bluuebunny/crossref_metadata_2025_split huggingface dataset:
In Situ Observation of Point‐Defect‐Induced Unit‐Cell‐Wise Energy Storage Pathway in Antiferroelectric PbZrO3
Authors: Wei Xian‐Kui , Jia Chun‐Lin , Roleder Krystian , Dunin‐Borkowski Rafal E. , Mayer Joachim 
Published: January 2021

AbstractPhase transition is established to govern electrostatic energy storage for antiferroelectric (AFE)‐type dielectric capacitors. However, the source of inducing the phase transition and the pathway of storing the energy remains elusive so far given the ultrafast charging/discharging process under normal working conditions. Here, by slowing down the phase‐transition speed using electron‐beam irradiation as an external stimulus, the in situ dynamic energy‐storage process in AFE PbZrO3 is captured by using atomic‐resolution transmission electron microscopy. Specifically, it is found that oxygen‐lead‐vacancy‐induced defect core acts as a seed to initiate the antiferrodistortive‐to‐ferrodistortive transition in antiparallel‐Pb‐based structural frames. Associated with polarity evolution of the compressively strained defect core, the ferroelectric (FE)–ferrodistortive state expands bilaterally along the b‐axis direction and then develops into charged domain configurations during the energy‐storage process, which is further evidenced by observations at the ordinary FE states. With filling the gap of perception, the findings here provide a straightforward approach of unveiling the unit‐cell‐wise energy storage pathway in chemical defect‐engineered dielectric ceramics.
Ultraflexible and Malleable Fe/BaTiO3 Multiferroic Heterostructures for Functional Devices
Authors: Zhao Yanan , Peng Renci , Guo Yunting , Liu Zhijie , Dong Yongqi , Zhao Shishun , Li Yaojin , Dong Guohua , Hu Yue , Zhang Junwei , Peng Yong , Yang Tiannan , Tian Bian , Zhao Yifan , Zhou Ziyao , Jiang Zhuangde , Luo Zhenlin , Liu Ming 
Published: January 2021

AbstractThe high demand for flexible spintronics based on multiferroic heterostructures makes growing high‐quality flexible, functional oxides urgently, in which needs to be deposited on lattice‐matched substrates. In this paper, ultraflexible and malleable iron (Fe)/BaTiO3 (BTO) multiferroic heterostructures are demonstrated, showing a perfect crystallinity and hetero‐epitaxial growth. In terms of performance, they indicate good multiferroic properties and excellent bending tunability, as well as obvious magnetoelectric (ME) coupling effect. During the phase transformation from the rhombohedral phase to the orthorhombic phase of BTO layers in the heating process, a large ME coupling coefficient of 120 Oe °C−1 along the out‐of‐plane direction is obtained. This value keeps consistent in the phase‐field simulation of magnetic domain evolution, in which the biaxial compressive strain induced‐magnetoelastic anisotropy facilitates the magnetic easy axis of Fe layers to the [110] or [–1–10] direction. Besides, ultraflexible Fe/BTO heterostructures are found to have a 690 Oe ferromagnetic resonance (FMR) field shift along the out‐of‐plane direction under the flexible tuning (R = 5 mm). This work should pave a way toward flexible spintronic and functional devices with fast speed, portability, and low energy consumption.
Defective Graphitic Carbon Nitride Modified Separators with Efficient Polysulfide Traps and Catalytic Sites for Fast and Reliable Sulfur Electrochemistry
Authors: Tong Zhaoming , Huang Liang , Liu Haipeng , Lei Wen , Zhang Haijun , Zhang Shaowei , Jia Quanli 
Published: January 2021

AbstractThe serious shuttle effect of lithium‐sulfur batteries limits the efficient realization of high rate charging and discharging under high sulfur loading in practical applications. Herein, this work reports a strong mitigation toward lithium polysulfide (LiPSs) adsorption/catalysis by introducing defective graphite phase carbon nitride (g‐C3N4) as an effective additive. Without significant weight increase, the nitrogen deficient g‐C3N4, in the form of ultrafine spindle‐like nitrogen deficient g‐C3N4−x (sCN), can be easily combined with commercial poly‐propylene (PP) separators after hydrophilic modification of polydopamine, which corresponds to an ultralow overall weightiness contribution of 0.17 mg cm−2. Physical/electrochemical characterizations and theoretical studies reveal that sCN exhibits strong electrostatic attraction with LiPSs by nitrogen defects and new formation of cyano groups near edges, thereby maintaining rapid and reliable LiS electrochemistry. Of particular importance is the chainmail catalyst design with separators that enable magic polysulfides adsorption effect and desirable thermostability/wettability, which guarantees the sCNPP‐assembled cells with long and stable durability over 500 cycles at 5.0 C (capacity fading rate: 0.05% per cycle), and a high capability of 476 mAh g−1 is obtained.
Effects of Mesenchymal Stem Cell‐Derived Paracrine Signals and Their Delivery Strategies
Authors: Chang Calvin , Yan Jerry , Yao Zhicheng , Zhang Chi , Li Xiaowei , Mao Hai‐Quan 
Published: January 2021

AbstractMesenchymal stem cells (MSCs) have been widely studied as a versatile cell source for tissue regeneration and remodeling due to their potent bioactivity, which includes modulation of inflammation response, macrophage polarization toward proregenerative lineage, promotion of angiogenesis, and reduction in fibrosis. This review focuses on profiling the effects of paracrine signals of MSCs, commonly referred to as the secretome, and highlighting the various engineering approaches to tune the MSC secretome. Recent advances in biomaterials‐based therapeutic strategies for delivery of MSCs and MSC‐derived secretome in the form of extracellular vesicles are discussed, along with their advantages and challenges.
3D‐Printable Fluoropolymer Gas Diffusion Layers for CO2 Electroreduction
Authors: Wicks Joshua , Jue Melinda L. , Beck Victor A. , Oakdale James S. , Dudukovic Nikola A. , Clemens Auston L. , Liang Siwei , Ellis Megan E. , Lee Geonhui , Baker Sarah E. , Duoss Eric B. , Sargent Edward H. 
Published: January 2021

AbstractThe electrosynthesis of value‐added multicarbon products from CO2 is a promising strategy to shift chemical production away from fossil fuels. Particularly important is the rational design of gas diffusion electrode (GDE) assemblies to react selectively, at scale, and at high rates. However, the understanding of the gas diffusion layer (GDL) in these assemblies is limited for the CO2 reduction reaction (CO2RR): particularly important, but incompletely understood, is how the GDL modulates product distributions of catalysts operating in high current density regimes > 300 mA cm−2. Here, 3D‐printable fluoropolymer GDLs with tunable microporosity and structure are reported and probe the effects of permeance, microstructural porosity, macrostructure, and surface morphology. Under a given choice of applied electrochemical potential and electrolyte, a 100× increase in the C2H4:CO ratio due to GDL surface morphology design over a homogeneously porous equivalent and a 1.8× increase in the C2H4 partial current density due to a pyramidal macrostructure are observed. These findings offer routes to improve CO2RR GDEs as a platform for 3D catalyst design.
MnO2‐Based Materials for Environmental Applications
Authors: Yang Ruijie , Fan Yingying , Ye Ruquan , Tang Yuxin , Cao Xiehong , Yin Zongyou , Zeng Zhiyuan 
Published: January 2021

AbstractManganese dioxide (MnO2) is a promising photo–thermo–electric‐responsive semiconductor material for environmental applications, owing to its various favorable properties. However, the unsatisfactory environmental purification efficiency of this material has limited its further applications. Fortunately, in the last few years, significant efforts have been undertaken for improving the environmental purification efficiency of this material and understanding its underlying mechanism. Here, the aim is to summarize the recent experimental and computational research progress in the modification of MnO2 single species by morphology control, structure construction, facet engineering, and element doping. Moreover, the design and fabrication of MnO2‐based composites via the construction of homojunctions and MnO2/semiconductor/conductor binary/ternary heterojunctions is discussed. Their applications in environmental purification systems, either as an adsorbent material for removing heavy metals, dyes, and microwave (MW) pollution, or as a thermal catalyst, photocatalyst, and electrocatalyst for the degradation of pollutants (water and gas, organic and inorganic) are also highlighted. Finally, the research gaps are summarized and a perspective on the challenges and the direction of future research in nanostructured MnO2‐based materials in the field of environmental applications is presented. Therefore, basic guidance for rational design and fabrication of high‐efficiency MnO2‐based materials for comprehensive environmental applications is provided.
Simultaneous Incorporation of Two Types of Azo‐Groups in the Side Chains of a Conjugated D–A Polymer for Logic Control of the Semiconducting Performance by Light Irradiation
Authors: Tian Jianwu , Liu Zitong , Wu Changchun , Jiang Wenlin , Chen Liangliang , Shi Dandan , Zhang Xisha , Zhang Guanxin , Zhang Deqing 
Published: January 2021

AbstractA new design strategy for photoresponsive semiconducting polymer with tri‐stable semiconducting states is reported by simultaneous incorporation of tetra‐ortho‐methoxy‐substituted azobenzene (mAzo) and arylazopyrazole (pAzo) in the side chains. The trans‐to‐cis transformations for mAzo and pAzo groups can sequentially occur within the polymer thin film after sequential 560 and 365 nm light irradiation. Remarkably, the trans–cis isomerization of mAzo and pAzo groups can modulate the thin film crystallinity. Accordingly, the performances of the resulting field‐effect transistors (FETs) can be reversibly modulated, leading to tri‐stable semiconducting states after sequential 560, 365, and 470 nm light irradiation. Therefore, the device performance can be logically controlled by light irradiation at three different wavelengths. In addition, with light irradiation and device current as the input and output signals, the three‐value logic gate by using single FET device can be successfully mimicked.
Supramolecular Assembled Programmable Nanomedicine As In Situ Cancer Vaccine for Cancer Immunotherapy
Authors: Zhang Yu , Ma Sheng , Liu Xinming , Xu Yudi , Zhao Jiayu , Si Xinghui , Li Hongxiang , Huang Zichao , Wang Zhenxin , Tang Zhaohui , Song Wantong , Chen Xuesi 
Published: January 2021

AbstractUsing nanotechnology for improving the immunotherapy efficiency represents a major research interest in recent years. However, there are paradoxes and obstacles in using a single nanoparticle to fulfill all the requirements in the complicated immune activation processes. Herein, a supramolecular assembled programmable immune activation nanomedicine (PIAN) for sequentially finishing multiple steps after intravenous injection and eliciting robust antitumor immunity in situ is reported. The programmable nanomedicine is constructed by supramolecular assembly via host–guest interactions between poly‐[(N‐2‐hydroxyethyl)‐aspartamide]‐Pt(IV)/β‐cyclodextrin (PPCD), CpG/polyamidoamine‐thioketal‐adamantane (CpG/PAMAM‐TK‐Ad), and methoxy poly(ethylene glycol)‐thioketal‐adamantane (mPEG‐TK‐Ad). After intravenous injection and accumulation at the tumor site, the high level of reactive oxygen species in the tumor microenvironment promotes PIAN dissociation and the release of PPCD (mediating tumor cell killing and antigen release) and CpG/PAMAM (mediating antigen capturing and transferring to the tumor‐draining lymph nodes). This results in antigen‐presenting cell activation, antigen presentation, and robust antitumor immune responses. In combination with anti‐PD‐L1 antibody, the PIAN cures 40% of mice in a colorectal cancer model. This PIAN provides a new framework for designing programmable nanomedicine as in situ cancer vaccine for cancer immunotherapy.
Solution Processing of Lithium‐Rich Amorphous Li‐La‐Zr‐O Ion Conductor and Its Application for Cycling Durability Improvement of LiCoO2 Cathode as Coating Layer
Authors: Bui Tan Tan , Yun Boseon , Darko Kwabena , Shin Seung Beom , Kim Jaehyun , Hong Jongin , Lee Minah , Park Sung Kyu , Kim Myung‐Gil 
Published: January 2021

AbstractLithium‐rich amorphous Li‐La‐Zr‐O (a‐Li‐La‐Zr‐O) electrolyte is successfully synthesized using sol–gel processing method. With unlimited compositions of the amorphous structure, lithium‐rich compositions are systematically investigated to determine optimal composition and optimized processing conditions of a‐Li‐La‐Zr‐O coatings. There is an improvement in ionic conductivity of a‐Li‐La‐Zr‐O with Li content increasing, specifically from 3.0 × 10−8 S cm−1 (Li8La2Zr2O11) to 1.18 × 10−6 S cm−1 (Li18La2Zr2O16), thereby resulting in low activation energy. The high‐ionic‐conductivity a‐Li‐La‐Zr‐O is implemented as an artificial solid electrolyte interface coating layer on cathode materials. The a‐Li‐La‐Zr‐O‐coated LiCoO2 (LCO) and LiNi0.8Mn0.1Co0.1O2 (NMC 811) coin cells exhibit better cycling performance than the bare coin cell at the optimum compositional ratio of a‐Li‐La‐Zr‐O. A‐Li‐La‐Zr‐O can be a promising material for solid electrolyte battery and a potential coating layer for the modification of cathode surface.
Multimodal Spectroscopic Study of Surface Termination Evolution in Cr2TiC2Tx MXene
Authors: Hart James L. , Hantanasirisakul Kanit , Lang Andrew C. , Li Yuanyuan , Mehmood Faisal , Pachter Ruth , Frenkel Anatoly I. , Gogotsi Yury , Taheri Mitra L. 
Published: January 2021

AbstractControl of surface functionalization of MXenes holds great potential, and in particular, may lead to tuning of magnetic and electronic order in the recently reported magnetic Cr2TiC2Tx. Here, vacuum annealing experiments of Cr2TiC2Tx are reported with in situ electron energy loss spectroscopy and novel in situ Cr K‐edge extended energy loss fine structure analysis, which directly tracks the evolution of the MXene surface coordination environment. These in situ probes are accompanied by benchmarking synchrotron X‐ray absorption fine structure measurements and density functional theory calculations. With the etching method used here, the MXene has an initial termination chemistry of Cr2TiC2O1.3F0.8. Annealing to 600 °C results in the complete loss of F, but O termination is thermally stable up to (at least) 700 °C. These findings demonstrate thermal control of F termination in Cr2TiC2Tx and offer a first step toward termination engineering this MXene for magnetic applications. Moreover, this work demonstrates high energy electron spectroscopy as a powerful approach for surface characterization in 2D materials.
Non‐Local Reconfigurable Sparse Metasurface: Efficient Near‐Field and Far‐Field Wavefront Manipulations
Authors: Popov Vladislav , Ratni Badreddine , Burokur Shah Nawaz , Boust Fabrice 
Published: January 2021

AbstractIn recent years, metasurfaces have shown extremely powerful abilities for manipulation of electromagnetic waves. However, the local electromagnetic response of conventional metasurfaces yields an intrinsic performance limitation in terms of efficiency, minimizing their implementation in real‐life applications. The efficiency of reconfigurable metasurfaces further decreases because of the high density of meta‐atoms, reaching 74 meta‐atoms per λ2 area, incorporating lossy tunable elements. To address these problems, strong electromagnetic non‐local features are implemented in a sparse metasurface composed of electronically reconfigurable meta‐atoms. As a proof‐of‐concept demonstration, a dynamic sparse metasurface having as few as 8 meta‐atoms per λ2 area is experimentally realized in the microwave domain to control 2D wavefronts in both near‐field and far‐field regions for focusing and beam‐forming, respectively. The proposed metasurface with its sparsity not only facilitates design and fabrication, but also opens the door to high‐efficiency real‐time reprogrammable functionalities in beam manipulations, wireless power transfer, and imaging holography.
Recent Advances on Molecular Crystalline Luminescent Materials for Optical Waveguides
Authors: Wu Siqin , Zhou Bo , Yan Dongpeng 
Published: January 2021

AbstractMolecule‐based fluorescent materials with optical waveguides (MFOWs) have attracted great research interest in the optoelectronic and photonic fields due to their unique photoluminescence properties. Theoretically, the waveband of propagated light within the MFOWs can cover the entire visible light region, which has been one of the important branches in micro/nanophotonics. In this review, the research progress of MFOWs during the last few years, including the basic emission parameters, waveguiding mechanisms, and design methods including adjustments of size, dimension, and shape at the micro/nano‐scales is systematically summarized. New emerging materials (such as flexible nanostructures, molecular cocrystals, and organic–inorganic hybrids) are described towards the high‐performance MFOWs applications. Although tremendous researches for developing MFOWs have been conducted, there remain several dilemmas, such as the deep understanding on elucidated mechanisms and the difficulty for commercialization. Thus, this work also presents the existing challenges and insightful trends, which offer potential guidance for the design and development of MFOWs in future.
Enhanced Energy Transfer from Nitrogen‐Vacancy Centers to Three‐Dimensional Graphene Heterostructures by Laser Nanoshaping
Authors: Liu Jing , Hu Yaowu , Kumar Prashant , Liu Xingtao , Irudayaraj Joseph M. K. , Cheng Gary J. 
Published: January 2021

AbstractGraphene, a well‐studied 2D material, is used to tailor the emission behavior of proximal light emitters by controlling the energy flow to modulate the related relaxation rates, with potentials in fields of biosensing and photovoltaics. Good interface between emitters and 2D materials are important to efficiently modulate the photon emission behavior. However, seamless integration of quantum light emitters and atomically thin materials is challenging due to fabrication limitation. In this paper, the utilization of laser nanoshaping approaches to “wrap” the atomically thin graphene on nanodiamond particles is reported. Compared with 2D layout, the 3D integration enhances the energy transfer by 45%. Furthermore, it is found that the energy transfer efficiency of nitrogen‐vacancy (NV) centers to the 3D graphene can reach a maximum value of 80% over a long distance (≈25 nm), under intense laser excitation. The authors’ analysis indicates that the photon‐generated carrier density of graphene enhances the nonradiative decay rate of NV centers. Besides contributing new insight on the fundamentals of interactions between graphene and quantum emitters, the effort undertaken furthermore holds tremendous promise in developing the graphene‐based nano‐cavities for various applications ranging from sensing, to photovoltaics, to lasing, and to quantum communications.
Realizing Near‐Infrared Laser Dyes through a Shift in Excited‐State Absorption
Authors: Aoki Reiko , Komatsu Ryutaro , Goushi Kenichi , Mamada Masashi , Ko Soo Young , Wu Jeong Weon , Placide Virginie , D'Aléo Anthony , Adachi Chihaya 
Published: January 2021

AbstractThe development of near‐infrared (NIR) light sources has attracted much interest due to their attractive applications, such as biosensing and light detection and ranging (LiDAR). In particular, organic semiconductor laser diodes with NIR emission are emerging as a next generation technology. However, organic NIR emitters have generally suffered from a low quantum yield, which has resulted in only a few examples of organic solid‐state NIR lasers. In this study, the authors demonstrate a highly efficient NIR emitter based on a boron difluoride curcuminoid structure, which shows a high photoluminescence (PL) quantum yield (ΦPL) at >700 nm and a high fluorescence radiative rate constant in a solid‐state film. Amplified spontaneous emission and lasing occurs at >800 nm with very low thresholds. The large redshift of the stimulated emission is attributed to the transition from the lowest excited state to the different vibrational levels of the ground state owing to the overlap between the emission and the singlet–singlet excited‐state absorption.
Formal [3+2] Cycloaddition Between in situ Formed 1,4‐Benzodiazepin‐2‐One‐Based Azomethine Ylides and Azodicarboxylic Acid Derivatives: Diastereoselective Synthesis of Spiro‐1,4‐Benzodiazepin‐2‐Ones
Authors: Fan Xiao‐Zu , Wu Hui‐Hui , Tang Zhe , Zhang Heng , Cai Lu‐Yu , Bi Xiao‐Fan , Zhao Hong‐Wu 
Published: January 2021

AbstractIn the presence of PhCO2H (20 mol%), the formal [3+2] cycloaddition between in situ formed 1,4‐benzodiazepin‐2‐one‐based azomethine ylides and azodicarboxylic acid derivatives proceeded readily, thus leading to the formation of trans‐configured spiro‐1,4‐benzodiazepin‐2‐ones in up to 98% chemical yield with >20:1 dr. The relative configuration of the title compounds was unambiguously determined by means of X‐ray single crystal structure analysis. The reaction mechanism was hypothesized to account for the diastereoselective formation of the isolated spiro‐1,4‐benzodiazepin‐2‐ones.magnified image
Monolithic‐Integrated Multiplexed Devices Based on Metasurface‐Driven Guided Waves
Authors: Ha Yingli , Guo Yinghui , Pu Mingbo , Li Xiong , Ma Xiaoliang , Zhang Zuojun , Luo Xiangang 
Published: January 2021

AbstractThe appearance of metasurfaces has solved the difficult problems of bulkiness, the complexity of traditional optics, and arbitrary optical response controlling. However, most free‐space metasurfaces and existing integrated metadevices do not meet the criteria of full on‐chip integration toward low loss and high information transmission capacity. Here, by decorating silicon‐on‐insulator waveguides with metasurfaces, one can realize the arbitrary phase and intensity manipulation of guided waves. Four‐channel multiplexer is demonstrated with inherent advantages of low loss and independent transmission of electromagnetic waves in x and y directions. As proof‐of‐concept demonstrations, monolithic‐integrated multiplexed orbital angular momentum (OAM) and holographic generators are developed at 1550 nm to realize high information transmission capacity, low loss, and low crosstalk. Specifically, when the electromagnetic wave is incident from x, −x, y, and −y directions, four kinds of OAM mode with different topological charge values (−1, +1, +2, and −2), and four different holographic images of the letter “U,” “C,” “A,” and “S” can be obtained with the four‐channel multiplexed OAM generator and holographic display device, respectively. The design methods proposed here are expected to open a new perspective for future versatile utilization of driven guided waves to achieve numerous functionalities.
Bilayer Tellurene: A Potential p‐Type Channel Material for Sub‐10 nm Transistors
Authors: Li Qiuhui , Xu Lin , Liu Shiqi , Yang Jie , Fang Shibo , Li Ying , Ma Jiachen , Zhang Zhiyong , Quhe Ruge , Yang Jinbo , Lu Jing 
Published: January 2021

AbstractThe emerging two‐dimensional (2D) tellurium (tellurene) has attracted much attention due to its high carrier transportability and prominent air stability. Micrometer‐scale bilayer (BL) tellurene field‐effect transistors (FETs) are successfully fabricated with a large on/off current ratio of about 105. Here, the transport properties of both the n‐ and p‐type double‐gated sub‐10 nm BL tellurene metal‐oxide‐semiconductor FETs (MOSFETs) are systematically explored by using ab initio quantum transport simulation. The optimized 5, 7, and 9 nm gate‐length p‐type x‐ and y‐directed BL tellurene MOSFETs with a proper underlap and negative capacitance dielectric can meet or nearly meet the on‐state current, delay time, power dissipation, and energy‐delay product requirements of the International Technology Roadmap for Semiconductors for the 2022–2028 horizons for high‐performance applications. This renders BL tellurene to join the air‐stable channel candidate for the p‐type sub‐10 nm transistors.