bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hexafluoroisopropyl Trifluoromethanesulfonate‐Driven Easily Li+ Desolvated Electrolyte to Afford Li||NCM811 Cells with Efficient Anode/Cathode Electrolyte Interphases
Authors: Li Xin , Liu Jiandong , He Jian , Wang Huaping , Qi Shihan , Wu Daxiong , Huang Junda , Li Fang , Hu Wei , Ma Jianmin 
Published: June 2021

AbstractSolid electrolyte interphase (SEI) and cathode electrolyte interphase (CEI) with optimized components and structures are considered to be crucial for lithium‐ion batteries. Here, gradient lithium oxysulfide (Li2SOx, x = 0, 3, 4)/uniform lithium fluoride (LiF)‐type SEI is designed in situ by using hexafluoroisopropyl trifluoromethanesulfonate (HFPTf) as electrolyte additive. HFPTf is more likely to be reduced on the surface of Li anode in electrolytes due to its high reduction potential. Moreover, HFPTf can make Li+ desolvated easily, leading to the increase in the flux of Li+ on the surface of Li anode to avoid the growth of Li dendrites. Thus, the cycling stability of Li||Li symmetric cells is improved to be 1000 h at 0.5 mA cm−2. In addition, HFPTf‐contained electrolyte could make Li||NCM811 batteries with a capacity retention of 70% after 150 cycles at 100 mA g−1, which is attributed to the formation of uniform and stable CEI on the cathode surface for hindering the dissolvation of metal ions from the cathode. This study provides effective insights on the strong ability of additives to adjust electrolytes in “one phase and two interphases” (electrolyte and SEI/CEI).
Organic Semiconducting Macromolecular Dyes for NIR‐II Photoacoustic Imaging and Photothermal Therapy
Authors: Yin Chao , Li Xiaozhen , Wang Yi , Liang Yuying , Zhou Shan , Zhao Pengchao , Lee Chun‐Sing , Fan Quli , Huang Wei 
Published: June 2021

AbstractOwing to the unique advantages of photoacoustic imaging (PAI) and photothermal therapy (PTT) conducted over the near‐infrared‐II (NIR‐II) window, the development of high‐efficiency optical agents with NIR‐II light responsiveness is of great significance. Despite the diversity of optical agents developed for NIR‐II PAI and PTT, most of them are based on inorganic nanomaterials and small molecular dyes, whose biosafety and photostability need to be further assessed, respectively. Organic semiconducting macromolecular dyes (OSMDs) featuring a large semiconducting backbone are becoming alternative candidates for NIR‐II PAI and PTT owing to their reliable biocompatibility, durable photostability, and ideal photothermal conversion capability. This paper reviews the current progress of OSMD‐based PAI and PTT in the NIR‐II optical window. The three main types of OSMDs with different skeleton architectures are introduced, and their applications for NIR‐II PAI (tumor imaging, stem cell tracking, and vasculature imaging) and PTT (tumor ablation) are described. Viable strategies for further improving the NIR‐II PAI performance of OSMDs are discussed. Finally, some major issues faced by OSMDs in NIR‐II PAI and PTT are raised, and the future development directions of OSMDs are analyzed.
Reversible Writing/Re‐Writing Polymeric Paper in Multiple Environments
Authors: Chen Chi , Zhao Xinkun , Chen Yujie , Wang Xinyue , Chen Zhen , Li Hua , Wang Kaifeng , Zheng Xu , Liu Hezhou 
Published: June 2021

AbstractCompared with traditional paper relying on cellulose, the polymeric paper written by light can satisfy more multi‐environmental stability and reusability for sustainable development. Herein, proposed for the first time, a novel multifunctional polymeric paper with a patch‐sewing structure is designed, presenting the reversible writing/re‐writing performance. Meanwhile, a series of Fe‐based oxides with various submicron structures inherited from metal–organic framework templates are reported, in which the optimum one exhibited 95.04% absorbance from the finite difference time domain simulation and realized photothermal conversion instantaneously (soaring to 300 °C within 38 s). Given the distinguished mechanical properties (the tensile strength of 21.34 MPa and elongation at break of 546.06%), shape‐memory ability, and multi‐environmental stability, the composites are perfect for information recording. Due to the addition of the liquid crystal phase serving as the ink on the paper, the stress concentration and destruction can be recorded on the surface while it can recover to the initial situation by near‐infrared irradiation. Moreover, the remote writing with precision triggered by a focused light source can be achieved in multiple situations (air, water, and ice), which paved the way for the next generation of paper, especially in extreme conditions like deep‐water or aerospace.
Facet Engineering to Regulate Surface States of Topological Crystalline Insulator Bismuth Rhombic Dodecahedrons for Highly Energy Efficient Electrochemical CO2 Reduction
Authors: Xie Huan , Zhang Tan , Xie Ruikuan , Hou Zhufeng , Ji Xuecong , Pang Yongyu , Chen Shaoqing , Titirici Maria‐Magdalena , Weng Hongming , Chai Guoliang 
Published: June 2021

AbstractBismuth (Bi) is a topological crystalline insulator (TCI), which has gapless topological surface states (TSSs) protected by a specific crystalline symmetry that strongly depends on the facet. Bi is also a promising electrochemical CO2 reduction reaction (ECO2RR) electrocatalyst for formate production. In this study, single‐crystalline Bi rhombic dodecahedrons (RDs) exposed with (104) and (110) facets are developed. The Bi RDs demonstrate a very low overpotential and high selectivity for formate production (Faradic efficiency >92.2%) in a wide partial current density range from 9.8 to 290.1 mA cm−2, leading to a remarkably high full‐cell energy efficiency (69.5%) for ECO2RR. The significantly reduced overpotential is caused by the enhanced *OCHO adsorption on the Bi RDs. The high selectivity of formate can be ascribed to the TSSs and the trivial surface states opening small gaps in the bulk gap on Bi RDs, which strengthens and stabilizes the preferentially adsorbed *OCHO and mitigates the competing adsorption of *H during ECO2RR. This study describes a promising application of Bi RDs for high‐rate formate production and high‐efficiency energy storage of intermittent renewable electricity. Optimizing the geometry of TCIs is also proposed as an effective strategy to tune the TSSs of topological catalysts.
Hypervalent Iodine Compounds as Versatile Reagents for Extremely Efficient and Reversible Patterning of Graphene with Nanoscale Precision
Authors: Bao Lipiao , Zhao Baolin , Yang Bowen , Halik Marcus , Hauke Frank , Hirsch Andreas 
Published: June 2021

AbstractRational patterning and tailoring of graphene relies on the disclosure of suitable reagents for structuring the target functionalities on the 2D‐carbon network. Here, a series of hypervalent iodine compounds, namely, 1‐chloro‐1,2‐benziodoxol‐3(1H)‐one, 1,3‐dihydro‐1‐hydroxy‐3,3‐dimethyl‐1,2‐benziodoxole, and 3,3‐dimethyl‐1‐(trifluoromethyl)‐1,2‐benziodoxole is reported to be extremely efficient for a diversified graphene patterning. The decomposition of these compounds generates highly reactive Cl, OH, and CF3 radicals exclusively in the irradiated areas, which subsequently attach onto the graphene leading to locally controlled chlorination, hydroxylation, and trifluoromethylation, respectively. This is the first realization of a patterned hydroxylation of graphene, and the degrees of functionalization of the patterned chlorination and trifluoromethylation are both unprecedented. The usage of these mild reagents here is reasonably facile compared to the reported methods using hazardous Cl2 or ICl and allows for sophisticated pattern designs with nanoscale precision, promising for arbitrary nanomanipulation of graphene's properties like hydrophilicity and conductivity by the three distinct functionalities (Cl, OH, and CF3). Moreover, the attachment of functional entities to these highly functionalized graphene nanoarchitectures is fully reversible upon thermal annealing, enabling a full writing/storing/reading/erasing control over the chemical information stored within graphene. This work provides an exciting clue for target 2D functionalization and modulation of graphene by using suitable hypervalent iodine compounds.
Structural and Trap‐State Density Enhancement in Flash Infrared Annealed Perovskite Layers
Authors: Brunova Alica , Vegso Karol , Nadazdy Vojtech , Nadazdy Peter , Subair Riyas , Jergel Matej , Majkova Eva , Pandit Pallavi , Roth Stephan V. , Krasnansky Alexander , Hinderhofer Alexander , Schreiber Frank , Tian Jianjun , Siffalovic Peter 
Published: June 2021

AbstractPerovskite solar cells are well‐known for their high energy conversion efficiency, low‐temperature processing, and cost‐effective production. Flash infrared annealing (FIRA) of slot‐die cast perovskite precursors offers an attractive manufacturing route using high‐throughput roll‐to‐roll technology. Despite the recent progress in FIRA perovskite annealing, the optimal composition of the perovskite precursor is yet to be developed. Here, the effect of methylammonium chloride (MACl) on the perovskite structure and trap‐state density as a function of the FIRA annealing time is investigated. In situ real‐time grazing‐incidence wide‐angle X‐ray scattering (GIWAXS) is employed to monitor the perovskite layer formation during FIRA annealing with millisecond temporal resolution. In addition, the density of states in the bandgap is estimated using ex situ energy‐resolved electrochemical impedance spectroscopy. Evidence is found that adding 10% MACl into the perovskite precursor solution significantly improves the crystallographic orientation of the perovskite layers while reducing the trap‐state density by one order of magnitude. In addition, using time‐resolved GIWAXS, the most favorable time window for the FIRA processing of perovskite films with the lowest mosaicity and trap‐state density is identified. The results are of general importance for elucidating the appropriate temporal windows in complex and fast‐evolving crystallization processes.
In‐Situ Observation of the Formation of NiSi/Ni2Si Heterojunction in SiGe Nanowire with Al2O3 Diffusion Barrier Layer
Authors: Lee Yu‐Chuan , Lyu Lian‐Ming , Lu Ming‐Yen 
Published: June 2021

AbstractIn complementary metal‐oxide‐semiconductor technology, the metal silicides/germanides have prominent advantages such as low resistivity, high thermal and chemical stability. Here, a study to probe the phase transformations and the diffusion behaviors of Ni in Si1‐xGex nanowire (NW) by in situ transmission electron microscopy is conducted. The Si1‐xGex NWs are dispersed on Si3N4 membrane and contacted with Ni by E‐beam lithography process for in situ study. The sample is heated to 723 K, Ni is diffused into Si1‐xGex NW and Ni2Si is formed accordingly. The diffusion mechanism is confirmed to be reaction‐controlled and the activation energy can be extracted to be 0.708 eV. On the other hand, in this study Al2O3 layer‐coated Si1‐xGex NW is probed for comparison, while the Al2O3 layer serves as the diffusion barrier to modulate the diffusion rate of Ni. This increases the activation energy to 1.38 eV. Importantly, it is found that the NiSi/Ni2Si heterojunction is formed at the diffusion front. The results provide the insights for fabrication of semiconducting devices.
Interface Defect Engineering of a Large‐Scale CVD‐Grown MoS2 Monolayer via Residual Sodium at the SiO2/Si Substrate
Authors: Han Sang Wook , Yun Won Seok , Woo Whang Je , Kim Hyungjun , Park Jusang , Hwang Young Hun , Nguyen Tri Khoa , Le Chinh Tam , Kim Yong Soo , Kang Manil , Ahn Chang Won , Hong Soon Cheol 
Published: June 2021

AbstractAlkali metal halide‐assisted chemical vapor deposition (CVD) methods can produce wafer‐scale uniform monolayer transition metal dichalcogenides (TMDs). Further defect engineering is necessary to obtain high‐performance functional devices. While defect engineering has focused on the surface of the monolayer TMDs or the contact property, interface defect engineering is rare and non‐trivial. Based on a NaCl‐assisted CVD‐grown large‐scale uniform MoS2 monolayer on SiO2/Si substrate, a trace amount of Na cations is present, residing at the SiO2 substrate during the CVD‐growth process and contributes to the n‐type doping into the supported monolayer MoS2. Furthermore, the residual Na cations are electrically moved toward the bottom side of monolayer MoS2 to passivate the interfacial defects.
Slot‐Die Coating of All Organic/Polymer Layers for Large‐Area Flexible OLEDs: Improved Device Performance with Interlayer Modification
Authors: C Amruth , Dubey Deepak K. , Pahlevani Majid , Welch Gregory C. 
Published: June 2021

AbstractOrganic light‐emitting diodes (OLEDs) fabricated on flexible transparent substrates have found application in displays, lighting, and signage. Optimization of the fabrication procedures is critical for commercialization to maximize performance and reduce costs. Utilization of the slot‐die coating technique, a solution‐processing roll‐to‐roll method, has emerged as a viable method to manufacture flexible OLED devices. Here, the fabrication of flexible OLEDs via the slot‐die coating technique under ambient condition is reported. The OLEDs have a simple architecture of polyethylene terephthalate (PET)/indium–tin oxide (ITO)/hole injection layer (HIL)/emissive layer (EML)/electron injection layer (EIL)/Ag, where poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) is used as the HIL, Super Yellow (SY, poly(1,4‐phenylenevinylene) copolymer) is used as the EML, and poly((9,9‐bis(3′‐(N,N‐dimethylamino)propyl)‐2,7‐fluorene)‐alt‐2,7‐(9,9‐dioctylfluorene)) (PFN) is used as the EIL. The optimization of the PFN layer using slot‐die coating technique is focused by varying solvent, solvent additives, substrate temperature, and coating speeds. The OLEDs that have PFN layers processed with the known solvent additives, 1,8‐diiodooctane (DIO) or diphenyl ether (DPE), show a performance increase compared to OLEDs based on PFN layers processed with no solvent additives. Finally, large‐area multicolor OLEDs are constructed with organic/polymer layers being slot‐die coated in sequence, of which all display homogeneous luminance under bending/folding conditions, highlighting the potential of this simple device structure and processing method.
Tailoring Electropolymerized Poly(3,4‐ethylenedioxythiophene) Films for Oxygen Reduction Reaction
Authors: Nayak Prem D. , Ohayon David , Wustoni Shofarul , Inal Sahika 
Published: June 2021

AbstractOxygen reduction reaction (ORR) is a critical process for several electrocatalytic and photocatalytic devices. Poly(3,4‐ethylenedioxythiophene), PEDOT, is an efficient ORR catalyst, with hydrogen peroxide (H2O2) being the primary reaction product. Although H2O2 is a green fuel for batteries and fuel cells and used as an industrial oxidant, it is toxic for living systems. As such, its production should be limited when PEDOT films are used in bioelectronic devices. In this work, the ORR behavior of a series of electropolymerized PEDOT films is investigated. By varying the counterion (monomeric vs polymeric), including a hydroxyl‐terminated EDOT monomer in the polymer architecture, or adding a conductivity enhancer in the reaction mixture, the authors aim to understand the parameters governing the ORR properties. It is that the polymer's pristine doping level—influenced by counterion type and the presence of the conductivity enhancer—controls the ORR pathway in PEDOT films. High levels of intrinsic doping led to films with H2O2 as the major ORR product. This work suggests strategies for the design of conducting polymers with optimized performance for electrocatalytic applications and minimized production of harmful chemicals for bioelectronic devices.
Thin‐Film Devices for Active Pixel Sensor Schemes Enabling High Density and Large‐Area Sensors
Authors: Avila‐Avendano Carlos , Mejia Israel , Reyes‐Banda Martin G. , Lamont Jair Garcia , Pham Christopher , Caraveo‐Frescas Jesus A. , Gnade Bruce E. , Quevedo‐Lopez Manuel A. 
Published: June 2021

AbstractA novel and scalable method enabling the integration of dissimilar thin‐film devices for high density and large‐area sensors is demonstrated. The method is validated by integrating CdS/CdTe P‐N thin‐film diodes with poly‐Si thin‐film transistors (TFTs) in an active pixel sensor (APS) scheme. These devices have been used separately in low‐cost and large‐area applications such as liquid‐crystal displays (Poly‐TFTs) and solar cells (CdS/CdTe) and the methods allow a seamless integration that eliminates the use of discrete pixel‐to‐pixel bumping interconnections. APSs, consisting of a cascode TFT amplifier and a CdS/CdTe diode, are evaluated using pulsed light sources under several wavelengths and intensities. The results demonstrated a responsivity increase of >100× for the integrated sensors and well‐defined signal amplitude, as desirable for energy and intensity monitoring. The method enables the use of two dissimilar and remarkable devices in a wide range of applications such as X‐ray imagers, gamma‐ray detectors, and thermal neutron detectors, while offering large‐area and low‐cost compatibility. More importantly, the integrity and reliability of the diodes and TFTs are not affected by the integration process.
Ambipolar Charge Storage in Type‐I Core/Shell Semiconductor Quantum Dots toward Optoelectronic Transistor‐Based Memories
Authors: hu Hao , Wen Guohao , Wen Jiamin , Huang Long‐Biao , Zhao Meng , Wu Honglei , Sun Zhenhua 
Published: June 2021

AbstractEfficient charge storage media play a pivotal role in transistor‐based memories and thus are under intense research. In this work, the charge storage ability of type‐I InP/ZnS core/shell quantum dots is well revealed through studying a pentacene‐based organic transistor with the quantum dots (QDs) integrated. The quantum well‐like energy band structure enables the QDs to directly confine either holes or electrons in the core, signifying a dielectric layer‐free nonvolatile memory. Especially, the QDs in this device can be charged by electrons using light illumination as the exclusive method. The electron charging process is ascribed to the photoexcitation process in the InP‐core and the hot holes induced. The QDs layer demonstrates an electron storage density of ≈5.0 × 1011 cm−2 and a hole storage density of ≈6.4 × 1011 cm−2. Resultingly, the output device shows a fast response speed to gate voltage (10 µs), large memory window (42 V), good retention (>4.0 × 104 s), and reliable endurance. This work suggests that the core/shell quantum dot as a kind of charge storage medium is of great promise for optoelectronic memories.
Molecular PET/CT Profiling of ACE2 Expression In Vivo: Implications for Infection and Outcome from SARS‐CoV‐2
Authors: Zhu Hua , Zhang Hanwen , Zhou Nina , Ding Jin , Jiang Jinquan , Liu Teli , Liu Ziyu , Wang Feng , Zhang Qian , Zhang Zhuochen , Yan Shi , Li Lei , Benabdallah Nadia , Jin Hongjun , Liu Zhaofei , Cai Lisheng , Thorek Daniel L. J. , Yang Xing , Yang Zhi 
Published: June 2021

AbstractRapid progress has been made to identify and study the causative agent leading to coronavirus disease 2019 (COVID‐19) but many questions including who is most susceptible and what determines severity remain unanswered. Angiotensin‐converting enzyme 2 (ACE2) is a key factor in the infection process of severe acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2). In this study, molecularly specific positron emission tomography imaging agents for targeting ACE2 are first developed, and these novel agents are evaluated in vitro, in preclinical model systems, and in a first‐in‐human translational ACE2 imaging of healthy volunteers and a SARS‐CoV‐2 recovered patient (NCT04422457). ACE2 expression levels in different organs in live subjects are quantitatively delineated and observable differences are measured in the patient recovered from COVID‐19. Surprising sites of uptake in the breast, reproductive system and very low uptake in pulmonary tissues are reported. This novel method can add a unique tool to facilitate SARS‐CoV‐2 related research and improve understanding of this enigmatic disease. Molecular imaging provides quantitative annotation of ACE2, the SARS‐CoV‐2 entry receptor, to noninvasively monitor organs impacted by the COVID‐19.
Time‐Dependent Imprint in Hf0.5Zr0.5O2 Ferroelectric Thin Films
Authors: Takada Kenshi , Takarae Shuya , Shimamoto Kento , Fujimura Norifumi , Yoshimura Takeshi 
Published: June 2021

AbstractThe discovery of the HfO2‐based ferroelectric films has opened new opportunities for using this silicon‐compatible ferroelectric material to realize low‐power logic circuits and high‐density non‐volatile memories. The functional performances of ferroelectrics are intimately related to their dynamic response to external stimuli, such as electric fields at finite temperatures. In the case of HfO2‐based films, the time‐dependent imprint and wake‐up effect, which distinguish them from conventional ferroelectrics, play important roles in understanding the remaining reliability issues, such as insufficient endurance. In this study, the time‐dependent imprint process is carefully investigated using Hf0.5Zr0.5O2 (HZO) films with different ferroelectric properties and defect density. The amount of redistributed charge, which causes imprint during polarization retention, is affected by the remanent polarization of the ferroelectric layer, suggesting that the depolarization field corresponding to the remanent polarization generates and works as a driving force of charge redistribution. The time‐dependent measurement of the imprint distinguishes the origins of charge redistribution processes, which have different time constants. In addition, the correlation between the amount of redistributed charge and the dielectric relaxation of the HZO films is discussed. Correlations are identified between the redistributed charge and the dielectric relaxation, indicating that the mobile charge contributes to the time‐dependent imprint.
Prospect of Spintronics in Neuromorphic Computing
Authors: Zhou Jing , Chen Jingsheng 
Published: June 2021

AbstractNeuromorphic computing emulates a biological brain at different levels of the computer hierarchy by exploiting brain‐inspired principles in designing novel devices, algorithms, and architectures. It is believed to have a lower power budget and a higher efficiency in performing cognitive tasks, and is arguably the most promising approaches for next‐generation artificial intelligence. Despite the potentials, progress of neuromorphic computing is constrained by a lack of dedicated hardware. Spintronics is a fast‐evolving discipline that exploits the spin degree of freedom in electronics. The interplay of magnetic and electrical properties of spintronic devices gives rise to a wide range of amazing phenomena, which are both intrinsically conducive to neuromorphic computing and highly compatible with conventional manufacturing technologies. Here, the development of neuromorphic computing with reference to spintronics is reviewed. The state‐of‐the‐art spintronic technologies, such as the magnetic tunnel junction, spin–orbit torque, domain wall propagation, magnetic skyrmions, and antiferromagnet, are highlighted and how they can used for artificial neurons and synapses in different artificial neural networks are discussed. The technical challenges to be overcome for realizing more powerful all‐spin artificial neural networks are also evaluated.