bluuebunny/crossref_metadata_2025 huggingface dataset:
Polymer Nanocomposites Based on TiO2as a Reinforcing Agent: An Overview
Authors: Nawaz Hifza , Umar Muhummad , Maryam Reeha , Nawaz Iqra , Razzaq Humaira , Malik Tabassum , Liu Xuqing
Published: September 2022

Titania (TiO2) is one of the most versatile materials in the field of polymer science and technology. In recent years, a large area of research has focused on the combination of TiO2with polymers and other carbon nanostructures. Literature reports suggest that nanoscale TiO2reinforcement gives rise to new optical, electrical, and physiochemical properties attained at extremely low TiO2content, thus making these nanocomposites (NCs) a promising new class of materials. This review summarizes the contemporary views on the state‐of‐the‐art synthesis and applications of TiO2‐based polymer nanocomposites having different polymer matrices. The merits and demerits of various fabrication techniques have been presented alongside. Moreover, the worth of polymer/TiO2NCs for various applications such as environmental remediation, i.e., water treatment and gas separation, biomedical, sensing, and energy sector has also been discussed. Based on the latter, one can safely anticipate that these materials hold the promise for commercial applications in widespread fields.
Adhesive Hybrid Interpenetrating Network Hydrogel‐Based Detector to Monitor Solar Radiation Dose Required for Plant Growth
Authors: Hu Neng , Shi Lei , Ji Shangchao , Wang Weijia , Lei Lin , Fan Huiqing , Müller-Buschbaum Peter , Zhong Qi
Published: September 2022

An adhesive and visualized hydrogel‐based detector is designed to monitor the solar radiation dose required for plant growth by the discoloration of methylene blue (MB) under sunshine. The detector is based on hybrid hydrogels prepared from photoinitiated polymerization. The combination of polypropylene (PP) fabrics acting as a substrate and the photoinitiated polymerization on the graphitic carbon nitride (g‐C3N4) surface enables a smaller thickness and a more homogenous distribution of the g‐C3N4 nanosheets. Thus, the hybrid interpenetrating network (IPN) hydrogel on the PP fabrics with a thickness of 1.5 mm presents an improved photodegradation capability. In addition, better mechanical properties and lower weight of the hydrogel‐based detector are achieved by the presence of the PP fabrics. In combination with the stickiness from a polyurethane resin acting as glue, the obtained detector can be easily pasted on the leaf of a plant as demonstrated for the example of Epipremnum aureum. The radiation dose exposed to the leaves can be accurately traced from the change in color of the detector to ensure a sufficient radiation for plant growth and avoid possible burn to the leaves under sunshine.
Antimicrobial Finish of Polyethersulfone Membranes: Sticking Photosensitizers‐Like Marine Mussels Would Do
Authors: Grafl Anna , Müller Alexander , Preuß Annegret , Röder Beate , Börner Hans. G.
Published: September 2022

Biofouling is one of the most serious problems in membrane filtration systems for water treatment. An easily applicable antimicrobial finish of polyethersulfone (PES) filter membranes is shown by derivatizing an approved chlorin photosensitizer drug with adhesive ortho‐catechol functionalities as known from l‐3,4‐dihydroxyphenylalanin (Dopa) residues of marine mussel glues. The chemical structure of the second‐generation photosensitizer 5,10,15,20‐tetrakis(3‐hydroxyphenyl)chlorin (m‐THPC) is modified by 2‐iodoxybenzoic acid (IBX) oxidation, transforming the peripheric meta‐phenols of m‐THPC into ortho‐catechols, and thus improving the adsorption properties of m‐THPC derivatives onto PES material. Stable coatings are formed that preserve chlorin's capability to generate singlet oxygen under visible light illumination. The modification of one or two phenol groups out of the four m‐THPC substituents leads to an optimum in the generation of active singlet oxygen, and thus the finish significantly reduces the bacterial growth of gram‐negative Escherichia coli and gram‐positive Micrococcus luteus on the PES membranes.
Multi‐dimensional Self‐splitting Behaviors for Improving Wet Attachment on Nonuniform Bioinspired Pillar Surface
Authors: Zhang Liwen , Guo Yurun , Wang Yan , Liang Jing , Zhou Yu , Liu Xiaolin , Zhang Deyuan , Chen Huawei
Published: September 2022

Robust and controllable wet attachment like tree frog toe pads attracts worldwide attention owing to potential applications in wet climbing robots, medical devices, and wearable sensors. Instead of conventional uniform pillars, nonuniform pillar arrays with features of inclination and gradients are discovered as typical structures on tree frog toe pads, whereas their effects on wet friction have been ignored. Micro‐nano in situ observation demonstrates that such a nonuniform pillar surface brings about unique multi‐dimensional self‐splitting behaviors in interfacial liquid films and contact stress distribution to enhance the wet attachment. The self‐splitting of the interfacial liquid film breaks the thick large area liquid film into an immense number of more uniform and robust tiny thin liquid bridges. Furthermore, the contact stress is redistributed by the inclined and gradient pillar array with contact stress self‐splitting, where the peak normal separating stress decreases ≈91% and lateral stress transmission increases ≈63%. Such contact stress self‐splitting further improves the liquid film self‐splitting by forming sturdy thin liquid films even under a larger load, which generates more robust capillarity with enhanced strong friction. Finally, theoretical models are built for the multi‐dimensional self‐splitting enhanced wet attachment, and applications in robotic and medical fields are performed to validate its feasibility.
Tumor Response and NIR‐II Photonic Thermal Co‐Enhanced Catalytic Therapy Based on Single‐Atom Manganese Nanozyme
Authors: Ye Jin , Lv Wubin , Li Chunsheng , Liu Shuang , Yang Xing , Zhang Jiangwei , Wang Chen , Xu Jiating , Jin Guanqiao , Li Bin , Fu Yujie , Liang Xinqiang
Published: September 2022

Single‐atom nanozymes (SAzymes) can effectively mimic the metal active centers of natural enzymes at the atomic level owing to their atomically dispersed active sites, thereby maximizing atom utilization efficiency and density of active sites. Hence, SAzymes can be considered the most promising candidates to replace natural enzymes. Herein, a PEGylated mesoporous Mn‐based single‐atom nanozyme (PmMn/SAE) employing a coordination‐assisted polymerization pyrolysis strategy that uses polydopamine for photothermal‐augmented nanocatalytic therapy is designed. PmMn/SAE exhibits excellent multiple enzymatic performance, including catalase‐like, oxidase‐like, and peroxidase (POD)‐like performance, due to the atomically dispersed Mn active species. As a result, PmMn/SAE not only catalyzes the decomposition of endogenous H2O2to generate O2for relieving hypoxia inside the tumor but also transfers electrons to O2to produce superoxide radicals to kill tumor cells. Meanwhile, PmMn/SAE is able to trigger Fenton‐like reactions to generate highly toxic hydroxyl radicals to induce cancer cell apoptosis. The POD‐like catalytic mechanism of mMn/SAE is revealed using experimental results and density functional theory. Furthermor, PmMn/SAE shows good photothermal conversion efficiency (η = 22.1%) in the second near‐infrared region (1064 nm). Both the in vitro and in vivo experimental results indicate that PmMn/SAE can effectively kill cancer cells through photothermal‐enhanced catalytic therapy.
Scintillator of Polycrystalline Perovskites for High‐Sensitivity Detection of Charged‐Particle Radiations
Authors: Hunyadi Mátyás , Samu Gergely Ferenc , Csige Lóránt , Csík Attila , Buga Csaba , Janáky Csaba
Published: September 2022

Herein, the first study on the scintillation properties of CsCu2X3 and Cs3Cu2X5 (where X: Cl−, Br−, I−) is presented, describing their charged particle‐induced luminescence involving electrons, protons, α‐particles, and heavy ions, as well as revealing their capabilities on the timing and spectroscopic evaluation of single‐particle events. The thin layers are prepared with a simple and cost‐effective deposition procedure, without the incorporation of external dopants, exploiting the intrinsic radiative recombination observed in low‐dimensional perovskites. The combined effect of the high binding energy and localized stability of self‐trapped excitons, large Stokes shift, defect tolerance, and the high excitation density along the particle track leads to the emergence of boosted scintillation pulses. The observations demonstrate the first use of inorganic thin‐film scintillators with optical pulse characteristics and light yield competitive with doped single crystal scintillators, while also providing improved structural and functional stability under extreme environmental conditions.
Ultrathin ZIF‐8 Membrane through Inhibited Ostwald Ripening for High‐Flux C3H6/C3H8 Separation
Authors: Wang Jianyu , Wang Yan , Liu Yutao , Wu Hong , Zhao Mingang , Ren Yanxiong , Pu Yunchuan , Li Wenping , Wang Shaoyu , Song Shuqing , Liang Xu , He Guangwei , Han You , Jiang Zhongyi
Published: September 2022

Metal–organic frameworks (MOFs) are one of the most promising membrane materials for olefin/paraffin separations. However, most of MOF membranes have a thickness over 1 µm, which greatly compromises the permeation flux. While previous studies are focused on increasing crystal nucleus density on the substrates, achieving ultrathin membrane via modulation of the crystal growth is lacking. Herein, an inhibited Ostwald ripening (IOR) strategy is proposed to fabricate ultrathin ZIF‐8 membranes, through incorporating polymer‐based inhibitors into the membrane formula to inhibit the growth process of ZIF‐8 crystals via the metal–organic coordination. The IOR process can be readily tuned by varying the functional groups, molecular weights, and concentrations of the inhibitors, enabling a facile control over the IOR degree and thus the membrane thickness. Consequently, the thickness of ZIF‐8 membranes can be dramatically reduced to 180 nm. The resulting membranes exhibit ultrahigh C3H6/C3H8 separation performance with C3H6 permeance of 386 GPU and C3H6/C3H8 separation factor of 120. It is anticipated that this straightforward and efficient IOR strategy can open a new avenue for the fabrication of ultrathin MOF membranes to tackle many critical molecular separations.
Coding Piezoelectric Metasurfaces
Authors: Li Zhaoxi , Fei Chunlong , Yang Shenghui , Hou Chenxue , Zhao Jianxin , Li Yi , Zheng Chenxi , Wu Heping , Quan Yi , Zhao Tianlong , Chen Dongdong , Li Di , Niu Gang , Ren Wei , Xiao Meng , Yang Yintang
Published: September 2022

The manipulation of acoustic waves plays an important role in a wide range of applications. Currently, acoustic wave manipulation typically relies on either acoustic metasurfaces or phased array transducers. The elements of traditional metasurfaces are usually designed with complex artificial structures and limited by the additive manufacturing capability, which are difficult to apply in MHz frequency underwater acoustic wave control. Phased array transducers, suffering from high‐cost and complex control circuits, are usually limited by the array size and the filling ratio of the control units. Coding piezoelectric metasurfaces are reported; three wave functionalities, including beam steering, beam focusing, and vortex beam focusing are demonstrated; and acoustic tweezers and ultrasound imaging are eventually realized. The information coded on the piezoelectric metasurfaces herein is frequency independent and originates from the polarization directions, pointing either up or down, of the piezoelectric materials. Such a piezoelectric metasurface is driven by a single electrode and acts as a controllable active sound source, which combines the advantages of acoustic metasurfaces and phased array transducers while keeping the devices structurally simple and compact. The coding piezoelectric metasurfaces lead to potential technological innovations in underwater acoustic wave modulation, acoustic tweezers, biomedical imaging, industrial nondestructive testing, and neural regulation.
Efficient Anisotropic Polariton Lasing Using Molecular Conformation and Orientation in Organic Microcavities
Authors: Le Roux Florian , Mischok Andreas , Bradley Donal D. C. , Gather Malte C.
Published: September 2022

Organic exciton‐photon polariton lasers are promising candidates for the efficient generation of coherent light at room temperature. While their thresholds are now comparable with those of conventional organic photon lasers, tuning of molecular conformation and orientation as a means to control fundamental properties of their emission and thus further enhance performance remains largely unexplored. Here, a two‐fold reduction in the threshold of a microcavity polariton laser based on an active layer of poly(9,9‐dioctylfluorene) (PFO) is achieved when 15% β‐phase conformation is introduced. In addtion, taking advantage of the liquid crystalline properties of PFO, a thin photoalignment layer is used to induce nematic alignment of the polymer chains. The resulting transition dipole moment orientation increases the Rabi energy, bringing the system into the ultra‐strong coupling regime and facilitating anisotropic polariton lasing with an eight‐fold reduction in absorbed threshold, down to 1.14 pJ  (0.36 µJ cm−2) for the direction parallel to the orientation, with no emission along the orthogonal direction. This represents the first demonstration of anisotropic polariton lasing in conjugated polymer microcavities and a lower threshold than current organic vertical cavity surface‐emitting photon and polariton lasers. Dipole orientation offers new opportunities for switchable, more efficient polaritonic devices, and observation of fundamental effects at low polariton numbers.
Biomimetic Super “Silicate” Phobicity and Superhydrophobicity of Ceramic Material
Authors: Song Wenjia , Major Zsuzsanna , Guo Yiqian , Karsch Stefan , Guo Hongbo , Ferenc Krausz , Fukumoto Masahiro , Dingwell Donald B.
Published: September 2022

Plants exhibit a huge variety of biologically functional surfaces with rather unique characteristics. Analysis and mimicking of the surface leaf of the lotus plant have recently been used to develop biomimetic water repellency surfaces. A functional ceramic coating with the “lotus leaf effect” is also an interesting option in aggressive environments to mitigate corrosion by natural silicate melts. Here, inspired by natural superhydrophobic surfaces, and through the application of femtosecond laser pulses, a ceramic surface is fabricated with a hierarchical nano/microstructure. This ceramic surface exhibits the combined effects of super “silicate” phobicity at high temperature and superhydrophobicity at room temperature. The capability of the laser‐irradiated TBC is attributed to resist wetting by both silicate melt and water to its lotus‐leaf‐like dual‐scale microstructure, emulating in particular the existence of nanoparticles. These findings may be an important step toward next‐generation jet engines with greatly reduced vulnerability to environmental siliceous debris and mitigate lunar or Mars regolith dust sticking to the landing vehicle in the rocket engine exhaust plume and anti‐slagging in coal‐fired power plants or further industries.
Ionic Liquids for Efficient and Stable Perovskite Solar Cells
Authors: Wu Haixia , Li Zheng , Zhang Fangyong , Kang Chaoming , Li Yuelong
Published: September 2022

Organic‐inorganic hybrid metal halide perovskite materials, as an emerging semiconductor, have been successfully used in the field of solar cells and currently achieved a record efficiency of 25.7% within a decade, surpassing the mature thin film photovoltaic technologies on the market. To further improve the stability and efficiency of the forthcoming commercialization of perovskite solar cells (PSCs), ionic liquids (IL) have been selectively applied to the field of PSCs due to its excellent properties including designability, thermal stability, and conductivity. In this review, by summarizing recent research progress, the mechanism is discussed as IL serve as precursor solvents, additives, interfacial modification layers, independent electron transport layers, and p‐type dopants. Finally, the future research trend of IL has been prospected.
Deep‐Ultraviolet LEDs Incorporated with SiO2‐Based Microcavities Toward High‐Speed Ultraviolet Light Communication
Authors: Yu Huabin , Memon Muhammad Hunain , Jia Hongfeng , Ding Yifan , Xiao Shudan , Liu Xin , Kang Yang , Wang Danhao , Zhang Haochen , Fang Shi , Gong Chen , Xu Zhengyuan , Ooi Boon S. , Sun Haiding
Published: September 2022

Optical wireless communication (OWC) in the deep‐ultraviolet (DUV) band requires an efficient DUV light source with large bandwidth characteristics. In this work, a feasible approach is reported to enlarge the light output power as well as the bandwidth of a DUV light‐emitting diode (LED) by embedding a SiO2‐based microcavity on which an aluminum (Al) reflector is simultaneously deposited. Consequently, on the one hand, the microcavity with the Al‐reflector can facilitate photon escape from the LED to increase the light extraction efficiency, thus enhancing the light output power of the devices. On the other hand, the LED incorporated with a microcavity structure exhibits a reduced resistance–capacitance time constant, leading to an increase in the modulation bandwidth of the LED. Strikingly, the DUV LED incorporated with microcavities represents a significant enhancement of light output power by nearly 30% at 80 mA while exhibiting a higher modulation bandwidth of 12% in comparison to the conventional LED without microcavities. Thus, the implementation of the microcavity and Al reflector on top of a classic LED can enlarge the light output power and modulation bandwidth, eventually facilitating to establish viable high‐speed OWC systems.
Double‐Network Confined Supramolecular Phosphorescence Light‐Harvesting Boosting Photocatalysis
Authors: Yu Jie , Wang Hui , Liu Yu
Published: September 2022

A double‐network phosphorescence light‐harvesting (PLH) supramolecular system is successfully fabricated based on synergistic confinement strategy. First, the bicationic vinyl bromophenyl pyridine derivative (G) is encapsulated by cucurbit[8]uril (CB[8]), inducing weak phosphorescence emission at 510 nm. Subsequently, the G/CB[8] is confined by in situ copolymerization with acrylamide, displaying enhanced phosphorescence emission, then coassembled with hyaluronic acid modified hydroxypropyl‐β‐cyclodextrin (HA‐HP‐β‐CD) to form double‐network hydrogel, further improving phosphorescence lifetime from 442 µs upto 5.17 ms. Benefitting from the confinement of double‐network of supramolecular system, the doped Eosin Y (EY) as acceptor can be photosensitized by the phosphorescence of G/CB[8] leading to delayed fluorescence emission of EY with long lifetime as 36.4 µs. As compared with EY alone, by the synergistic effect of the confined microenvironment and long lifetime photosensitizer, the PLH system is successfully applied in cross‐coupling reaction and exhibits enhanced activity, providing a new strategy for the application of phosphorescence energy transfer boosting photocatalysis.
Carbon Nanodots Assisted Surface Engineering of GaN Photoanodes for Efficient and Stable Photoelectrochemical Water Oxidation
Authors: Cha An‐Na , Burungale Vishal , Seong Chaewon , Bae Hyojung , Heo Jiwon , Rho Hokyun , Kim Sumin , Ju Jin‐Woo , Ha Jun‐Seok
Published: September 2022

The process of transferring high‐quality graphene‐based films onto the surface of the electrode is very complicated and is one of the main bottlenecks in using graphene or graphene‐based protecting layers with semiconductors that are electrochemically vulnerable in harsh pH conditions. To address this, an approach is implemented for direct deposition of carbon nanodots on the surface of GaN electrodes, instead of graphene films. Instead of isolating the GaN surface from the electrolyte, the carbon nanodots function as a catalyst, expediting charge transfer at the electrode/electrolyte interface. This fast charge‐transfer process prevents accumulation of photoholes on the GaN surface, thereby improving stability. These photoholes, formed in the presence of basic electrolytes, are considered to be the main reason for photocorrosion. The effect of the surface dispersion of the carbon nanodots on the overall performance of the electrode is also studied. A significant improvement in the photocurrent density (0.44 mA cm−2 at 1.23 V vs RHE) is obtained for the optimized sample as compared to that of the bare GaN sample (0.34 mA cm−2 at 1.23 V vs RHE). Moreover, the stability performance is also improved, with almost 87% retention of the initial current value after 3 h of chronoamperometric measurements.
One‐Step Leapfrog Locally 1D Theory with Higher‐Order Enhanced Absorption for Fine‐Details Simulation
Authors: Wu Peiyu , Chen Jie , Xie Yongjun , Jiang Haolin , Natsuki Toshiaki
Published: September 2022

Based on a higher‐order concept and one‐step leapfrog formulation, an unconditionally stable leapfrog locally 1D (LOD) perfectly matched layer (PML) is proposed to not only enhance the absorbing performance in terminating an unbounded finite‐difference time‐domain (FDTD) algorithm but also improve the computational efficiency compared with the LOD‐FDTD algorithm. Most precisely, the PML is implemented by the auxiliary differential equations method. By applying the proposed scheme to a 3D electromagnetics simulation, the proposal can utilize the unconditionally stable algorithm, one‐step leapfrog formulation, and higher‐order concept in terms of attenuating low‐frequency propagation waves, enhancing the performance, and improving the computational efficiency. Numerical examples including the magic‐T waveguide model, very large‐scale integration circuits, and the structure of metamaterials are investigated to further demonstrate the efficiency, performance, and unconditional stability. The results help conclude that the proposed scheme can attain better performance and efficiency when the time step far surpasses the Courant–Friedrichs–Lewy limit. Most importantly, by employing the one‐step leapfrog formulation in the LOD algorithm, the memory requirements and simulation duration can be reduced significantly, indicating the improvement of the algorithm compared with the published LOD schemes.
Modeling Interfacial Interaction between Gas Molecules and Semiconductor Metal Oxides: A New View Angle on Gas Sensing
Authors: Yuan Chenyi , Ma Junhao , Zou Yidong , Li Guisheng , Xu Hualong , Sysoev Victor V. , Cheng Xiaowei , Deng Yonghui
Published: September 2022

With the development of internet of things and artificial intelligence electronics, metal oxide semiconductor (MOS)‐based sensing materials have attracted increasing attention from both fundamental research and practical applications. MOS materials possess intrinsic physicochemical properties, tunable compositions, and electronic structure, and are particularly suitable for integration and miniaturization in developing chemiresistive gas sensors. During sensing processes, the dynamic gas–solid interface interactions play crucial roles in improving sensors’ performance, and most studies emphasize the gas–MOS chemical reactions. Herein, from a new view angle focusing more on physical gas–solid interactions during gas sensing, basic theory overview and latest progress for the dynamic process of gas molecules including adsorption, desorption, and diffusion, are systematically summarized and elucidated. The unique electronic sensing mechanisms are also discussed from various aspects including molecular interaction models, gas diffusion mechanism, and interfacial reaction behaviors, where structure–activity relationship and diffusion behavior are overviewed in detail. Especially, the surface adsorption–desorption dynamics are discussed and evaluated, and their potential effects on sensing performance are elucidated from the gas–solid interfacial regulation perspective. Finally, the prospect for further research directions in improving gas dynamic processes in MOS gas sensors is discussed, aiming to supplement the approaches for the development of high‐performance MOS gas sensors.
Chemo‐Mechanical Energy Harvesters with Enhanced Intrinsic Electrochemical Capacitance in Carbon Nanotube Yarns
Authors: Oh Seongjae , Kim Keon Jung , Goh Byeonghwa , Park Chae‐Lin , Lee Gyu Dong , Shin Seoyoon , Lim Seungju , Kim Eun Sung , Yoon Ki Ro , Choi Changsoon , Kim Hyun , Suh Dongseok , Choi Joonmyung , Kim Shi Hyeong
Published: September 2022

Predicting and preventing disasters in difficult‐to‐access environments, such as oceans, requires self‐powered monitoring devices. Since the need to periodically charge and replace batteries is an economic and environmental concern, energy harvesting from external stimuli to supply electricity to batteries is increasingly being considered. Especially, in aqueous environments including electrolytes, coiled carbon nanotube (CNT) yarn harvesters have been reported as an emerging approach for converting mechanical energy into electrical energy driven by large and reversible capacitance changes under stretching and releasing. To realize enhanced harvesting performance, experimental and computational approaches to optimize structural homogeneity and electrochemical accessible area in CNT yarns to maximize intrinsic electrochemical capacitance (IEC) and stretch‐induced changes are presented here. Enhanced IEC further enables to decrease matching impedance for more energy efficient circuits with harvesters. In an ocean‐like environment with a frequency from 0.1 to 1 Hz, the proposed harvester demonstrates the highest volumetric power (1.6–10.45 mW cm−3) of all mechanical harvesters reported in the literature to the knowledge of the authors. Additionally, a high electrical peak power of 540 W kg−1 and energy conversion efficiency of 2.15% are obtained from torsional and tensile mechanical energy.
Kinetic Control of Ultrafast Transient Liquid Assisted Growth of Solution‐Derived YBa2Cu3O7‐x Superconducting Films
Authors: Rasi Silvia , Queraltó Albert , Banchewski Juri , Saltarelli Lavinia , Garcia Diana , Pacheco Adrià , Gupta Kapil , Kethamkuzhi Aiswarya , Soler Laia , Jareño Julia , Ricart Susagna , Farjas Jordi , Roura‐Grabulosa Pere , Mocuta Cristian , Obradors Xavier , Puig Teresa
Published: September 2022

Transient liquid assisted growth (TLAG) is an ultrafast non‐equilibrium growth process mainly governed by kinetic parameters, which are only accessible through fast in situ characterizations. In situ synchrotron X‐ray diffraction (XRD) analysis and in situ electrical resistivity measurements are used to derive kinetic diagrams of YBa2Cu3O7−x (YBCO) superconducting films prepared via TLAG and to reveal the unique peculiarities of the process. In particular, diagrams for the phase evolution and the YBCO growth rates have been built for the two TLAG routes. It is shown that TLAG transient liquids can be obtained upon the melting of two barium cuprate phases (and not just one), differentiated by their copper oxidation state. This knowledge serves as a guide to determine the processing conditions to reach high performance films at high growth rates. With proper control of these kinetic parameters, films with critical current densities of 2–2.6 MA cm−2 at 77 K and growth rates between 100–2000 nm s−1 are reached. These growth rates are 1.5–3 orders of magnitude higher than those of conventional methods.
Design Strategies for Strain‐Insensitive Wearable Healthcare Sensors and Perspective Based on the Seebeck Coefficient
Authors: Xin Yangyang , Zhou Jian , Nesser Hussein , Lubineau Gilles
Published: September 2022

Large healthcare markets have been created in highly developed economies to improve the quality of life. Wearable healthcare sensors are attracting considerable interest because of their 24 h real‐time monitoring capability, which make them useful in the detection of potential diseases. To guide the diagnosis, these sensors are designed to monitor various physical (e.g., pressure, temperature, strain, touch, bioelectricity, etc...) or chemical (e.g., glucose, oxygen, bacteria, viruses, proteins, etc...) quantities. In order to be comfortable to wear for a longer period of time, the sensors must be made with good stretchability to conformably deform with human organs. However, high stretchability always brings the problem that the measurement is very often polluted by the deformation of the substrate, making the data unreliable. According to each the sensor mechanism, multiple strain‐insensitive design strategies compatible with large deformations of the human body are discussed and the performance of these strategies are comprehensively analyzed. Then, how the intrinsic strain insensitivity of the Seebeck coefficient of nanomaterial percolation networks can define an alternative promising strategy is demostrated. Finally, the outlooks for future research and challenges in realizing strain‐insensitive sensors by applying the Seebeck effect are reported.
Computational Associative Memory with Amorphous Metal‐Oxide Channel 3D NAND‐Compatible Floating‐Gate Transistors
Authors: Sun Chen , Li Chao , Samanta Subhranu , Han Kaizhen , Zheng Zijie , Zhang Jishen , Kong Qiwen , Xu Haiwen , Zhou Zuopu , Chen Yue , Zhuo Cheng , Ni Kai , Yin Xunzhao , Gong Xiao
Published: September 2022

3D NAND has been enabling continuous NAND density and cost scaling beyond conventional 2D NAND since sub‐20‐nm nodes. However, its poly‐Si channel suffers from low mobility, instability caused by grain boundaries, and large device‐to‐device variations in electrical characteristics at highly scaled device dimensions. These drawbacks can be overcome by introducing an amorphous indium‐gallium‐zinc‐oxide (a‐IGZO) channel, which has the advantages of ultralow OFF current, back‐end‐of‐line compatibility, higher mobility than poly‐Si, and free of grain boundaries due to the amorphous nature. In this work, ultrascaled floating‐gate (FG) transistors with a channel length down to 60 nm are reported, achieving the highest ON current of 127 µA µm−1among all reporteda‐IGZO‐based flash devices for high‐density, low‐power, and high‐performance 3D NAND applications. Furthermore, a nonvolatile and area‐efficient ternary content‐addressable memory (TCAM) with only two parallel‐connecteda‐IGZO FG transistors is experimentally demonstrated to address the TCAM scalability issue. Experimentally calibrated array‐level simulations show that this design achieves at least a 240 × array‐size scalability and a 2.7‐fold reduction in search energy than TCAMs based on complementary metal‐oxide‐semiconductor technology using 16 transistors, two‐transistor‐two‐resistive random access memory, and two‐ferroelectric field‐effect‐transistor.
Stacked One‐Selector‐One‐Resistive Memory Crossbar Array With High Nonlinearity and On‐Current Density for the Neuromorphic Applications
Authors: Woo Hyo Cheon , Kim Jihun , Lee Sunwoo , Kim Hae Jin , Hwang Cheol Seong
Published: September 2022

A crossbar array using resistive switching random‐access memory requires a selector device to prevent leakage current. However, the high current flow during the electroforming and first reset process (switching from a low resistance state to a high resistance state) can degrade the selector device. Ruthenium dioxide, a conducting oxide electrode with low oxygen affinity preventing excess oxygen vacancy in a dielectric, is used as a selector electrode to acquire a TiO2‐based nonlinear selector that endures a high current flow. The selector shows high nonlinearity (≈7 × 104), high forward and reverse current ratio (≈5.5 × 102), and sufficient endurance (>107) in the one selector‐one resistive switching memory (1S1R) structure, where the HfO2 comprises the resistive switching memory. 9 × 9 crossbar array composed of the 1S1R device is used as neuromorphic hardware to classify simple characters by offline supervised learning. Further classification simulation of the rescaled Modified National Institute of Standards and Technology dataset shows 95.77% accuracy with achievable array structure.
Observation of Magnéli Phase Filament Formation in MoOx Artificial Synapse
Authors: Subin Pulickal Sasi , Antony Aldrin , Saji Kachirayil Joseph , Jayaraj Madambi Kunjukuttan Ezhuthachan
Published: September 2022

Artificial synapses are the basic building block of artificial neural networks capable of neuromorphic computing, which might overtake conventional digital computing in areas like artificial intelligence, deep learning, and in‐memory computation. Neuromorphic computing with artificial synapses opens a new window for fast in‐memory computing and image processing. In this paper, an MoOx‐based artificial synapse that mimics almost all characteristics of bio‐synapses is demonstrated. The fabricated device shows excellent synaptic properties such as potentiation, depression, forgetting, paired‐pulse facilitation, and spike‐timing‐dependent plasticity. The mechanism behind all the observed characteristics has been well explained. A lateral‐type device is also designed and tested in order to confirm the conductance change during the application of electrical pulses. Energy‐dispersive X‐ray analysis and Raman analysis reveal that the switching mechanism is primarily due to the formation and rupture of conducting filaments composed of Magnéli phases of MoOx. Since the fabricated ITO/MoOx/Ag artificial synapse exhibits excellent synaptic characteristics and the mechanism is thoroughly explored, this study will contribute to the fabrication of neural networks and future neuromorphic computing.
Charge‐Density Wave Driven Giant Thermionic‐Current Switching in 1T‐TaS2/2H‐TaSe2/2H‐MoS2 Heterostructure
Authors: Mahajan Mehak , Majumdar Kausik
Published: September 2022

1T‐TaS2 exhibits several resistivity phases due to the modulation of charge density wave (CDW). The fact that such phase transition can be driven electrically has attracted a lot of attention in the recent past toward active‐metal based electronics. However, the bias‐driven resistivity switching is not very large (less than five‐fold), and an enhancement in the same will highly impact such phase transition devices. One aspect that is often overlooked is that such phase transition is also accompanied by a significant change in the local temperature due to the low thermal conductivity of 1T‐TaS2. In this work, such electrically driven phase transition induced temperature change is exploited to promote carriers over a thermionic barrier in a 1T‐TaS2/2H‐TaSe2/2H‐MoS2 T‐Junction, achieving a 964‐fold abrupt switching in the current through the MoS2 channel. The device is highly reconfigurable and exhibits an abrupt reduction in current as well when the biasing configuration changes. The results are promising for several electronic applications, including neuromorphic chips, switching, nonlinear devices, and industrial electronics such as current and temperature sensing.
Pt Atomic Layers Boosted Hydrogen Evolution Reaction in Nonacidic Media
Authors: Guo Yan , Hou Bo , Cui Xiangzhi , Liu Xingchen , Tong Xili , Yang Nianjun
Published: September 2022

Pt‐based electrocatalysts exhibit high performance toward hydrogen evolution reaction (HER) since they can boost sluggish kinetics of water dissociation. To develop efficient Pt catalysts in nonacidic media, Pt electrocatalysts with a Rh core and a shell of a few Pt atomic layers (Rh@PtnL, n = 1, 2, 2.6) are designed. Ultrathin Pt atomic layers on a Rh core modulate electronic structures of Rh@PtnL electrocatalysts, generating a combined effect of ligand, compressive strain, and electron transfer. The Rh@PtnL electrocatalysts thus offer significantly higher HER activity in alkaline and neutral media than the RhPt alloy, Rh/C, and commercial Pt/C catalysts. The overpotential of a Rh@Pt2L electrocatalyst is only 5 mV at 10 mA cm−2 in 1.0 M KOH. The density functional theory calculations confirm that the excellent HER activity of this Rh@Pt2L electrocatalyst in nonacidic media is attributed to an enhanced hydrogen desorption and a decreased energetic barrier during the hydrogen generating process. These Rh@PtnL electrocatalysts shed the light on the design of advanced catalysts to efficiently produce green hydrogen in nonacidic media.
Creating Edge Sites within the 2D Metal‐Organic Framework Boosts Redox Kinetics in Lithium–Sulfur Batteries
Authors: Wang Xingbo , Zhao Chunrong , Liu Bingxue , Zhao Shangqian , Zhang Yongguang , Qian Lanting , Chen Zhongjun , Wang Jiantao , Wang Xin , Chen Zhongwei
Published: September 2022

Lithium–sulfur batteries have received extensive interest owing to their exceptionally high energy density. Nonetheless, their practical implementation is still impeded by the shuttle effect of polysulfides and sluggish conversion kinetics. Considering that, a porous 2D defective zeolitic imidazolate framework‐7 (ZIF‐7) with abundant active edges is rationally designed as multifunctional sulfur carriers for Li–S batteries. The 2D ZIF‐7 enables uniform distribution of sulfur and rapid Li‐ion diffusion, while rich edges facilitate sufficient exposure to active sites capturing and catalyzing polysulfides. In addition, the nitrogen defects on edge sites can further accelerate the transformation of polysulfides and decrease the energy barrier of Li2S decomposition. Consequently, the Li–S batteries demonstrate surprisingly practical prospects with a stable capacity of 676.9 mAh g−1 over 500 cycles at 1 C (capacity retention rate = 72.3%). When assembled into a pouch cell at 2.3 mg cm−2, it still exhibits a high capacity of 901.1 mAh g−1 after 100 cycles at 0.1 C. This work offers a rational structural design strategy to tackle the challenges of the sulfur cathode.
Highly Durable and Ultrafast Cycling of Dual‐Ion Batteries via In Situ Construction of Cathode–Electrolyte Interphase
Authors: Cheng Zhenjie , Guo Longfei , Dong Qingyu , Wang Chunting , Yao Qian , Gu Xin , Yang Jian , Qian Yitai
Published: September 2022

Dual‐ion batteries have shown promising prospect in energy storage, owing to their low material costs, high power capability, and environmental friendliness. However, graphite as the cathode always suffers from structural damage and electrode/electrolyte interface instability, which greatly deteriorate their electrochemical performance. Here, tris(trimethyl‐silyl) phosphite (TMSP) is added as an electrolyte additive to improve the electrochemical performance. TMSP not only scavenges the deleterious species generated by electrolytes, but also produces a thin and uniform cathode–electrolyte interphase layer on graphite. Hence, the electrochemical performance is greatly promoted. In graphite||graphite, the capacity retention is ≈96.8% at 30 °C or 92.5% after 3000 cycles in the presence of TMSP, much better than those without TMSP (62% at 30 °C or 27% after 200 cycles).
Solvent Engineering Approach Toward Optimized Phase and Morphology of CsPbBr3 Films for Efficient and Stable Planar Perovskite Solar Cells and Photodetectors
Authors: Xu Kaiyuan , Zhou Long , Chen Xi , Zhang Siyu , Guo Xing , Shou Chunhui , Lin Zhenhua , Zhang Jincheng , Chang Jingjing , Hao Yue
Published: September 2022

All‐inorganic perovskite CsPbBr3 has drawn a lot of interest as an active layer applied in photovoltaics due to its outstanding stability in ambient air. However, the procedure of preparing high‐quality CsPbBr3 films still remains a serious challenge because of the tedious process and toxic solvent. Herein, a solvent engineering method that involves green solvent with mixed H2O/C2H5OH to dissolve CsBr is presented to produce all‐inorganic perovskite CsPbBr3 films. CsPbBr3 perovskite solar cells (PSCs) are fabricated based on planar n‐i‐p structure. Compared with CsBr H2O solution, the CsPbBr3 films with optimized mixed solvent method exhibit larger grain size and improved crystallinity. As a result, the carbon‐electrode PSCs based on the mixed solvent method exhibit an increased efficiency of 9.70%. The best‐performing device retains 96.95% of the initial power conversion efficiency (PCE) after storing 1000 h under ambient air and 86.46% of the initial PCE after continuous illumination for 100 min. Moreover, the photodetector based on the same structure as the CsPbBr3 device shows high responsivity and high detectivity. The result not only provides an easy and straightforward method to prepare the uniform and pinhole‐free CsPbBr3 films, but also reduces the toxicity of the CsBr solution used to make the CsPbBr3 PSCs.
Direct Observation of “Elongated” Conformational States in α‐Synuclein upon Liquid‐Liquid Phase Separation
Authors: Ubbiali Daniele , Fratini Marta , Piersimoni Lolita , Ihling Christian H. , Kipping Marc , Heilmann Ingo , Iacobucci Claudio , Sinz Andrea
Published: September 2022

α‐Synuclein (α‐syn) is an intrinsically disordered protein (IDP) that undergoes liquid‐liquid phase separation (LLPS), fibrillation, and forms insoluble intracellular Lewy bodies in neurons, which are the hallmark of Parkinson's Disease (PD). Neurotoxicity precedes the formation of aggregates and might be related to α‐syn LLPS. The molecular mechanisms underlying the early stages of LLPS are still elusive. To obtain structural insights into α‐syn upon LLPS, we take advantage of cross‐linking/mass spectrometry (XL–MS) and introduce an innovative approach, termed COMPASS (COMPetitive PAiring StatisticS). In this work, we show that the conformational ensemble of α‐syn shifts from a “hairpin‐like” structure towards more “elongated” conformational states upon LLPS. We obtain insights into the critical initial stages of LLPS and establish a novel mass spectrometry‐based approach that will aid to solve open questions in LLPS structural biology.
Comprehensive Fragment Screening of the SARS‐CoV‐2 Proteome Explores Novel Chemical Space for Drug Development
Authors: Berg Hannes , Wirtz Martin Maria A. , Altincekic Nadide , Alshamleh Islam , Kaur Bains Jasleen , Blechar Julius , Ceylan Betül , de Jesus Vanessa , Dhamotharan Karthikeyan , Fuks Christin , Gande Santosh L. , Hargittay Bruno , Hohmann Katharina F. , Hutchison Marie T. , Marianne Korn Sophie , Krishnathas Robin , Kutz Felicitas , Linhard Verena , Matzel Tobias , Meiser Nathalie , Niesteruk Anna , Pyper Dennis J. , Schulte Linda , Trucks Sven , Azzaoui Kamal , Blommers Marcel J. J. , Gadiya Yojana , Karki Reagon , Zaliani Andrea , Gribbon Philip , da Silva Almeida Marcius , Dinis Anobom Cristiane , Bula Anna L. , Bütikofer Matthias , Putinhon Caruso Ícaro , Caterina Felli Isabella , Da Poian Andrea T. , Cardoso de Amorim Gisele , Fourkiotis Nikolaos K. , Gallo Angelo , Ghosh Dhiman , Gomes‐Neto Francisco , Gorbatyuk Oksana , Hao Bing , Kurauskas Vilius , Lecoq Lauriane , Li Yunfeng , Cunha Mebus‐Antunes Nathane , Mompeán Miguel , Cristtina Neves‐Martins Thais , Ninot‐Pedrosa Martí , Pinheiro Anderson S. , Pontoriero Letizia , Pustovalova Yulia , Riek Roland , Robertson Angus J. , Jose Abi Saad Marie , Treviño Miguel Á. , Tsika Aikaterini C. , Almeida Fabio C. L. , Bax Ad , Henzler‐Wildman Katherine , Hoch Jeffrey C. , Jaudzems Kristaps , Laurents Douglas V. , Orts Julien , Pierattelli Roberta , Spyroulias Georgios A. , Duchardt‐Ferner Elke , Ferner Jan , Fürtig Boris , Hengesbach Martin , Löhr Frank , Qureshi Nusrat , Richter Christian , Saxena Krishna , Schlundt Andreas , Sreeramulu Sridhar , Wacker Anna , Weigand Julia E. , Wirmer‐Bartoschek Julia , Wöhnert Jens , Schwalbe Harald
Published: September 2022

SARS‐CoV‐2 (SCoV2) and its variants of concern pose serious challenges to the public health. The variants increased challenges to vaccines, thus necessitating for development of new intervention strategies including anti‐virals. Within the international Covid19‐NMR consortium, we have identified binders targeting the RNA genome of SCoV2. We established protocols for the production and NMR characterization of more than 80 % of all SCoV2 proteins. Here, we performed an NMR screening using a fragment library for binding to 25 SCoV2 proteins and identified hits also against previously unexplored SCoV2 proteins. Computational mapping was used to predict binding sites and identify functional moieties (chemotypes) of the ligands occupying these pockets. Striking consensus was observed between NMR‐detected binding sites of the main protease and the computational procedure. Our investigation provides novel structural and chemical space for structure‐based drug design against the SCoV2 proteome.
Rational Design of Surface‐Enhanced Raman Scattering Substrate for Highly Reproducible Analysis
Authors: Shi Lu , Zhang Limin , Tian Yang
Published: September 2022

Surface‐enhanced Raman scattering (SERS) is an intense ongoing hot topic due to the ultrahigh sensitivity of intrinsic molecular fingerprint information. However, the reliable SERS analysis is restricted because of the lack of efficient control over the large scale of Raman substrates. With the evolution of nanotechnology, new approaches are being developed to produce substrates with higher reproducibility. In this review, we briefly introduce the factors that affect the reproducibility for SERS analysis. The recent progress in the design of SERS‐active substrates is further summarized, including fabrication of uniform nanostructures, accurate control of nanogaps and molecular regulation. In the end, an outlook of the direction of reliable SERS detection is given.
Pathology or expected morphology? Investigating patterns of cortical porosity and trabecularization during infancy and early childhood
Authors: Welsh Hayley , Brickley Megan B.
Published: September 2022

Increased cortical porosity is associated with a heightened risk of skeletal fragility due to bone loss and structural decay in adults. However, few studies have examined the etiology of cortical porosity in infants and children. This study examines whether age‐related changes in femoral growth and locomotor development influence femoral midshaft cortical porosity in a sample of 48 individuals (fetal to 3.99 years) from the 10th–13th century cemetery of St. Étienne de Toulouse, France. Histological sections were prepared and imaged using light microscopy. Midshaft geometric variables such as total area, cortical area, and pore area were calculated using BoneJ. Increased porosity and cortical trabecularization were found to be significantly associated with age, being almost exclusively present in individuals aged 0.5–1.99 years. At approximately 6 months of age infants typically begin engaging in regular femoral loading and experience an acceleration in growth. The observed increase in midshaft porosity and trabecularization, therefore, likely results from the reorganization and redistribution of cortical bone, stimulated by increased growth velocity and the onset of weight‐bearing activities. The reduction in cortical porosity and trabecularization in individuals aged 2.0–3.99 years indicates that children are approaching some sort of homeostasis as growth velocity slows and their femora adapt to consistent loading. Understanding what expected skeletal development looks like is necessary when conducting bioarcheological studies and this study provides evidence for a pattern of transient midshaft porosity during infancy and early childhood.