bluuebunny/crossref_metadata_2025_split huggingface dataset:
Defects and Disorder in Covalent Organic Frameworks for Advanced Applications
Authors: Daliran Saba , Blanco Matías , Dhakshinamoorthy Amarajothi , Oveisi Ali Reza , Alemán José , García Hermenegildo 
Published: December 2023

AbstractCrystalline porous organic polymers (CPPs) or covalent organic frameworks (COFs), are composed by light elements linked by covalent bonds. Despite the remarkable progress attained, there are still bottlenecks limiting further development, some of them related to the presence of defects during their synthesis as well as in‐depth understanding of structure of active centers and/or details of the reaction mechanism. Indeed, very often the proposed structures are far from reality because defects and disorders have not been considered. The present review provides an illustrative overview of “defects and disorder in COFs”. These defects include those not only generated during the synthesis and manipulation of COFs, but also lack of crystallinity, stacking disorder and network vacancies. The review starts giving general remarks on organic COFs and their synthetic methods, followed by different methods to play and manage defects, how to minimize them or how to take advantage of them to gain new properties and applications. Selected characterization techniques to quantify defective structures and active sites in COFs are also presented. Finally, the challenges and future opportunities in the field have been summarized in the last section.
Enhancing the Photocatalytic Activity via Direct Covalent Functionalization in Single‐Walled Carbon Nanotubes
Authors: Nova‐Fernández José Luis , González‐Muñoz Daniel , Pascual‐Coca Gustavo , Cattelan Mattia , Agnoli Stefano , Pérez‐Ruiz Raúl , Alemán José , Cabrera Silvia , Blanco Matías 
Published: December 2023

AbstractHerein, the direct covalent functionalization of single‐walled carbon nanotubes (SWNT) is presented with an amino‐decorated phenyl‐phenothiazine (PTH‐NH2) organophotocatalyst through the diazonium chemistry protocol. Three different SWNT‐PTH hybrids are prepared by varying the amount of PTH‐NH2 and diazonium agent and are fully characterized. These hybrids differ not only in the degree of functionalization, but also in the chemical structure and the photophysical properties. The study shows that these features affect the photoredox activity of the materials in the photo‐debromination of aromatic halides. Thus, sample SWNT‐PTH‐5, a functionalized nanotube with a 5% wt loading of PTH, surpasses the catalytic performance of homogeneous PTH in 11 different substrates, finishing the reaction in shorter times, in a recyclable manner and without catalyst leaching. This study demonstrates the importance of controlling the functionalization degree of SWNT with photocatalysts to prepare photocatalytic materials with even higher catalytic activity than that presented by the homogeneous PTH catalyst.
Lead‐Free (K, Na)NbO3 Piezocatalyst with Superior Piezocatalysis and Large‐Scale Production
Authors: Wang Xuzong , Wang Nan , Liao Jiayang , Wang Xin , Zou Anqi , Chen Qiang , Li Chen‐Bo‐Wen , Zhang Junwei , Wang Duan , Peng Yong , Lv Xiang , Wu Jiagang 
Published: December 2023

AbstractAlthough piezocatalysis has achieved preliminary achievements in environmental remediation and biomedical applications, large‐scale fabrication of piezocatalysts with high degradation efficiency and low cost remains challenging. In this work, a new and easy strategy to solve this challenge is innovatively proposed, that is, ceramic‐powder‐driven boosted polarization intensity, and validated the strategy is by examining potassium sodium niobate ((K, Na)NbO3, KNN) ferroelectric. KNN‐3 piezocatalyst, obtained by grinding as‐sintered ceramics into powder, shows a degradation rate (k) as high as 148 × 10−3 min−1 for rhodamine B (RhB) dye and for 31 × 10−3 min−1 for methyl orange (MO) dye, ≈18 times and 66 times than those of previously reported KNN piezocatalysts. The superior piezocatalytic activity is attributed to enhanced polarization intensity, increased oxygen vacancies, and higher charge carrier concentrations. Besides, the KNN‐3 piezocatalyst shows excellent inhibitory effects on Staphylococcus aureus and Escherichia coli strains. Therefore, the proven ceramic preparation technology enables the new strategy to mass produce high‐performance KNN piezocatalysts that hold promise for applications in dye degradation and biomedicine.
Nano/Micromotor‐Driven SERS for Highly Sensitive and Spatially Controlled Sensing
Authors: Becerril‐Castro I. Brian , Salgueiriño Veronica , Correa‐Duarte Miguel A. , Alvarez‐Puebla Ramon A. 
Published: December 2023

AbstractNano/micromotors (NMs) are tiny structures capable of converting various forms of energy into mechanical motion at the micro and nanoscale. These motors operate in environments characterized by low inertia and low Reynolds numbers. The potential applications of NMs are vast, particularly in the fields of biomedicine and environmental science. One of the most intriguing developments in this field is the integration of NMs with surface‐enhanced Raman scattering (SERS) spectroscopy. SERS is a powerful analytical technique that enhances the Raman intensity of molecules, allowing for highly sensitive detection and analysis of trace amounts of substances. This integration offers highly precise and localized ultrasensing capabilities. The combination of NMs with SERS can also facilitate real‐time imaging inside living organisms. This has immense potential in chemical and cell biology and medical diagnostics and prognosis. Herein this review describes the types of NMs and their fabrication, the incorporation of plasmonic nanostructures, capable of creating strong electromagnetic fields when illuminated by light, which in turn enhances the Raman signals significantly, their applications, and their future prospects in areas such as precision medicine, environmental monitoring, and possibly even in new realms like microscale robotics and targeted therapeutics.
Way to a Library of Ti‐Series Oxide Nanofiber Sponges that are Highly Stretchable, Compressible, and Bendable
Authors: Cheng Xiaota , Chang Xinyi , Zhang Xinxin , Dai Jin , Fong Hao , Yu Jianyong , Liu Yi‐Tao , Ding Bin 
Published: December 2023

AbstractTi‐series oxide ceramics in the form of aerogels, such as TiO2, SrTiO3, BaTiO3, and CaCu3Ti4O12, hold tremendous potential as functional materials owing to their excellent optical, dielectric, and catalytic properties. Unfortunately, these inorganic aerogels are usually brittle and prone to pulverization owing to weak inter‐particulate interactions, resulting in restricted application performance and serious health risks. Herein, a novel strategy is reported to synthesize an elastic form of an aerogel‐like, highly porous structure, in which activity‐switchable Ti‐series oxide sols transform from the metastable state to the active state during electrospinning, resulting in condensation and solidification at the whipping stage to obtain curled nanofibers. These curled nanofibers are further entangled when flying in the air to form a physically interlocked, elastic network mimicking the microstructure of high‐elasticity hydrogels. This strategy provides a library of Ti‐series oxide nanofiber sponges with unprecedented stretchability, compressibility, and bendability, possessing extensive opportunities for greener, safer, and broader applications as integrated or wearable functional devices. As a proof‐of‐concept demonstration, a new, elastic form of TiO2, composed of both “white” and “black” TiO2 nanofiber sponges, is constructed as spontaneous air‐conditioning textiles in smart clothing, buildings, and vehicles, with unique bidirectional regulation of radiative cooling in summer and solar heating in winter.
A Synergistic Lipid Nanoparticle Encapsulating mRNA Shingles Vaccine Induces Potent Immune Responses and Protects Guinea Pigs from Viral Challenges
Authors: Cheng Xingdi , Liu Sujia , Sun Jing , Liu Lin , Ma Xinghuan , Li Jingjiao , Fan Bangda , Yang Chen , Zhao Yuanyuan , Liu Shuai , Wen Yixing , Li Wei , Sun Simin , Mi Shiwei , Huo Haonan , Miao Lei , Pan Hao , Cui Xiaolan , Lin Jiaqi , Lu Xueguang 
Published: December 2023

AbstractShingles is caused by the reactivation of varicella zoster virus (VZV) and manifests as painful skin rashes. While the recombinant protein‐based vaccine proves highly effective, it encounters supply chain challenges due to a shortage of the necessary adjuvant. Messenger RNA (mRNA)‐based vaccines can be rapidly produced on a large scale, but their effectiveness relies on efficient delivery and sequence design. Here, an mRNA‐based VZV vaccine using a synergistic lipid nanoparticle (Syn‐LNP) containing two different ionizable lipids is developed. Syn‐LNP shows superior mRNA expression compared to LNPs formulated with either type of ionizable lipid and to a commercialized LNP. After encapsulating VZV glycoprotein E (gE)‐encoding mRNA, mgE@Syn‐LNP induces robust humoral and cellular immune responses in two strains of mice. The magnitude of these responses is similar to that induced by adjuvanted recombinant gE proteins and significantly higher than that observed with live‐attenuated VZV. mgE@Syn‐LNP exhibits durable humoral responses for over 7 months without obvious adverse effects. In addition, mgE@Syn‐LNP protects vaccinated guinea pigs against live VZV challenges. Preliminary studies on the mRNA antigen design reveal that the removal of glycosylation sites of gE greatly reduces its immune responses. Collectively, Syn‐LNP encapsulating gE‐encoded mRNA holds great promise as a shingles vaccine.
Important Role of Ion Flux Regulated by Separators in Lithium Metal Batteries
Authors: Jia Hao , Zeng Chao , Lim Hyung‐Seok , Simmons Ashley , Zhang Yuepeng , Weber Marc H. , Engelhard Mark H. , Gao Peiyuan , Niu Chaojiang , Xu Zhijie , Zhang Ji‐Guang , Xu Wu 
Published: December 2023

AbstractPolyolefin separators are the most common separators used in rechargeable lithium (Li)‐ion batteries. However, the influence of different polyolefin separators on the performance of Li metal batteries (LMBs) has not been well studied. By performing particle injection simulations on the reconstructed three‐dimensional pores of different polyethylene separators, it is revealed that the pore structure of the separator has a significant impact on the ion flux distribution, the Li deposition behavior, and consequently, the cycle life of LMBs. It is also discovered that the homogeneity factor of Li‐ion toward Li metal electrode is positively correlated to the longevity and reproducibility of LMBs. This work not only emphasizes the importance of the pore structure of polyolefin separators but also provides an economic and effective method to screen favorable separators for LMBs.
Design of a Novel Drug Delivery Nanosystem that Simultaneously Realizes Real‐Time Tracing and Drug Delivery Across the Blood–Brain Barrier
Authors: Wang Xiu , Qin Lijing , Song Baoqin , Wu Mengru , Liang Wanjun 
Published: December 2023

AbstractAcute encephalitis is a brain infection that can harm the nervous system if not recognized and treated promptly. However, the presence of the blood–brain barrier restricts therapeutic agent distribution from the bloodstream to the brain parenchyma, severely restricting effective therapy for this disease. Herein, a novel drug delivery system based on a macrophage (RAW 264.7 cells) artifactual diagnostic and therapeutic nanoparticles (IPD@RAW) drug‐loading approach is presented, which exploits RAW cells' ability to cross the blood–brain barrier and go toward inflammation, and efficiently realizes the targeted enrichment of diagnostic and therapeutic nanoparticles at the site of inflammation in the brain. This nano‐drug‐carrying technology can accurately depict the degree of inflammation in real time for an extended period due to the significant penetration depth and high signal‐to‐noise ratio of near‐infrared (NIR) imaging. Meanwhile, the modified polydopamine can trigger the controlled release of anti‐inflammatory drugs through photothermal conversion under NIR irradiation to reduce the expression of cellular inflammatory factors, such as TNF‐α, IL‐6, and IL‐1β, and alleviate the brain damage due to secretion of this inflammatory factor. As a result, this drug delivery system provides a reliable tool for overcoming the blood–brain barrier to achieve early diagnosis and treatment of acute encephalitis.
Manufacture of Biomimetic Auricular Surgical Implants Using 3D Printed High Density Polyethylene Microfibers
Authors: Paxton Naomi C , Luposchainsky Simon , Reizabal Ander , Saiz Paula G , Bade Stuart , Woodruff Maria A , Dalton Paul D 
Published: December 2023

AbstractThis study demonstrates a new approach to manufacturing biomimetic auricular surgical implants using melt electrowriting (MEW) technology to fabricate microfiber high‐density polyethylene (HDPE) scaffolds. An emerging filament‐driven printhead and MEW printer, termed the “MEWron”, is used to enable precise control over the material extrusion process and fiber formation. By predicting the optimal extrusion conditions, continuous and uninterrupted fiber production is achieved, enabling further optimization of filament‐driven MEW fibers with a diameter of 60.5 ± 2.6 µm. As a case study, an application of microfiber HDPE fabrication is selected that comprised the design and fabrication of personalized auricular (ear) surgical implants, specifically tailored to match the unique morphology of individual patients. Patient‐specific implant models matched to the natural shape and structure of the human ear are successfully fabricated. Furthermore, the manufactured implants exhibit excellent mechanical properties, offering a 13‐fold increase in tensile stiffness compared to MEW PCL scaffolds. Overall, this research demonstrates the feasibility and potential of MEW‐based HDPE implants as a promising alternative to traditional auricular reconstruction methods, offering an alternative avenue for improved patient outcomes and enhanced aesthetic results.
Asymmetric Silicon Dimers Made by Single‐Shot Laser‐Induced Transfer Demultiplex Light of Different Wavelengths
Authors: Obydennov Dmitry V. , Shilkin Daniil A. , Gulkin Dmitry N. , Lyubin Evgeny V. , Zhigunov Denis M. , Bessonov Vladimir O. , Fedyanin Andrey A. 
Published: December 2023

AbstractNanofabrication technologies significantly influence the development of modern optical science. One of such technologies is laser‐induced transfer, which allows the creation of single Mie‐resonant spherical particles on a wide range of substrates. This study shows that this method can provide asymmetric dimers at the output: a single femtosecond pulse being focused on a silicon‐on‐insulator wafer results in appearing two nearly spherical particles of different sizes. The resulting dimers are characterized by scanning electron microscopy, elastic light scattering and Raman spectroscopy to gain insight into their structural properties. Back focal plane imaging and variable‐color evanescent‐wave illumination are then employed to measure the light scattering patterns from isolated dimers. Due to the interference of the excited resonances, the observed patterns are strongly asymmetric in a range of visible wavelengths, which is consistent with theoretical predictions. The results demonstrate the potential of asymmetric silicon dimers made by single‐shot laser‐induced transfer for color routing at visible light.
Semiconductor THz Emitting Nanometasurface (STEN)
Authors: Wang Kemeng , Gu Yangfan , Lu Yongchang , Gu Jianqiang , Singh Ranjan , Zhang Weili 
Published: December 2023

AbstractThe direct bandgap semiconductor serves as a fundamental terahertz (THz) source, generating terahertz waves through ultrafast femtosecond light excitation. While the direct bandgap semiconductor THz source does not rely on an external bias voltage, its limited radiation power poses a challenge to its implementation in compact THz systems. Here, nanometasurfaces etched on a semi‐insulating gallium arsenide (GaAs) substrate for enhanced THz emission are reported. The proposed semiconductor terahertz emitting nanometasurface (STEN) device based on GaAs direct bandgap semiconductor shows a 35‐fold increase in THz power and enables precise control of the emitted bandwidth. Giant emission is attributed to the enhanced absorption of pump light by the GaAs nano‐pillar array and the localized effect of the pump field. Experimental results confirm the effectiveness of the structures, demonstrating a negative correlation between the radiation power enhancement factor and pump power, indicating suitability for low‐power sources. This design offers broad prospects for semiconductor THz emitting nanometasurfaces, ideal for integration with compact femtosecond lasers.
Tunable Far‐Infrared Polarization Imaging Based on VO2 Metasurfaces
Authors: Ma Junwei , Kang Tongtong , Ke Zungui , Yao Mengqi , Ma Xiaoshao , Luo Qing , Bi Lei , Qin Jun 
Published: December 2023

AbstractPolarization imaging enables the capture of material properties and surface characteristics of objects, finding applications in remote sensing and defense. However, most existing polarization imaging systems rely on polarization filtering elements, resulting in energy loss exceeding 50% and compromising intensity imaging performance. Conventionally, a rotary device equipped with different polarizers and a blank area is used to acquire both polarization and intensity images, which is cumbersome for integration and miniaturization purposes. In this study, a miniaturized and easily integrated active metasurface based on VO2 grating structure for switchable detection of intensity and polarization in the far‐infrared band (8–14 µm) is proposed. With VO2 in the dielectric state, the device exhibits high transmittance for both TE‐ and TM‐polarized light (Experimental transmittance of up to 65%). Upon phase transition to the metallic state, the device demonstrates low transmittance for TE‐polarized light while maintaining high transmittance for TM‐polarized light (linear polarization extinction ratio up to 10 dB). Finally, the tunable thermal intensity and polarization imaging capabilities of the custom‐made setup are characterized. The metasurface showcases comparable performance to standard commercial polarizers in terms of polarization imaging. The developed tunable far‐infrared polarization imaging system holds promise for next‐generation multidimensional information perception.
Nonlinear Optical Response Modulated by Lattice Reconstruction in Small‐Angle Twisted Bilayer MoS2
Authors: Xu Chang , Mao Yu , Li Kaihui , Wang Zixin , Liu Xueying , Dong Ningning , Li Si‐Yu , Pan Anlian , Wang Jun 
Published: December 2023

AbstractSubtle perturbations in interlayer twist angles offer a novel investigational avenue for revealing intriguing optical characteristics within the domain of 2D materials. In this study, a homogeneous bilayer structure featuring precisely defined interlayer twist angles is meticulously engineered by stacking monolayer single‐crystal MoS2 in a controlled, layer‐by‐layer manner. Scanning tunneling microscopy (STM) reveals an unexpected lattice reconstruction, particularly at twist angles of ≤ 2°, which induces the emergence of expansive rhombohedral‐stacked large triangular domains. Furthermore, a second‐harmonic generation (SHG) is utilized as a sensitive modality to demonstrate profound transformations in the local electron band structures. By combining the linear spectra with SHG, the change in the C‐exciton optical response in the band‐nesting region of the small‐angle twisted bilayer MoS2 before and after crossing a critical twist angle of 2° is discussed. The study shows that SHG can be used as a nondestructive method to characterize the lattice structure of small‐angle twisted bilayer samples. Furthermore, determining the potential relationship between the lattice reconstruction and the linear and nonlinear spectra further demonstrates the regulatory effect of the interlayer twist angle on the nonlinear optical effects of 2D materials.
Organic–Inorganic Hybrid Mn‐Based Transparent Glass for Curved X‐Ray Scintillation Imaging
Authors: Zhang Zhi‐Zhong , He Zi‐Lin , Luo Jian‐Bin , Wei Jun‐Hua , Guo Xiu‐Xian , Chen Jing‐Hua , Kuang Dai‐Bin 
Published: December 2023

AbstractThe current mainstream planar X‐ray imaging techniques face significant challenges for accurately capturing the internal structure of curved objects, since the variable distances between the curved objects and the flat‐panel scintillation screen cannot eliminate the distortion in X‐ray imaging. Though large‐area and transparent curved scintillation screens are much more desirable. Here, organic–inorganic hybrid Mn‐based single crystals ([CH3Ph3P]2MnX4, X = Cl, Br, I) exhibiting high photoluminescence quantum yield (PLQY) and low melting temperature have been employed to prepare transparent glass for X‐ray scintillation imaging application through a low‐temperature melting strategy. The [CH3Ph3P]2MnBr4‐glass shows high PLQY (47.8%), high‐resolution X‐ray imaging performance (12.3 lp mm−1), low limit of detection (25.33 nGy s−1), and impressive X‐ray irradiation stability (102 Gy). Furthermore, high‐contrast X‐ray imaging at a low dose (6.865 µGy per exposure, 14.5 times lower than the chest radiograph) is achieved. Based on the low glass transition temperature (Tg = 53.6 °C) and easy‐shapeable properties of [CH3Ph3P]2MnBr4‐glass scintillator, the large‐area curved scintillation screen with a series of sizes of Φ 2×4 – Φ 8×4 cm2 can be easily fabricated and show high X‐ray imaging quality. These findings provide a paradigm for future research in shapeable X‐ray scintillators, unlocking new possibilities for curved and 3D X‐ray imaging.
Simple Non‐Destructive and 3D Multi‐Layer Visual Hull Reconstruction with an Ultrabroadband Carbon Nanotubes Photo‐Imager
Authors: Li Kou , Kinoshita Yuya , Shikichi Daiki , Kubota Miki , Takahashi Norika , Zhang Qi , Koshimizu Ryo , Tadenuma Reiji , Yamamoto Minami , Takai Leo , Zhou Zhenyu , Sato Imari , Kawano Yukio 
Published: December 2023

AbstractWhile millimeter‐wave (MMW)–infrared (IR) broad photo‐imaging exhibits significant potential as an inspection technique, photo‐thermoelectric (PTE) detector operations employing carbon nanotubes (CNTs) are highly suitable because of their efficient absorption characteristics in the above bands. Such an imaging device design and the associated material coordination allow the aggregation of multiple wavelength‐specific optical information for the constituent identification of target objects in a non‐destructive manner with high sensitivity. On the other side, computer vision techniques facilitate 3D structure reconstruction as approaches from inspection methodologies, in addition to the aforementioned imaging device design. Although non‐destructive inspections require collectively satisfying both constituent identification and structural reconstruction, investigations combining MMW–IR broad photo imaging and computer vision monitoring are still insufficient. This work demonstrates computer vision‐driven simple 3D composite multi‐layer reconstructions via non‐destructive broadband multiple‐wavelength monitoring with the CNT film PTE imager. Visual hull evaluation, which is one of the representative computer vision techniques, converts 2D transmissive PTE images with different viewpoints into 3D reconstruction models. The subsequential graphical superposition of these wavelength‐specific models results in non‐destructive entire reconstructions of 3D composite multi‐layer target objects. Therefore, the present computer vision‐driven PTE broadband 3D reconstruction bridges the gap between methodologies and device design strategies toward non‐destructive inspection applications.