of light incidence. Ten‐channel spatial switching is found to provide coverage of near‐fields on the surface close to 90%. The numerical data are experimentally validated using fluorescent imaging and near‐field scanning optical microscopy. The results suggest the possibility of using random nanoislands for high performance imaging such as superresolution microscopy and molecular detection techniques.
Phonon‐Like Plasmonic Resonances in a Finite Number of Graphene Nanoribbons
Authors: Huang Lei , Liu Jianqiang , Deng Hongmei , Wu Shan
Published: March 2018

Graphene plasmon polaritons excited in individual and periodic nanoribbons microstructures have attracted enormous attention in plasmonics due to their complicated edge effect and excellent tunability. As the distance between neighboring graphene nanoribbons becomes small enough, the strong coupling between the plasmons in individual nanoribbons produces collective oscillations of surface plasmons in a graphene nanoribbons array, the dispersion of which behaves as phonons in a solid, that is, the phonon‐like plasmonic resonance mode. In this paper, such a phonon‐like plasmonic resonance is theoretically demonstrated in a finite number of graphene nanoribbons deposited on a silicon substrate. Based on the classical LC circuit model, an analytical dispersion relation is obtained to explain the simulated results. Furthermore, an electrically controlled plasmonic switch is proposed with a high performance based on the plasmonic phonon‐like resonance theory. The work provides the building blocks to construct graphene plasmonic circuits for future compact optoelectronic devices.
Liquid Crystals for Superior Electro‐Optic Performance Display Device with Power‐Saving Mode
Authors: Kim MinSu , Jin Heui Seok , Lee Seung Jae , Shin Yun‐Ho , Ham Hyeong Gyun , Yang Deng‐Ke , Bos Philip J. , Lee Joong Hee , Lee Seung Hee
Published: March 2018

An advantageous factor for the technology of displays is low power consumption. For power‐saving, low‐frequency driving of liquid crystal displays (LCDs) is useful. However, an unacceptable performance drop, from image‐flickering, occurs due to occurrence of the flexoelectric effect. Here, based on close agreement between experimental and simulated results, a new electro‐optic mode with optimization of both electrode structures and physical properties of the liquid crystal materials is demonstrated. Although the calculated electro‐optic properties are obtained for particular simulation conditions, the achieved transmittance is exceptional for LCDs using a power‐saving mode, and can result in complete elimination of static and dynamic flickering. It is believed the result will pave the way toward successful design for low‐power consumption and high‐performance LCDs.
Luminescent Diiridium Complexes with Bridging Pyrazolates: Characterization and Fabrication of OLEDs Using Vacuum Thermal Deposition
Authors: Liao Jia‐Ling , Rajakannu Palanisamy , Gnanasekaran Premkumar , Tsai Shang‐Ru , Lin Chun‐Han , Liu Shih‐Hung , Chang Chih‐Hao , Lee Gene‐Hsiang , Chou Pi‐Tai , Chen Zhong‐Ning , Chi Yun
Published: March 2018

A series of novel diiridium complexes (1–4) bearing both functional 2‐pyrazolyl‐6‐phenyl pyridine chelate and bidentate phenyl imidazolylidene chelate are synthesized, for which the pyrazolate fragment of the tridentate 2‐pyrazolyl‐6‐phenyl pyridine also behaves as the bridge to hold two iridium atoms in close vicinity. Their structure is unambiguously confirmed using X‐ray structure determination on the corresponding derivative 2a bearing 1,3‐bis(4‐fluorophenyl)‐1H‐Imidazolyl cyclometalate. Their photophysical and electrochemical properties are studied and further affirmed by the computational approaches. All these Ir(III) metal complexes 1–4 are very stable in both solution and solid film with near unity emission quantum efficiency. As opposed to most of diiridium complexes documented in literature, 1–4 are volatile and suitable for fabrication of organic light emitting diodes (OLEDs) under vacuum evaporation. The corresponding electroluminescent devices exhibit superior performance, among which external quantum efficiency of 27.6% using 2 as dopant stands for the record high of OLEDs using dinuclear Ir(III) complexes. They also offer a low roll‐off at high luminance, demonstrating their potential en route to high performance OLEDs.
Isothiocyanate Strategy for the Synthesis of Quaternary α‐Amino Acids Bearing a Spirocyclic Ring System
Authors: Frankowski Sebastian , Gajda Tadeusz , Albrecht Łukasz
Published: March 2018

This study demonstrates that isothiocyanates derived from α‐substituted α‐amino acids are useful building blocks in the heteroannulation reactions with electron‐deficient olefins. The developed strategy proceeds in a cascade manner and involves Michael addition followed by a cyclization via nucleophilic addition. Target, spirocyclic heterocycles bearing either a quaternary α‐amino acid moiety or α‐aminophosphonate group have been efficiently synthesized in very high yield (up to 99%) and with excellent stereocontrol. The usefulness of heterocycles obtained has been demonstrated in selected transformations.

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Enantioselective Synthesis of trans‐Vicinal Diamines via Rhodium‐Catalyzed [2+2] Cycloaddition of Allenamides
Authors: Zheng Wei‐Feng , Sun Gui‐Jun , Chen Liang , Kang Qiang
Published: March 2018

An efficient protocol for the enantioselective Rh‐catalyzed intermolecular head‐to‐head [2+2] cycloaddition of allenamides was developed. A variety of enantio‐enriched cyclobutane‐1,2‐diamine derivatives were achieved in good yields with good to excellent enantioselectivities.

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Lewis Acid‐Catalyzed Formal [3+3] Annulation of Propargylic Alcohols with 4‐Hydroxy‐2H‐chromen‐2‐ones
Authors: Han Ya‐Ping , Li Xue‐Song , Li Ming , Zhu Xin‐Yu , Liang Yong‐Min
Published: March 2018

A Lewis acid‐catalyzed formal [3+3] cascade annulation strategy for the formation of diverse tricyclic compounds possessing functionalized pyrano[3,2‐c]chromen‐5(2H)‐one fragments has been developed using propargylic alcohols and 4‐hydroxy‐2H‐chromen‐2‐ones as the substrates. The protocol provides a one‐step, environmentally benign method of accessing a broad range of pyrano[3,2‐c]chromen‐5(2H)‐one derivatives in excellent yields under mild conditions and with good functional‐group tolerance. The method is effective on the gram scale, which highlights the inherent practicality of this synthetic transformation.

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Application of 7‐Indolylmethanols in Catalytic Asymmetric Arylations with Tryptamines: Enantioselective Synthesis of 7‐indolylmethanes
Authors: Wang Hai‐Qing , Xu Meng‐Meng , Wan Ying , Mao Yu‐Jia , Mei Guang‐Jian , Shi Feng
Published: March 2018

The application of 7‐indolylmethanols in catalytic asymmetric reactions has been established via an enantioselective arylation reaction with tryptamines in the presence of chiral phosphoric acid, which afforded a series of structurally diversified chiral 7‐indolylmethanes in moderate to good yields and generally excellent enantioselectivities (23 examples, up to 92% ee). This reaction not only provides a useful strategy for the enantioselective synthesis of chiral 7‐indolylmethanes, but also represents a good example of 7‐indolylmethanol‐involved catalytic asymmetric reaction, which will greatly enrich the chemistry of indolylmethanols.

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Fe‐catalyzed dithiane radical induced C−S bond activation−addition to α, β‐unsaturated ketones
Authors: Min Deng , Yuan Xinyu , Liu Teng , Liu Jian , Tang Shouchu
Published: March 2018

An efficient and clean strategy to construct organosulfur compounds has been developed via a Fe‐catalyzed dithiane C−S bond activation/addition process with α, β‐unsaturated ketones. This C−S activation protocol exhibits excellent reactivities, and up to 92% yield of the corresponding thioether‐thioester derivatives could be obtained under the mild conditions, allowing the ready preparation of a number of synthetically valuable S‐linked conjugates.

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Highly Efficient Ammonia Synthesis Electrocatalyst: Single Ru Atom on Naturally Nanoporous Carbon Materials
Authors: Cao Yongyong , Gao Yijing , Zhou Hu , Chen Xianlang , Hu Hui , Deng Shengwei , Zhong Xing , Zhuang Guilin , Wang Jianguo
Published: March 2018

Stabilizing single‐atom metal catalysts with carbon materials and utilizing their synergistic effect remains challenging due to weak interactions between carbon‐based supports and metals. Density functional theory (DFT) calculations indicate that a single Ru atom was supported on a wide range of natural nanoporous carbon materials, including C2N, triazine‐C3N4 (T‐C3N4), and γ‐graphene. These carbon materials belong to a new generation of highly efficient electrocatalysts for the N2 reduction reaction (NRR) and are named Ru1@C2N, Ru1@T‐C3N4, and Ru1@γ‐graphyne, respectively. Ab initio molecular dynamic (AIMD) simulations show that a single Ru atom can be stably anchored in the nanopores of these carbon materials with strong cohesive energy. Compared with parallel adsorption configuration, the vertical adsorption configuration of N2 exhibits higher adsorption energy. The calculated Gibbs free energy reveals N2 reduction on the three catalysts via associative mechanisms. Despite the similar limiting potentials (−0.96, −0.94, and −0.98 V on Ru1@C2N, Ru1@T‐C3N4, and Ru1@γ‐graphynes, respectively), the limiting step differs, indicating the significant effects of carbon material substrates on electrochemical NRR. However, the competitive and efficient hydrogen evolution reaction (HER) changes the potential determining step and increases the overpotential for the electrochemical nitrogen reduction (NRR). This study provides insights for experimental synthesis of electrocatalysts for N2 reduction.
Antimicrobial activity of organic–inorganic hybrid films based on gelatin and organomodified silicones
Authors: Wojciechowska Patrycja , Tichoniuk Mariusz , Gwiazdowska Daniela , Maciejewski Hieronim , Nowicki Marek
Published: March 2018

Gelatin–siloxane hybrid films containing antimicrobial agents were prepared in the two‐step procedure. First, gelatin was chemically modified with organomodified silicones containing epoxy (S1) and both epoxy and fluoroalkyl groups (S2). Next, antimicrobial agents such as lysozyme, EDTA, and nisin, in various concentrations, were introduced into obtained hybrid solution, prior to solvent casting of the films. Antimicrobial activity of prepared samples, as well as neat gelatin and gelatin–siloxane hybrid as a reference, was investigated using a modified agar diffusion method against several bacterial strains (Aeromonas hydrophila, Bacillus subtilis, Escherichia coli) and opportunistic fungus (yeast species Candida albicans). Prepared gelatin–siloxane films were characterized using FT‐IR, thermal and SEM analysis. Mechanical properties and swelling behavior of the samples were also investigated. The influence of type and amount of organosilicon compound used for modification of gelatin, as well as type and concentration of applied active agent on antimicrobial activity, was determined. We observed higher antimicrobial activity for all synthesized gelatin–siloxane hybrids than for unmodified gelatin with lysozyme, nisin, and EDTA prepared as comparison. Moreover, samples obtained with siloxane containing fluoroalkyl groups (S2) showed higher resistance to microbial agents than hybrids with S1 siloxane. Hybrid films showed also better water stability than neat biopolymer.
Fever‐Inspired Immunotherapy Based on Photothermal CpG Nanotherapeutics: The Critical Role of Mild Heat in Regulating Tumor Microenvironment
Authors: Li Yan , He Lianghua , Dong Haiqing , Liu Yiqiong , Wang Kun , Li Ang , Ren Tianbin , Shi Donglu , Li Yongyong
Published: March 2018

Although there have been more than 100 clinical trials, CpG‐based immunotherapy has been seriously hindered by complications in the immunosuppressive microenvironment of established tumors. Inspired by the decisive role of fever upon systemic immunity, a photothermal CpG nanotherapeutics (PCN) method with the capability to induce an immunofavorable tumor microenvironment by casting a fever‐relevant heat (43 °C) in the tumor region is developed. High‐throughput gene profile analysis identifies nine differentially expressed genes that are closely immune‐related upon mild heat, accompanied by IL‐6 upregulation, a pyrogenic cytokine usually found during fever. When treated with intratumor PCN injection enabling mild heating in the tumor region, the 4T1 tumor‐bearing mice exhibit significantly improved antitumor immune effects compared with the control group. Superb efficacy is evident from pronounced apoptotic cell death, activated innate immune cells, enhanced tumor perfusion, and intensified innate and adaptive immune responses. This work highlights the crucial role of mild heat in modulating the microenvironment in optimum for improved immunotherapy, by converting the tumor into an in situ vaccine.
Multidimensional Evolution of Carbon Structures Underpinned by Temperature‐Induced Intermediate of Chloride for Sodium‐Ion Batteries
Authors: Ge Peng , Hou Hongshuai , Cao Xiaoyu , Li Sijie , Zhao Ganggang , Guo Tianxiao , Wang Chao , Ji Xiaobo
Published: March 2018

Different dimensions of carbon materials with various features have captured numerous interests due to their applications on the tremendous fields. Restricted by the raw materials and devices, the controlling of their morphology is a major challenge. Utilizing the catalytic features of the intermediates from the low‐cost salts and polymerization of 0D carbon quantum dots (CQDs), 0D CQDs are expected to self‐assemble into 1/2/3D carbon structures with the assistance of temperature‐induced intermediates (e.g., ZnO, Ni, and Cu) from the salts (ZnCl2, NiCl2, and CuCl). The formation mechanisms are illustrated as follows: 1) the “orient induction” to evoke “vine style” growth mechanism of ZnO; 2) the “dissolution–precipitation” of Ni; and 3) the “surface adsorption self‐limited” of Cu. Subsequently, the degree of graphitization, interlayer distance, and special surface area are investigated in detail. 1D structure from 700 °C as anode displays a high Na‐storage capacity of 301.2 mAh g−1 at 0.1 A g−1 after 200 cycles and 107 mAh g−1 at 5.0 A g−1 after 5000 cycles. Quantitative kinetics analysis confirms the fundamentals of the enhanced rate capacity and the potential region of Na‐insertion/extraction. This elaborate work opens up an avenue toward the design of carbon with multidimensions and in‐depth understanding of their sodium‐storage features.
High Electromagnetic Waves Absorbing Performance of a Multilayer‐Like Structure Absorber Containing Activated Carbon Hollow Porous Fibers–Carbon Nanotubes and Fe3O4Nanoparticles
Authors: Gao Xuehua , Wu Xiangyi , Qiu Jun
Published: March 2018

Carbon nanotubes (CNTs) are grown on the surface of activated carbon hollow porous fibers (ACHFs) by chemical vapor deposition. A multilayer‐like structure absorber ACHFs–CNTs–Fe3O4is prepared when Fe3O4nanoparticles/epoxy resin are injected into the hollow structure of ACHFs. Microwave reflection loss, permittivity, and permeability of ACHFs–CNTs–Fe3O4in 2–18 GHz are measured. The results show that the minimum reflection loss of ACHFs–CNTs–Fe3O4has reached to −46.828 dB at 14.4 GHz with the thickness of 2.5 mm, and the bandwidth below −10 dB can be as broad as 7.2 GHz. A wide effective absorbing bandwidth can be 13.54 GHz with the variation of the sample thickness from 1.5 to 5.0 mm. The low minimum reflection loss may result from electromagnetic coupling effect of ACHFs, CNTs, and Fe3O4nanomagnetic particles. The broad absorbing bandwidth is ascribed to its special multilayer‐like structure.
Outstanding Comprehensive Performance of La(Fe, Si)13Hy/In Composite with Durable Service Life for Magnetic Refrigeration
Authors: Wang YiXu , Zhang Hu , Liu EnKe , Zhong XiChun , Tao Kun , Wu MeiLing , Xing ChengFen , Xiao YaNing , Liu Jian , Long Yi
Published: March 2018

Magnetic refrigeration based on magnetocaloric effect (MCE) has become a promisingly alternative technology to the conventional vapor‐compression refrigeration. A great number of magnetic materials have been reported to exhibit larger MCE than that of the benchmark magnetic refrigerant Gd. However, these materials still have severe shortcomings on the “Non‐MCE” properties, such as hard preparation and fabrication, low thermal conductivity λ, and poor corrosion resistance and cycling stabilities, which hinder the practical application of these materials. In this paper, a novel La(Fe, Si)13Hy/In composite which is prepared by a readily available hot pressing method is demonstrated to exhibit an outstanding comprehensive performance with durable service life in various aspects. Noteworthily, the ΔSM does not decrease but increases with increasing nonmagnetic In metal. This advantageous anomaly is related to the strengthening of the first‐order itinerant electron metamagnetic transition induced by residual compression stress and surrounded constraints in the composite. The present results make La(Fe, Si)13Hy/In composite the most attractive alternative to Gd for magnetic refrigeration. Moreover, this work also provides a feasible way to solve the serious issues toward applications for La(Fe, Si)13‐based materials and other brittle magnetocaloric materials.
Mixed Domains Enhance Charge Generation and Extraction in Bulk‐Heterojunction Solar Cells with Small‐Molecule Donors
Authors: Alqahtani Obaid , Babics Maxime , Gorenflot Julien , Savikhin Victoria , Ferron Thomas , Balawi Ahmed H. , Paulke Andreas , Kan Zhipeng , Pope Michael , Clulow Andrew J. , Wolf Jannic , Burn Paul L. , Gentle Ian R. , Neher Dieter , Toney Michael F. , Laquai Frédéric , Beaujuge Pierre M. , Collins Brian A.
Published: March 2018

The interplay between nanomorphology and efficiency of polymer‐fullerene bulk‐heterojunction (BHJ) solar cells has been the subject of intense research, but the generality of these concepts for small‐molecule (SM) BHJs remains unclear. Here, the relation between performance; charge generation, recombination, and extraction dynamics; and nanomorphology achievable with two SM donors benzo[1,2‐b:4,5‐b]dithiophene‐pyrido[3,4‐b]‐pyrazine BDT(PPTh2)2, namely SM1 and SM2, differing by their side‐chains, are examined as a function of solution additive composition. The results show that the additive 1,8‐diiodooctane acts as a plasticizer in the blends, increases domain size, and promotes ordering/crystallinity. Surprisingly, the system with high domain purity (SM1) exhibits both poor exciton harvesting and severe charge trapping, alleviated only slightly with increased crystallinity. In contrast, the system consisting of mixed domains and lower crystallinity (SM2) shows both excellent exciton harvesting and low charge recombination losses. Importantly, the onset of large, pure crystallites in the latter (SM2) system reduces efficiency, pointing to possible differences in the ideal morphologies for SM‐based BHJ solar cells compared with polymer‐fullerene devices. In polymer‐based systems, tie chains between pure polymer crystals establish a continuous charge transport network, whereas SM‐based active layers may in some cases require mixed domains that enable both aggregation and charge percolation to the electrodes.
Boron Element Nanowires Electrode for Supercapacitors
Authors: Xue Qi , Gan Haibo , Huang Yan , Zhu Minshen , Pei Zengxia , Li Hongfei , Deng Shaozhi , Liu Fei , Zhi Chunyi
Published: March 2018

The pursuit of new categories of active materials as electrodes of supercapacitors remains a great challenge. Herein, for the first time, elemental boron as a superior electrode material of supercapacitors is reported, which exhibits significantly high capacitances and excellent rate performance in all alkaline, neutral, and acidic electrolytes. Notably, boron nanowire‐carbon fiber cloth (BNWs‐CFC) electrodes achieve a capacitance up to 42.8 mF cm−2 at a scan rate of 5 mV s−1 and 60.2 mF cm−2 at a current density of 0.2 mA cm−2 in the acidic electrolyte. Moreover, in all these three kinds of electrolytes, BNWs‐CFC electrodes demonstrate a decent cycling stability with >80% capacitance retention after 8000 charging/discharging cycles. The Dominating energy storage mechanism of BNWs in the different electrolytes is analyzed by looking into the kinetics of the electrochemical process. Subsequently, the BNWs‐CFC electrode is used to fabricate a flexible solid‐state supercapacitor, which reveals a specific capacitance up to 22.73 mF cm−2 and good mechanical performance after 1000 bending cycles. This study opens a new avenue to explore elemental boron‐based new nanomaterials for the application of energy storage with superior electrochemical performance.
Low‐Defect and Low‐Porosity Hard Carbon with High Coulombic Efficiency and High Capacity for Practical Sodium Ion Battery Anode
Authors: Xiao Lifen , Lu Haiyan , Fang Yongjin , Sushko Maria L. , Cao Yuliang , Ai Xinping , Yang Hanxi , Liu Jun
Published: March 2018

Hard carbon is regarded as the most promising anode material for commercialization of Na ion batteries because of its high capacity and low cost. At present, the practical utilization of hard carbon anodes is largely limited by the low initial Coulombic efficiency (ICE). Na ions have been found to adopt an adsorption–insertion storage mechanism. In this paper a systematic way to control the defect concentration and porosity of hard carbon with similar overall architectures is shown. This study elucidates that the defects in the graphite layers are directly related to the ICE as they would trap Na ions and create a repulsive electric field for other Na ions so as to shorten the low‐voltage intercalation capacity. The obtained low defect and porosity hard carbon electrode has achieved the highest ICE of 86.1% (94.5% for pure hard carbon material by subtracting that of the conductive carbon black), reversible capacity of 361 mA h g−1, and excellent cycle stability (93.4% of capacity retention over 100 cycles). This result sheds light on feasible design principles for high performance Na storage hard carbon: suitable carbon layer distance and defect free graphitic layers.
Recent Development of Metallic (1T) Phase of Molybdenum Disulfide for Energy Conversion and Storage
Authors: Lei Zhendong , Zhan Jing , Tang Liang , Zhang Yong , Wang Yong
Published: March 2018

The development of a feasible and inexpensive strategy to obtain and utilize sustainable energy is an important issue for the sustainable development of human society. Over the past decade, significant progress has been made in the development of novel functional materials for energy conversion and storage. Owing to their unique physico‐chemical properties, 2D layered materials, such as graphene and transition metal dichalcogenides, have attracted great interest in energy‐related research. 1T‐MoS2 is a metallic phase of molybdenum disulfide (MoS2) with extraordinary electronic conductivity, enlarged interlayer spacing, and more electrochemically active sites along the basal plane, which offers intriguing benefits for energy‐related applications compared to its semiconducting counterpart (2H‐MoS2). This review summarizes the preparation and structure–property relationships of 1T‐MoS2, as well as the underlying relations between the metallic (1T) and semiconducting (2H) phases of MoS2. Recent progress in the preparation and stabilization of 1T‐MoS2 materials and their applications for energy conversion and storage are discussed, including water splitting to form hydrogen via photo/electrocatalysis and electricity storage in lithium‐ion batteries, sodium‐ion batteries, magnesium‐ion batteries, and supercapacitors. Optimization strategies of 1T‐MoS2 to obtain enhanced practical properties based on theoretical calculations are also presented.
Electrochemical CO2 Reduction with Atomic Iron‐Dispersed on Nitrogen‐Doped Graphene
Authors: Zhang Chenhao , Yang Shize , Wu Jingjie , Liu Mingjie , Yazdi Sadegh , Ren Muqing , Sha Junwei , Zhong Jun , Nie Kaiqi , Jalilov Almaz S. , Li Zhenyuan , Li Huaming , Yakobson Boris I. , Wu Qin , Ringe Emilie , Xu Hui , Ajayan Pulickel M. , Tour James M.
Published: March 2018

Electrochemical reduction of CO2 provides an opportunity to reach a carbon‐neutral energy recycling regime, in which CO2 emissions from fuel use are collected and converted back to fuels. The reduction of CO2 to CO is the first step toward the synthesis of more complex carbon‐based fuels and chemicals. Therefore, understanding this step is crucial for the development of high‐performance electrocatalyst for CO2 conversion to higher order products such as hydrocarbons. Here, atomic iron dispersed on nitrogen‐doped graphene (Fe/NG) is synthesized as an efficient electrocatalyst for CO2 reduction to CO. Fe/NG has a low reduction overpotential with high Faradic efficiency up to 80%. The existence of nitrogen‐confined atomic Fe moieties on the nitrogen‐doped graphene layer is confirmed by aberration‐corrected high‐angle annular dark‐field scanning transmission electron microscopy and X‐ray absorption fine structure analysis. The Fe/NG catalysts provide an ideal platform for comparative studies of the effect of the catalytic center on the electrocatalytic performance. The CO2 reduction reaction mechanism on atomic Fe surrounded by four N atoms (Fe–N4) embedded in nitrogen‐doped graphene is further investigated through density functional theory calculations, revealing a possible promotional effect of nitrogen doping on graphene.
A Monodisperse Rh2P‐Based Electrocatalyst for Highly Efficient and pH‐Universal Hydrogen Evolution Reaction
Authors: Yang Fulin , Zhao Yuanmeng , Du Yeshuang , Chen Yongting , Cheng Gongzhen , Chen Shengli , Luo Wei
Published: March 2018

The search for Pt‐free electrocatalysts exceeding pH‐universal hydrogen evolution reaction (HER) activities when compared to the state‐of‐the‐art commercial Pt/C is highly desirable for the development of renewable energy conversion systems but still remains a huge challenge. Here a colloidal synthesis of monodisperse Rh2P nanoparticles with an average size of 2.8 nm and their superior catalytic activities for pH‐universal HER are reported. Significantly, the Rh2P catalyst displays remarkable HER performance with overpotentials of 14, 30, and 38 mV to achieve 10 mA cm−2 in 0.5 m H2SO4, 1.0 m KOH, and 1.0 m phosphate‐buffered saline, respectively, exceeding almost all the documented electrocatalysts, including the commercial 20 wt% Pt/C. Density functional theory calculations reveal that the introduction of P into Rh can weaken the H adsorption strength of Rh2P to nearly zero, beneficial for boosting HER performance.
Carrier Interfacial Engineering by Bismuth Modification for Efficient and Thermoresistant Perovskite Solar Cells
Authors: Chen Cong , Liu Dali , Zhang Boxue , Bi Wenbo , Li Hao , Jin Junjie , Chen Xu , Xu Lin , Song Hongwei , Dai Qilin
Published: March 2018

Organic–inorganic halide perovskite solar cells (PSCs) have emerged as attractive alternatives to conventional solar cells. It is still a challenge to obtain PSCs with good thermal stability and high permanence, especially at extreme outdoor temperatures. This work systematically studies the effects of Bi3+ modification on structural, electrical, and optical properties of perovskite films (FA0.83MA0.17Pb(I0.83Br0.17)3) and the performance of corresponding PSCs. The results indicate that Bi3+ modified PSCs can achieve better thermal stability, photovoltaic response, and reproducibility compared with control cells due to the decreased grain boundaries, enhanced crystallization, and improved electron extraction from perovskite film. As a result, the modified PSC exhibits an optimized power conversion efficiency (PCE) of 19.4% compared with 18.3% for the optimized control device, accompanied by better thermoresistant ability under 100–180 °C and enhanced long‐term stability. The degradation rate of the modified device is reduced by an order of magnitude due to effective structural defect modification in perovskite photoactive layer. It could maintain more than two months at 60 °C. These results shed light on the origin of crystallization and thermal stability of perovskite films, and provide an approach to solve thermal stability issue of PSCs.
Crystal Structure Induced Ultralow Lattice Thermal Conductivity in Thermoelectric Ag9AlSe6
Authors: Li Wen , Lin Siqi , Weiss Manuel , Chen Zhiwei , Li Juan , Xu Yidong , Zeier Wolfgang G. , Pei Yanzhong
Published: March 2018

Recent discoveries of novel thermoelectric materials largely rely on an intrinsic low lattice thermal conductivity. This results from various mechanisms including low sound velocity, complex crystal structure, liquid‐like ions, and lattice anharmonicity. Here semiconducting Ag9AlSe6 with many weakly bonded and highly disordered cations is shown to be a promising novel thermoelectric material, due to its ultralow lattice thermal conductivity (κL) of ≈0.3 W m−1 K−1 in the entire temperature range. Such a low κL is believed to be a result of its (1) complex crystal structure for a small population of acoustic phonons, (2) soft bonding for an overall low sound velocity (1300 m s−1), and (3) massive disordering of Ag ions. Its electronic transport properties can be well understood by a single parabolic band model with acoustic scattering. The achieved thermoelectric figure of merit (zT) can be as high as unity, which is unlike conventional thermoelectric materials, which rely heavily on a high power factor. This work not only demonstrates Ag9AlSe6 as a promising thermoelectric material, but also paves the way for the exploration of novel thermoelectrics with a complex crystal structure with weakly bonded and highly disordered constituent elements in the structure.
MOF‐Based Transparent Passivation Layer Modified ZnO Nanorod Arrays for Enhanced Photo‐Electrochemical Water Splitting
Authors: Li Xiao , Liu Shengwei , Fan Ke , Liu Zhaoqing , Song Bo , Yu Jiaguo
Published: March 2018

This study introduces zeolitic imidazolate framework‐8 (ZIF‐8) as the first metal‐organic framework based transparent surface passivation layer for photo‐electrochemical (PEC) water splitting. A significant enhancement for PEC water oxidation is demonstrated based on the in situ seamless coating of ZIF‐8 surface passivation layer on Ni foam (NF) supported ZnO nanorod arrays photoanode. The PEC performance is improved by optimizing the ZIF‐8 thickness and by grafting Ni(OH)2 nanosheets as synergetic co‐catalyst. With respect to ZnO/NF, the optimized Ni(OH)2/ZIF‐8/ZnO/NF photoanode exhibits a two times larger photocurrent density of 1.95 mA cm−2 and also a two times larger incident photon to current conversion efficiency of 40.05% (350 nm) at 1.23 V versus RHE (VRHE) under AM 1.5 G. The synergetic surface passivation and the co‐catalyst modification contribute to prolonging the charge lifetime, to promoting the charge transfer, and to decreasing the overpotential for water oxidation.
H2V3O8 Nanowire/Graphene Electrodes for Aqueous Rechargeable Zinc Ion Batteries with High Rate Capability and Large Capacity
Authors: Pang Qiang , Sun Congli , Yu Yanhao , Zhao Kangning , Zhang Ziyi , Voyles Paul M. , Chen Gang , Wei Yingjin , Wang Xudong
Published: March 2018

Aqueous rechargeable zinc ion batteries are considered a promising candidate for large‐scale energy storage owing to their low cost and high safety nature. A composite material comprised of H2V3O8 nanowires (NWs) wrapped by graphene sheets and used as the cathode material for aqueous rechargeable zinc ion batteries is developed. Owing to the synergistic merits of desirable structural features of H2V3O8 NWs and high conductivity of the graphene network, the H2V3O8 NW/graphene composite exhibits superior zinc ion storage performance including high capacity of 394 mA h g−1 at 1/3 C, high rate capability of 270 mA h g−1 at 20 C and excellent cycling stability of up to 2000 cycles with a capacity retention of 87%. The battery offers a high energy density of 168 W h kg−1 at 1/3 C and a high power density of 2215 W kg−1 at 20 C (calculated based on the total weight of H2V3O8 NW/graphene composite and the theoretically required amount of Zn). Systematic structural and elemental characterization confirm the reversible Zn2+ and water cointercalation electrochemical reaction mechanism. This work brings a new prospect of designing high‐performance aqueous rechargeable zinc ion batteries for grid‐scale energy storage.
Editorial Processes in Free Open Access Medical Educational (FOAM) Resources
Authors: Azim Arden , Beck‐Esmay Jennifer , Chan Teresa M.
Published: March 2018

Background

Much of the skepticism toward online educational resources (OERs) in emergency medicine (EM) stems from the low barrier to publishing and a perceived lack of editorial rigor. Learners and educators have demonstrated unreliable gestalt ratings of OERs, suggesting a lack of capacity to consistently appraise these resources. The development of tools to guide clinicians and learners in the selection and use of blogs and podcasts is a growing area of interest. Disclosure of editorial process was identified in previous studies as an important quality indicator for OERs. However, little is known about editorial process in online EM resources and whether it can be reliably integrated into a critical appraisal tool.

Methods

Two reviewers assessed 100 top EM and critical care OERs for mention and description of editorial process and academic and nonacademic affiliations. Ninety‐two sites were accessible for review. All sites were also contacted to attempt clarification of their editorial process. Inter‐rater reliability for mention and description of editorial process was evaluated using Cohen's kappa, and the relationship between academic affiliation and disclosure of editorial process was assessed by odds ratio (OR).

Results

Eleven sites mentioned an editorial process, and 10 of these sites included a description. Five of the seven sites that responded to contact also described an editorial process. Inter‐rater agreement was excellent for mention (κ = 0.90) and description (κ = 1.00) of editorial process. Eighteen sites listed academic affiliations and 21 sites had nonacademic affiliations. A greater proportion of sites with academic affiliations disclosed their editorial process compared to sites without academic affiliations (OR = 5.3, 95% confidence interval [CI] = 1.3–21.0; difference in proportions of 0.40, 95% CI = 11.6–60.8).

Conclusions

Although transparency is lacking, editorial processes exist among OERs. Inter‐rater reliability for disclosure of editorial process is excellent, supporting its use within critical appraisal tools.
Clinical impact of developing better practices at the institutional level on surgical outcomes after distal pancreatectomy in 1515 patients: Domestic audit of the Japanese Society of Pancreatic Surgery
Authors: Satoi Sohei , Yamamoto Tomohisa , Motoi Fuyuhiko , Matsumoto Ippei , Yoshitomi Hideyuki , Amano Ryosuke , Tahara Munenori , Murakami Yoshiaki , Arimitsu Hidehito , Hirono Seiko , Sho Masayuki , Ryota Hironori , Ohtsuka Masayuki , Unno Michiaki , Takeyama Yoshifumi , Yamaue Hiroki
Published: March 2018

Background and Aim

Institutional standardization in the perioperative management of distal pancreatectomy (DP) has not been evaluated in a multicenter setting. The aim of the present study was to assess the influence of institutional standardization on the development of postoperative complications after DP.

Methods

Data were collected from 1515 patients who underwent DP in 2006, 2010, and 2014 at 53 institutions in Japan. A standardized institution (SI) was defined as one that implemented ≥6 of 11 quality initiatives according to departmental policy. There were 541 patients in the SI group and 974 in the non‐SI group. Clinical parameters were compared between groups. Risk factors for morbidity and mortality were assessed by logistic regression analysis with a mixed‐effects model.

Results

Proportion of patients who underwent DP in SI increased from 16.5% in 2006 to 46.4% in 2014. The SI group experienced an improved process of care and a lower frequency of severe complications vs the non‐SI group (grade III/IV Clavien‐Dindo; 22% vs 29%, respectively, clinically relevant postoperative pancreatic fistula; 22% vs 31%, respectively, P < .05 for both). Duration of in‐hospital stay in the SI group was significantly shorter than that in the non‐SI group (16 [5‐183] vs 20 postoperative days [5‐204], respectively; P = .002). Multivariate analysis with a mixed‐effects model showed that soft pancreas, late drain removal, excess blood loss and long surgical time were risk factors for post‐DP complications (P < .05). Pancreatic texture, drain management and surgical factors, but not standardization of care, were associated with a lower incidence of post‐DP complications.