bluuebunny/crossref_metadata_2025_split huggingface dataset:
On‐Demand Editing of Surface Properties of Microstructures Made by 3D Direct Laser Writing via Photo‐Mediated RAFT Polymerization
Authors: Wu Xingyu , Gross Bryan , Leuschel Benjamin , Mougin Karine , Dominici Sébastien , Gree Simon , Belqat Mehdi , Tkachenko Vitalii , Cabannes‐Boué Benjamin , Chemtob Abraham , Poly Julien , Spangenberg Arnaud 
Published: December 2021

AbstractRecently, photo‐controlled reversible addition‐fragmentation chain transfer (RAFT) polymerization has been successfully applied in digital light processing 3D printing. It provides a convenient way to tune the surface properties of the 3D printed object. However, so far, 3D micro‐ and nanostructures and reconfigurations based on photo‐induced RAFT polymerization have not been presented. In this work, one macro‐photoiniferter, synthesized by photo‐controlled RAFT polymerization is applied, to 3D direct laser writing. Thanks to the exquisite spatial control of the photoreaction, 3D microstructures with feature sizes of around 500 nm are successfully obtained. Taking advantage of the presence of dormant polymeric RAFT agents, photo‐induced post‐modification of the printed microstructures is highlighted via the elaboration of multi‐chemistry patterns including thermo‐responsive ones. These results open new perspectives in multi‐material and 4D micro‐printing.
Quasi‐Single Crystalline Cuprous Oxide Wafers via Stress‐Assisted Thermal Oxidation for Optoelectronic Devices
Authors: Xiao Meng , Gui Pengbin , Dong Kailian , Xiong Liangbin , Liang Jiwei , Yao Fang , Li Wenjing , Liu Yongjie , Li Jiashuai , Ke Weijun , Tao Chen , Fang Guojia 
Published: December 2021

AbstractP‐type semiconductor cuprous oxide (Cu2O) offers promising optoelectronic applications such as solar cells and photodetectors owing to its considerable absorption coefficients and high carrier mobility. However, polycrystalline Cu2O films with low carrier mobility resulting from excessive grain boundaries and structure disorder fail to meet the demands for these optoelectronic applications. Here a stress‐assisted thermal oxidation method to fabricate p‐type <110>‐textured quasi‐single crystalline Cu2O (c‐Cu2O) wafers with centimeter‐scale grains is developed. It is found that strain energy induced by thermal contact stress plays a critical role in crystal growth. The resultant <110>‐textured quasi‐single c‐Cu2O wafers exhibit excellent crystallinity with rocking curve having a low full width at half maximum of 0.022°, a low defect density of 2 × 1011 cm−3, a high mobility exceeding 100 cm2 V−1 s−1, and a long minority lifetime of 98.5 µs. Such quasi‐single c‐Cu2O wafers lead to efficient solar cells with an open‐circuit voltage of 0.95 V and highly responsive photodetectors with superior cycling stability. These results indicate not only the advancement of fabricating high‐quality Cu2O wafers upon controllable methodology but also the promising optoelectronic applications using p‐type metal oxide semiconductors.
Hofmeister Effect and Electrostatic Interaction Enhanced Ionic Conductive Organohydrogels for Electronic Applications
Authors: Wu Yinghong , Mu Yijie , Luo Yang , Menon Carlo , Zhou Zhiwen , Chu Paul K. , Feng Shien‐Ping 
Published: December 2021

AbstractThe emerging cryoprotectant replacement method endows hydrogels with nondrying and antifreezing properties, but the low conductivity still limits wider electronic applications. In this work, the Hofmeister effect and electrostatic interaction are introduced to improve the conductivity of organohydrogels and their enhancement mechanism are studied in depth. The Hofmeister effect mainly influences the physical properties, such as the pore structure and mechanical strength, which subsequently impacts ion transfer during the solvent replacement process. The lithium and sodium bonds formed by the electrostatic interaction play a more important role in the conductivity of organohydrogels and an overall picture is presented based on the synergistic enhancement of the Hofmeister effect and electrostatic interaction to achieve highly ionic conductive organohydrogels. The champion organohydrogels are applied as soft ionic conductors and antireflective layers in triboelectric, photovoltaic, and thermoelectric applications. The proposed mechanism advances the understanding of the contribution of ions to organohydrogels for wearable electronics.
Semiconducting MOF@ZnS Heterostructures for Photocatalytic Hydrogen Peroxide Production: Heterojunction Coverage Matters
Authors: Liu Chao , Bao Tong , Yuan Ling , Zhang Chaoqi , Wang Jing , Wan Jingjing , Yu Chengzhong 
Published: December 2021

AbstractConstruction of semiconducting metal‐organic framework based heterostructures is emerging as a promising strategy for enhancing their photocatalytic performances. Here, tetrapod‐like NH2‐MIL‐125@ZnS heterostructures with tunable heterojunction coverage and well‐matched band structure are synthesized as photocatalysts. When used for photocatalytic O2 reduction reaction, a heterojunction coverage of ≈45.1% leads to the best performance with a hydrogen peroxide production rate of ≈120 mm g−1 h−1, outperforming control samples with either larger or smaller heterojunction coverages and most reported MOF based photocatalysts in similar reaction systems.
Hydrogel Microparticle‐Templated Anti‐Solvent Crystallization of Small‐Molecule Drugs
Authors: Bora Meghali , Hsu Myat Noe , Khan Saif A , Doyle Patrick S 
Published: December 2021

AbstractConventional formulation strategies for hydrophobic small‐molecule drug products frequently include mechanical milling to decrease active pharmaceutical ingredient (API) crystal size and subsequent granulation processes to produce an easily handled powder. A hydrogel‐templated anti‐solvent crystallization method is presented for the facile fabrication of microparticles containing dispersed nanocrystals of poorly soluble API. Direct crystallization within a porous hydrogel particle template yields core–shell structures in which the hydrogel core containing API nanocrystals is encased by a crystalline API shell. The process of controllable loading (up to 64% w/w) is demonstrated, and tailored dissolution profiles are achieved by simply altering the template particle size. API release is well described by a shrinking core model. Overall, the approach is a simple, scalable and potentially generalizable method that enables novel means of independently controlling both API crystallization and excipient characteristics, offering a “designer” drug particle system.
Achieving Efficient NIR‐II Type‐I Photosensitizers for Photodynamic/Photothermal Therapy upon Regulating Chalcogen Elements
Authors: Wen Kaikai , Tan Hui , Peng Qian , Chen Hao , Ma Han , Wang Lu , Peng Aidong , Shi Qinqin , Cai Xiaodong , Huang Hui 
Published: December 2021

AbstractSecond near‐infrared (NIR‐II) window type‐I photosensitizers have intrinsic advantages in photodynamic/photothermal therapy (PDT/PTT) of some malignant tumors with deep infiltration, large size, complicated location, and low possibility of surgery/radiotherapy. Herein, three chalcogen‐element‐based donor–acceptor‐type semiconducting polymers (poly[2,2″‐((E)‐4,4″‐bis(2‐octyldodecyl)‐[6,6″‐bithieno[3,2‐b]pyrrolylidene]‐5,5″(4H,4″H)‐dione)‐alt‐2,5‐(thiophene)] (PTS), poly[2,2″‐((E)‐4,4″‐bis(2‐octyldodecyl)‐[6,6″‐bithieno[3,2‐b]pyrrolylidene]‐5,5″(4H,4″H)‐dione)‐alt‐2,5‐(selenophene)] (PTSe), and poly[2,2″‐((E)‐4,4″‐bis(2‐octyldodecyl)‐[6,6″‐bithieno[3,2‐b]pyrrolylidene]‐5,5″(4H,4′H)‐dione)‐alt‐2,5‐(tellurophene)] (PTTe)) are synthesized and fully characterized, demonstrating strong absorption in the NIR‐II region. Upon adjusting the chalcogen elements, the intramolecular charge‐transfer characteristics and the heavy‐atom effect are tuned to enhance the intersystem crossing rate, improving the photodynamic effect. Moreover, the energy levels and Gibbs free energies are tuned to facilitate the type‐I photodynamic process. As a result, PTTe nanoparticles (NPs) produce superoxide anion radicals (O2•−) more efficiently and demonstrate higher photothermal conversion efficiency than PTS and PTSe NPs upon NIR‐II (1064 nm) laser irradiation, exhibiting unprecedented NIR‐II type‐I PDT/PTT performance in vitro and in vivo. This work provides ideas for achieving high‐performance NIR‐II type‐I PDT/PTT semiconducting polymers for hypoxic oncotherapy.
Vertical Extrusion Cryo(bio)printing for Anisotropic Tissue Manufacturing
Authors: Luo Zeyu , Tang Guosheng , Ravanbakhsh Hossein , Li Wanlu , Wang Mian , Kuang Xiao , Garciamendez‐Mijares Carlos Ezio , Lian Liming , Yi Sili , Liao Junlong , Xie Maobin , Guo Jie , Zhou Zongke , Zhang Yu Shrike 
Published: December 2021

AbstractDue to the poor mechanical properties of many hydrogel bioinks, conventional 3D extrusion bioprinting is usually conducted based on theX–Yplane, where the deposited layers are stacked in theZ‐direction with or without the support of prior layers. Herein, a technique is reported, taking advantage of a cryoprotective bioink to enable direct extrusion bioprinting in the vertical direction in the presence of cells, using a freezing plate with precise temperature control. Of interest, vertical 3D cryo‐bioprinting concurrently allows the user to create freestanding filamentous constructs containing interconnected, anisotropic microchannels featuring gradient sizes aligned in the vertical direction, also associated with enhanced mechanical performances. Skeletal myoblasts within the 3D‐cryo‐bioprinted hydrogel constructs show enhanced cell viability, spreading, and alignment, compared to the same cells in the standard hydrogel constructs. This method is further extended to a multimaterial format, finding potential applications in interface tissue engineering, such as creation of the muscle–tendon unit and the muscle–microvascular unit. The unique vertical 3D cryo‐bioprinting technique presented here suggests improvements in robustness and versatility to engineer certain tissue types especially those anisotropic in nature, and may extend broad utilities in tissue engineering, regenerative medicine, drug discovery, and personalized therapeutics.
Self‐Assembly of Strongly Amphiphilic Janus Nanoparticles into Freestanding Membranes
Authors: Mihali Voichita , Honciuc Andrei 
Published: December 2021

AbstractAmphiphilic nanoparticles can adsorb at interfaces between immiscible phases and form membranes. The ability to handle nanoparticle monolayers/bilayers as freestanding membranes independently from the interfaces on which they form can be of significant practical interest. Janus nanoparticles (JNPs) could generate membranes that have tunable pore size and are amphiphilic. Here it is shown how freestanding membranes from JNPs can be generated. First, strongly amphiphilic Janus nanoparticles that generate foams in surfactant‐free conditions are synthesized. Upon drying the foam lamellae remain as freestanding membranes consisting of perfectly oriented bilayers or monolayers of JNPs, thus providing direct evidence of structural organization of amphiphiles in foam lamellae. The wet foam lamellae can be picked up on grids and upon drying generate freestanding membranes. Sturdy freestanding membranes by transferring monolayers of JNPs from the air–water interfaces onto grids with fine openings are also prepared.
Thermal Fluctuations of the Optical Properties of Nanomechanical Photonic Metamaterials
Authors: Li Jinxiang , Papas Dimitrios , Liu Tongjun , Ou Jun‐Yu , MacDonald Kevin F. , Plum Eric , Zheludev Nikolay I. 
Published: December 2021

AbstractThe combination of optical and mechanical resonances offers strong hybrid nonlinearities, bistability, and the ability to efficiently control the optical response of nanomechanical photonic metamaterials with electric and magnetic field. While optical resonances can be characterized in routine transmission and reflection experiments, mapping the high‐frequency mechanical resonances of complex metamaterial structures is challenging. Here, it is reported that high‐frequency time‐domain fluctuations in the optical transmission and reflection spectra of nanomechanical photonic metamaterials are directly linked to thermal motion of their components and can give information on the fundamental frequencies and damping of the mechanical modes. This is demonstrated by analyzing time‐resolved fluctuations in the transmission and reflection of dielectric and plasmonic nanomembrane metamaterials at room temperature and low ambient gas pressure. These measurements reveal complex mechanical responses, understanding of which is essential for optimization of such functional photonic materials. At room temperature the magnitude of the observed metamaterial transmission and reflection fluctuations is of order 0.1% but may exceed 1% at optical resonances.
Rationalizing the Thermal Response of Dual‐Center Molecular Thermometers: The Example of an Eu/Tb Coordination Complex
Authors: Carneiro Neto Albano N. , Mamontova Ekaterina , Botas Alexandre M. P. , Brites Carlos D. S. , Ferreira Rute A. S. , Rouquette Jérôme , Guari Yannick , Larionova Joulia , Long Jérôme , Carlos Luís D. 
Published: December 2021

AbstractLuminescence thermometry allows the remote monitoring of the temperature and holds the promise to drive the next generation of future nano or micrometric devices. Materials able to sense the temperature are usually based on one or several lanthanide ions allowing a ratiometric measurement. Optimizing the thermometric features is usually achieved through a serendipity approach, but it still appears difficult to accurately predict the sensing performance. Through a combination of experiment and theoretical calculations, the first example of an energy‐driven luminescent molecular thermometer [Tb0.94Eu0.06(bpy)2(NO3)3] (bpy = 2,2′‐bipydine) displaying an exceptional thermal cyclability around room temperature is reported, for which the thermal properties could be theoretically forecasted. This work provides comprehensive guidelines that can be easily extended for any dual‐center thermometer in which energy transfer drives the thermometric performance opening the avenue for the smart engineering of sensing devices.
Tailoring Transition Dipole Moment in Colloidal Nanocrystal Thin Film on Nanocomposite Materials
Authors: Lee Kwang Jin , Kim Gahyeon , Lim Joonhyung , Nah Sanghee , Jeong Kwang Seob , Cho Minhaeng 
Published: December 2021

AbstractControlling the transition dipole moment is extremely important for various photophysical characteristics in semiconductors. Especially, suppression of Auger recombination in quantum dots (QDs) is essential for the development of novel applications, including bioimaging, lasing, and optoelectronic devices. To date, most of the studies on the Auger process are conducted on the basis of manipulating the material property such as wavefunction of electron and hole, energy band, and confinement potential. However, a new way of tuning the Auger process using nanocomposite materials is not reported. In this work, the biexciton Auger recombination (BAR) process in CdSe/CdS(1 ML) nanocrystal thin‐film is successfully controlled by introducing nanocomposite materials. Performing pump intensity‐dependent transient absorption experiments, a significant reduction (up to 30%) of BAR rate is observed in the presence of nanocomposite structures. This notable suppression effect is attributed to the modulation of the net transition dipole moment. These findings will provide further insight into the rational design of QDs combining with a nanostructure that efficiently suppresses Auger recombination rates.
In‐Plane Field‐Driven Excitonic Electro‐Optic Modulation in Monolayer Semiconductor
Authors: Vella Daniele , Barbosa Marcelo B. , Trevisanutto Paolo E. , Verzhbitskiy Ivan , Zhou Justin Yong , Watanabe Kenji , Taniguchi Takashi , Kajikawa Kotaro , Eda Goki 
Published: December 2021

Abstract2D semiconductors are attractive candidates for on‐chip electro‐optic modulators due to their ease of integration and rich exciton‐mediated phenomena. While electrostatic doping and out‐of‐plane field effect have been extensively studied, in‐plane field‐induced phenomena remain largely unexplored. Here electro‐optic response of monolayer WSe2 subject to modulating in‐plane electric fields probed by electroabsorption and electroreflectance spectroscopy is reported. The devices are found to exhibit spatially varying response near exciton resonance, which cannot be explained by predicted effects such as Pockels and excitonic Stark effect. It is shown that the modulation signal is dominated by exciton linewidth broadening and narrowing associated with local accumulation and depletion of free holes. The field and frequency dependence of the devices is distinct from those of charge modulation devices. The observed behavior is ascribed to elastic scattering of excitons with field‐driven intrinsic free carriers.
Anti‐MicroRNA‐21 Oligonucleotide Loaded Spermine‐Modified Acetalated Dextran Nanoparticles for B1 Receptor‐Targeted Gene Therapy and Antiangiogenesis Therapy
Authors: Zheng Tao , Wang Wentao , Mohammadniaei Mohsen , Ashley Jon , Zhang Ming , Zhou Ninglin , Shen Jian , Sun Yi 
Published: December 2021

AbstractThe use of nanoparticles (NPs) to deliver small inhibiting microRNAs (miRNAs) has shown great promise for treating cancer. However, constructing a miRNA delivery system that targets brain cancers, such as glioblastoma multiforme (GBM), remains technically challenging due to the existence of the blood‐tumor barrier (BTB). In this work, a novel targeted antisense miRNA‐21 oligonucleotide (ATMO‐21) delivery system is developed for GBM treatment. Bradykinin ligand agonist‐decorated spermine‐modified acetalated dextran NPs (SpAcDex NPs) could temporarily open the BTB by activating G‐protein‐coupled receptors that are expressed in tumor blood vessels and tumor cells, which increase transportation to and accumulation in tumor sites. ATMO‐21 achieves high loading in the SpAcDex NPs (over 90%) and undergoes gradual controlled release with the degradation of the NPs in acidic lysosomal compartments. This allows for cell apoptosis and inhibition of the expression of vascular endothelial growth factor by downregulating hypoxia‐inducible factor (HIF‐1α) protein. An in vivo orthotopic U87MG glioma model confirms that the released ATMO‐21 shows significant therapeutic efficacy in inhibiting tumor growth and angiogenesis, demonstrating that agonist‐modified SpAcDex NPs represent a promising strategy for GBM treatment combining targeted gene therapy and antiangiogenic therapy.
3D‐Printed Strong Dental Crown with Multi‐Scale Ordered Architecture, High‐Precision, and Bioactivity
Authors: Zhao Menglu , Yang Danlei , Fan Suna , Yao Xiang , Wang Jiexin , Zhu Meifang , Zhang Yaopeng 
Published: December 2021

AbstractMimicking the multi‐scale highly ordered hydroxyapatite (HAp) nanocrystal structure of the natural tooth enamel remains a great challenge. Herein, a bottom‐up step‐by‐step strategy is developed using extrusion‐based 3D printing technology to achieve a high‐precision dental crown with multi‐scale highly ordered HAp structure. In this study, hybrid resin‐based composites (RBCs) with “supergravity +” HAp nanorods can be printed smoothly via direct ink writing (DIW) 3D printing, induced by shear force through a custom‐built nozzle with a gradually shrinking channel. The theoretical simulation results of finite element method are consistent with the experimental results. The HAp nanorods are first highly oriented along a programmable printing direction in a single printed fiber, then arranged in a layer by adjusting the printing path, and finally 3D printed into a highly ordered and complex crown structure. The printed samples with criss‐crossed layers by interrupting crack propagation exhibit a flexural strength of 134.1 ± 3.9 MPa and a compressive strength of 361.6 ± 8.9 MPa, which are superior to the corresponding values of traditional molding counterparts. The HAp‐monodispersed RBCs are successfully used to print strong and bioactive dental crowns with a printing accuracy of 95%. This new approach can help provide customized components for the clinical restoration of teeth.
Photoinduced Multistable Resonance Frequency Switching of Phase Change Microstring at Room Temperature
Authors: Bukhari Syed A. , McGee Ryan , Mahdavi Amirhossein , Bensebaa Farid , Zhou Liang , Chung Hyun‐Joong , Thundat Thomas , Goswami Ankur 
Published: December 2021

AbstractVanadium dioxide (VO2), a promising phase change material, exhibits insulator to metal transition at 68 °C, manifests a drastic change in multiple physical properties, such as electrical resistance, mechanical modulus, lattice parameters, etc. From technological perspective, the transition temperature can be reduced by precise strain engineering. Here a noncontact, all‐optical, and highly energy efficient platform is demonstrated to study macroscopic dynamics related to the localized structural rearrangements at room temperature. A thin layer (≈25 nm) of polycrystalline VO2 deposited on a platinum coated silicon nitride microstring resonator shows a fast controlled mechanical resonance frequency response upon variations in optical power and wavelength. It is shown multiple stable frequencies of the resonator, designated as different equilibrium states, can be activated at different optical powers (≈200 µW) and wavelength, i.e., 450, 520, and 635 nm. The observed multiple resonance states of the microstring are explained because of the generation of stress due to the interplay between thermal expansion and the temperature‐induced phase change of VO2. It is believed this change in frequency states under the controlled external optical excitation can have potential applications in ultrafast optical switching, intelligent temperature sensors, and neuromorphic devices operated at room temperature.
Graphene Acid for Lithium‐Ion Batteries—Carboxylation Boosts Storage Capacity in Graphene
Authors: Obraztsov Ievgen , Bakandritsos Aristides , Šedajová Veronika , Langer Rostislav , Jakubec Petr , Zoppellaro Giorgio , Pykal Martin , Presser Volker , Otyepka Michal , Zbořil Radek 
Published: December 2021

AbstractEnvironmentally sustainable, low‐cost, flexible, and lightweight energy storage technologies require advancement in materials design in order to obtain more efficient organic metal‐ion batteries. Synthetically tailored organic molecules, which react reversibly with lithium, may address the need for cost‐effective and eco‐friendly anodes used for organic/lithium battery technologies. Among them, carboxylic group‐bearing molecules act as high‐energy content anodes. Although organic molecules offer rich chemistry, allowing a high content of carboxyl groups to be installed on aromatic rings, they suffer from low conductivity and leakage to the electrolytes, which restricts their actual capacity, the charging/discharging rate, and eventually their application potential. Here, a densely carboxylated but conducting graphene derivative (graphene acid (GA)) is designed to circumvent these critical limitations, enabling effective operation without compromising the mechanical or chemical stability of the electrode. Experiments including operando Raman measurements and theoretical calculations reveal the excellent charge transport, redox activity, and lithium intercalation properties of the GA anode at the single‐layer level, outperforming all reported organic anodes, including commercial monolayer graphene and graphene nanoplatelets. The practical capacity and rate capability of 800 mAh g−1 at 0.05 A g−1 and 174 mAh g−1 at 2.0 A g−1 demonstrate the true potential of GA anodes in advanced lithium‐ion batteries.