bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cellulose Nanomaterials in Interfacial Evaporators for Desalination: A “Natural” Choice
Authors: Cao Sisi , Rathi Priya , Wu Xuanhao , Ghim Deoukchen , Jun Young‐Shin , Singamaneni Srikanth 
Published: June 2020

AbstractHerein, the recent advances in realizing highly efficient cellulose‐based solar evaporators for alleviating the global water crisis are summarized. Fresh water scarcity is one of the most threatening issues for sustainable development. Solar steam generation, which harnesses the abundant sunlight, has been recognized as a sustainable approach to harvest fresh water. In contrast to synthetic polymeric materials that can pose serious negative environmental impacts, cellulose‐based materials, owing to their biocompatibility, renewability, and sustainability, are highly attractive for realizing solar steam generators. The molecular and macromolecular features of cellulose and the physicochemical properties of extracted cellulose nanoparticles (cellulose nanocrystals and cellulose nanofibrils (CNF)) and natural cellulose materials (wood and bacterial nanocellulose (BNC)) that make them attractive as supporting substrate materials in solar steam generators are briefly discussed. Recent progress in designing highly efficient cellulose‐based solar evaporators, including utilizing extracted cellulose nanoparticles via bottom‐up assembly CNF, natural cellulose materials with intrinsic hierarchical structure (wood and BNC), and commercial planar cellulose substrates (air‐laid paper, cellulose paper, and cotton fabric) is reviewed. The outstanding challenges that need to be addressed for these materials and devices to be utilized in the real‐world and in overcoming global water crisis are also briefly highlighted.
Controllable Singlet–Triplet Energy Splitting of Graphene Quantum Dots through Oxidation: From Phosphorescence to TADF
Authors: Park Minsu , Kim Hyung Suk , Yoon Hyewon , Kim Jin , Lee Sukki , Yoo Seunghyup , Jeon Seokwoo 
Published: June 2020

AbstractLong‐lived afterglow emissions, such as room‐temperature phosphorescence (RTP) and thermally activated delayed fluorescence (TADF), are beneficial in the fields of displays, bioimaging, and data security. However, it is challenging to realize a single material that simultaneously exhibits both RTP and TADF properties with their relative strengths varied in a controlled manner. Herein, a new design approach is reported to control singlet–triplet energy splitting (∆EST) in graphene quantum dots (GQD)/graphene oxide quantum dots (GOQDs) by varying the ratio of oxygenated carbon to sp2 carbon (γOC). It is demonstrated that ∆EST decreases from 0.365 to 0.123 eV as γOC increases from 4.63% to 59.6%, which in turn induces a dramatic transition from RTP to TADF. Matrix‐assisted stabilization of triplet excited states provides ultralong lifetimes to both RTP and TADF. Embedded in boron oxynitride, the low oxidized (4.63%) GQD exhibits an RTP lifetime (τTavg) of 783 ms, and the highly oxidized (59.6%) GOQD exhibits a TADF lifetime (τDFavg) of 125 ms. Furthermore, the long‐lived RTP and TADF materials enable the first demonstration of anticounterfeiting and multilevel information security using GQD. These results will open up a new approach to the engineering of singlet–triplet splitting in GQD for controlled realization of smart multimodal afterglow materials.
Mesoporous PdAg Nanospheres for Stable Electrochemical CO2 Reduction to Formate
Authors: Zhou Yuan , Zhou Rui , Zhu Xiaorong , Han Na , Song Bin , Liu Tongchao , Hu Guangzhi , Li Yafei , Lu Jun , Li Yanguang 
Published: June 2020

AbstractPalladium is a promising material for electrochemical CO2 reduction to formate with high Faradaic efficiency near the equilibrium potential. It unfortunately suffers from problematic operation stability due to CO poisoning on surface. Here, it is demonstrated that alloying is an effective strategy to alleviate this problem. Mesoporous PdAg nanospheres with uniform size and composition are prepared from the co‐reduction of palladium and silver precursors in aqueous solution using dioctadecyldimethylammonium chloride as the structure‐directing agent. The best candidate can initiate CO2 reduction at zero overpotential and achieve high formate selectivity close to 100% and great stability even at <‐0.2 V versus reversible hydrogen electrode. The high selectivity and stability are believed to result from the electronic coupling between Pd and Ag, which lowers the d‐band center of Pd and thereby significantly enhances its CO tolerance, as evidenced by both electrochemical analysis and theoretical simulations.
Changes of Structure and Bonding with Thickness in Chalcogenide Thin Films
Authors: Ronneberger Ider , Zanolli Zeila , Wuttig Matthias , Mazzarello Riccardo 
Published: June 2020

AbstractExtreme miniaturization is known to be detrimental for certain properties, such as ferroelectricity in perovskite oxide films below a critical thickness. Remarkably, few‐layer crystalline films of monochalcogenides display robust in‐plane ferroelectricity with potential applications in nanoelectronics. These applications critically depend on the electronic properties and the nature of bonding in the 2D limit. A fundamental open question is thus to what extent bulk properties persist in thin films. Here, this question is addressed by a first‐principles study of the structural, electronic, and ferroelectric properties of selected monochalcogenides (GeSe, GeTe, SnSe, and SnTe) as a function of film thickness up to 18 bilayers. While in selenides a few bilayers are sufficient to recover the bulk behavior, the Te‐based compounds deviate strongly from the bulk, irrespective of the slab thickness. These results are explained in terms of depolarizing fields in Te‐based slabs and the different nature of the chemical bond in selenides and tellurides. It is shown that GeTe and SnTe slabs inherit metavalent bonding of the bulk phase, despite structural and electronic properties being strongly modified in thin films. This understanding of the nature of bonding in few‐layers structures offers a powerful tool to tune materials properties for applications in information technology.
Lipid‐Bilayer‐Supported 3D Printing of Human Cerebral Cortex Cells Reveals Developmental Interactions
Authors: Zhou Linna , Wolfes Anne C. , Li Yichen , Chan Danny C. W. , Ko Ho , Szele Francis G. , Bayley Hagan 
Published: June 2020

AbstractCurrent understanding of human brain development is rudimentary due to suboptimal in vitro and animal models. In particular, how initial cell positions impact subsequent human cortical development is unclear because experimental spatial control of cortical cell arrangement is technically challenging. 3D cell printing provides a rapid customized approach for patterning. However, it has relied on materials that do not represent the extracellular matrix (ECM) of brain tissue. Therefore, in the present work, a lipid‐bilayer‐supported printing technique is developed to 3D print human cortical cells in the soft, biocompatible ECM, Matrigel. Printed human neural stem cells (hNSCs) show high viability, neural differentiation, and the formation of functional, stimulus‐responsive neural networks. By using prepatterned arrangements of neurons and astrocytes, it is found that hNSC process outgrowth and migration into cell‐free matrix and into astrocyte‐containing matrix are similar in extent. However, astrocytes enhance the later developmental event of axon bundling. Both young and mature neurons migrate into compartments containing astrocytes; in contrast, astrocytes do not migrate into neuronal domains signifying nonreciprocal chemorepulsion. Therefore, precise prepatterning by 3D printing allows the construction of natural and unnatural patterns that yield important insights into human cerebral cortex development.
Fully Inkjet‐Printed, Ultrathin and Conformable Organic Photovoltaics as Power Source Based on Cross‐Linked PEDOT:PSS Electrodes
Authors: Bihar Eloïse , Corzo Daniel , Hidalgo Tania C. , Rosas‐Villalva Diego , Salama Khaled N. , Inal Sahika , Baran Derya 
Published: June 2020

AbstractUltra‐lightweight solar cells have attracted enormous attention due to their ultra‐conformability, flexibility, and compatibility with applications including electronic skin or miniaturized electronics for biological applications. With the latest advancements in printing technologies, printing ultrathin electronics is becoming now a reality. This work offers an easy path to fabricate indium tin oxide (ITO)‐free ultra‐lightweight organic solar cells through inkjet‐printing while preserving high efficiencies. A method consisting of the modification of a poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) ink with a methoxysilane‐based cross‐linker (3‐glycidyloxypropyl)trimethoxysilane (GOPS)) is presented to chemically modify the structure of the electrode layer. Combined with plasma and solvent post‐treatments, this approach prevents shunts and ensures precise patterning of solar cells. By using poly(3‐hexylthiophene) along rhodanine‐benzothiadiazole‐coupled indacenodithiophene (P3HT:O‐IDTBR), the power conversion efficiency (PCE) of the fully printed solar cells is boosted up to 4.73% and fill factors approaching 65%. All inkjet‐printed ultrathin solar cells on a 1.7 µm thick biocompatible parylene substrate are fabricated with PCE reaching up to 3.6% and high power‐per‐weight values of 6.3 W g−1. After encapsulation, the cells retain their performance after being exposed for 6 h to aqueous environments such as water, seawater, or phosphate buffered saline, paving the way for their integration in more complex circuits for biological systems.
Selective and Sensitive Photon Sieve Based on III–V Semiconductor Nanowire Forest Fabricated by Lithography‐Free Process
Authors: Lee Gil Ju , Park Kwangwook , Kim Min Seok , Chang Sehui , Seok Tae Joon , Park Hong‐Gyu , Ju Gunwu , Kim Kyujung , Song Young Min 
Published: June 2020

AbstractVertically oriented semiconductor nanowires (NWs) have been intensely studied in macroscopic perspective due to their attractive applications such as optical filters, photodiodes, and solar cells. However, microscopic photonic phenomena of dense and random NWs have been rarely, and their promising applications have not been explored. Therefore, this article theoretically and experimentally investigates the microscopic photonic event of dense and random NWs using highly selective and sensitive photon sieve (SSPS), which employs highly populated III/V semiconductor NW forests fabricated with a lithography‐free self‐catalyzed growth method. Theoretical analyses reveal that diameter‐dependent and selective photon absorption occurs even for a dense and disordered NW distribution. The engineered growth process affords highly populated NW forests (mean shortest interval = 192.4 nm) comprising NWs with a high aspect ratio (mean aspect ratio = 34.3) and a sufficiently broad diameter distribution to span the visible spectrum and decompose it (mean diameter = 94 nm, standard deviation = 49 nm). Moreover, the SSPS exhibits unique spectral responses to monochromatic light of different wavelengths (correlation coefficients < 0.03) and a high sensitivity with a highest absorptivity of 92.4%. This work indicates SSPSs can be utilized for various applications of artificial photoreceptor, physically unclonable function, and high efficient optoelectronics.
Dual‐Function Fluorescent Covalent Organic Frameworks: HCl Sensing and Photocatalytic H2 Evolution from Water
Authors: EL‐Mahdy Ahmed F. M. , Elewa Ahmed M. , Huang Sheng‐Wen , Chou Ho‐Hsiu , Kuo Shiao‐Wei 
Published: June 2020

AbstractTwo ultrastable luminescent covalent organic frameworks (COFs), PyTA‐BC and PyTA‐BC‐Ph, are synthesized through polycondensations of 4,4′,4″,4′″‐pyrene‐1,3,6,8‐tetrayl)tetraaniline (PyTA‐4NH2) with two carbazole‐based derivatives having different degrees of conjugation. The PyTA‐BC and PyTA‐BC‐Ph COFs exhibit ultrahigh thermal stabilities (up to 421 °C), excellent crystallinity, and high Brunauer–Emmett–Teller surface areas (up to 1445 m2 g−1). These COFs display strong fluorescence emissions in various solvents, with their emission maxima gradually red‐shifting upon increasing the polarity of the solvent (solvatochromism). Upon exposure to HCl, they respond very rapidly and sensitively in terms of changing their colors and fluorescence emission maxima. In the presence of a sacrificial electron donor, these COFs mediate the highly efficient photocatalytic evolution of H2 from water. In the absence of a noble metal cocatalyst, the COFs and ascorbic acid provide a photocatalytic H2 production of up to 1183 µmol g−1 h−1 (λ ≥ 420 nm); this value is the highest reported to date for a COF. Such COFs appear to be potentially useful as chemosensors for the naked‐eye and sensitive spectroscopic detection of HCl and as cocatalysts for the sustainable photocatalytic production of H2 from water.
Reversible Emitting Anti‐Counterfeiting Ink Prepared by Anthraquinone‐Modified β‐Cyclodextrin Supramolecular Polymer
Authors: Chen Lei , Chen Yong , Fu Hong‐Guang , Liu Yu 
Published: June 2020

AbstractIntelligent fluorescent materials have been paid more and more attention due to their wide application in information encryption and anti‐counterfeiting materials. Herein, a supramolecular polymer is constructed through the host–guest interaction of anthraquinone‐modified β‐cyclodextrin (AQ‐β‐CD) in aqueous solution. Thanks to the hydrophobic microenvironment of the cyclodextrin cavity and the shielding effect on oxygen molecules, the anthraquinone group, as the guest molecule, can rapidly produce 9,10‐anthracenediol (QH2) with strong fluorescence by photoreduction. Interestingly, the generated anthracenediol group is still sensitive to oxygen and can be converted to anthraquinone by oxygen. Significantly, aqueous solution of AQ‐β‐CD supermolecular polymer is used as emitting ink, which decrypts the information by ultraviolet light and encrypts the information in the air.
Axially Chiral Biphenyl Compound‐Based Thermally Activated Delayed Fluorescent Materials for High‐Performance Circularly Polarized Organic Light‐Emitting Diodes
Authors: Tu Zhen‐Long , Yan Zhi‐Ping , Liang Xiao , Chen Lei , Wu Zheng‐Guang , Wang Yi , Zheng You‐Xuan , Zuo Jing‐Lin , Pan Yi 
Published: June 2020

AbstractTo boost intrinsic circularly polarized luminescence (CPL) properties of chiral emitters, an axially chiral biphenyl unit is inlaid in thermally activated delayed fluorescent (TADF) skeleton, urging the participation of chiral source in frontier molecular orbital distributions. A pair of enantiomers, (R)‐BPPOACZ and (S)‐BPPOACZ, containing the cyano as electron‐withdrawing moieties and carbazole and phenoxazine as electron‐donating units are synthesized and separated. The circularly polarized TADF enantiomers exhibit both high photoluminescence quantum yield of 86.10% and excellent CPL activities with maximum dissymmetry factor |gPL| values of almost 10−2 in solution and 1.8 × 10−2 in doped film, which are among the best values of previously reported small chiral organic materials. Moreover, the circularly polarized organic light‐emitting diodes based on the TADF enantiomers achieve the maximum external quantum efficiency of 16.6% with extremely low efficiency roll‐off. Obvious circularly polarized electroluminescence signals with |gEL| values of 4 × 10−3 are also recorded.
Development and Applications of Water‐based Extraction Methods in Natural Products Isolation Chemistry
Authors: Deans Bianca J. , Just Jeremy , Smith Jason A. , Bissember Alex C. 
Published: June 2020

AbstractThis minireview presents and discusses natural product isolation studies that have been facilitated using predominately water‐based extraction methods over the past twenty years. The development and applications of new techniques for enabling natural products chemistry are examined. This includes techniques such as accelerated solvent extraction (ASE) and pressurised hot water extraction (PHWE). The latter, in particular, arguably represents an emerging approach that can allow for the rapid, efficient, and practical extraction of natural products by more environmentally‐benign approaches.
Activity‐Based Genetically Encoded Fluorescent and Luminescent Probes for Detecting Formaldehyde in Living Cells
Authors: Zhang Yuqing , Du Yimeng , Li Manjia , Zhang Dong , Xiang Zheng , Peng Tao 
Published: June 2020

AbstractFormaldehyde (FA) is endogenously produced in living systems through a variety of biological processes and has been implicated in many pathological conditions. Detection tools for biological FA are therefore of great interest. Reported here are novel activity‐based genetically encoded fluorescent and luminescent probes for detecting FA in aqueous solutions and living mammalian cells. A FA‐reactive lysine analogue, PrAK, was site‐specifically incorporated into the essential lysine sites of enhanced green fluorescent protein (EGFP) and firefly luciferase (fLuc) to afford fluorescent and luminescent FA probes, respectively. FA selectively reacts with PrAK residues on EGFP and fLuc through a 2‐aza‐Cope rearrangement, resulting in fluorescence and luminescence turn‐on responses, respectively, to FA selectively over potentially interfering reactive species in aqueous buffer. Moreover, the genetically encoded probes are capable of visualizing FA at physiologically relevant levels in living mammalian cells by fluorescence and luminescence imaging, demonstrating their potential as new tools to explore FA biology.
Benetzungsvorgänge und ihr Einfluss auf die elektrochemischen Eigenschaften von oberflächenangepassten Lithium‐Metall‐Elektroden in Kontakt mit quervernetzten Polymer‐Elektrolyten
Authors: Zhang Mengyi , Becking Jens , Stan Marian Cristian , Lenoch Arthur , Bieker Peter , Kolek Martin , Winter Martin 
Published: June 2020

AbstractLithium‐Metall‐Batterien (LMBs) auf Basis von vernetzten Polymer‐Elektrolyten (PEs) sind vielversprechende Kandidaten für Batterien der nächsten Generation. Das Benetzungsverhalten von PEs auf unebenen Lithium‐Metall‐Oberflächen wurde jedoch in den meisten Studien bisher vernachlässigt. Hier wird gezeigt, dass mikroskalige Defektstellen mit gekrümmten Kanten eine entscheidende Rolle bei der benetzungsabhängigen, elektrochemischen Abscheidung von Lithium (Li) spielen. Die Benetzbarkeit und die viskoelastischen Eigenschaften von PEs werden in Zusammenhang gebracht und es wird der Einfluss der Benetzbarkeit auf die Keimbildung und Diffusion in der Nähe der Li|PE‐Grenzfläche untersucht. Es wird festgestellt, dass die Krümmung der Kanten an Li‐Defektstellen ein entscheidender Einflussfaktor für die Untersuchung von Benetzungsphänomenen ist. Das Auftreten von mikroskaligen Defekten und partieller Phasenseparation werden als Kernpunkte für unregelmäßige Nukleation identifiziert. Es wird betont, dass für eine stabile und beständige Langzeit‐Zyklenstabilität von PE‐basierten LMBs ein tieferes Verständnis des “weichen Festkörper”‐Festkörper‐Kontakts zwischen PEs und intrinsisch rauen Li‐Metall‐Oberflächen erforderlich ist.
Dual Role of Silver Moieties Coupled with Ordered Mesoporous Cobalt Oxide towards Electrocatalytic Oxygen Evolution Reaction
Authors: Yu Mingquan , Moon Gun‐hee , Castillo Rebeca G. , DeBeer Serena , Weidenthaler Claudia , Tüysüz Harun 
Published: June 2020

AbstractHerein, we show that the performance of mesostructured cobalt oxide electrocatalyst for oxygen evolution reaction (OER) can be significantly enhanced by coupling of silver species. Various analysis techniques including pair distribution function and Rietveld refinement, X‐ray absorption spectroscopy at synchrotron as well as advanced electron microscopy revealed that silver exists as metallic Ag particles and well‐dispersed Ag2O nanoclusters within the mesostructure. The benefits of this synergy are twofold for OER: highly conductive metallic Ag improves the charge transfer ability of the electrocatalysts while ultra‐small Ag2O clusters provide the centers that can uptake Fe impurities from KOH electrolyte and boost the catalytic efficiency of Co–Ag oxides. The current density of mesostructured Co3O4 at 1.7 VRHE is increased from 102 to 211 mA cm−2 with incorporation of silver spices. This work presents the dual role of silver moieties and demonstrates a simple method to increase the OER activity of Co3O4.
Sensitive Morphological Characterization of Oriented High‐Density Lipoprotein Nanoparticles Using 31P NMR Spectroscopy
Authors: Lau Sophie , Middleton David A. 
Published: June 2020

AbstractThe biological function of high‐density lipoprotein (HDL) nanoparticles, the so‐called good cholesterol that is associated with a low risk of heart disease, depends on their composition, morphology, and size. The morphology of HDL particles composed of apolipoproteins, lipids and cholesterol is routinely visualised by transmission electron microscopy (TEM), but higher‐resolution tools are needed to observe more subtle structural differences between particles of different composition. Here, reconstituted HDL formulations are oriented on glass substrates and solid‐state 31P NMR spectroscopy is shown to be highly sensitive to the surface curvature of the lipid headgroups. The spectra report potentially functionally important differences in the morphology of different HDL preparations that are not detected by TEM. This method provides new morphological insights into HDL comprising a naturally occurring apolipoprotein A‐I mutant, which may be linked to its atheroprotective properties, and holds promise as a future research tool in the clinical analysis of plasma HDL.
Highly Conducting and Flexible Radical Crystals
Authors: Kwon Taeyeon , Koo Jin Young , Choi Hee Cheul 
Published: June 2020

AbstractTogether with high conductivity, high flexibility is an important property required for next generation organic electronic components. Both properties are difficult to achieve together especially when the components are crystalline because of the intrinsic high brittleness of organic molecular crystals. We report an organic radical crystal system that has both high flexibility and high conductivity. The crystal consists of 9,10‐bis(phenylethynyl)anthracene radical cation (BPEA.+) units, and shows flexibility under pressure with high conductivity in ambient condition exhibiting average conductivity of 2.68 S cm−1 when normal linear shape, as well as 2.43 S cm−1 when bent. The structural analysis reveals that both a short π–π distance (3.290 Å) between BPEA.+ units that are aligned along the crystal length direction, and the presence of PF6− counter ions induce flexibility and high electrical conductivity.
TEAD–YAP Interaction Inhibitors and MDM2 Binders from DNA‐Encoded Indole‐Focused Ugi Peptidomimetics
Authors: Kunig Verena B. K. , Potowski Marco , Akbarzadeh Mohammad , Klika Škopić Mateja , dos Santos Smith Denise , Arendt Lukas , Dormuth Ina , Adihou Hélène , Andlovic Blaž , Karatas Hacer , Shaabani Shabnam , Zarganes‐Tzitzikas Tryfon , Neochoritis Constantinos G. , Zhang Ran , Groves Matthew , Guéret Stéphanie M. , Ottmann Christian , Rahnenführer Jörg , Fried Roland , Dömling Alexander , Brunschweiger Andreas 
Published: June 2020

AbstractDNA‐encoded combinatorial synthesis provides efficient and dense coverage of chemical space around privileged molecular structures. The indole side chain of tryptophan plays a prominent role in key, or “hot spot”, regions of protein–protein interactions. A DNA‐encoded combinatorial peptoid library was designed based on the Ugi four‐component reaction by employing tryptophan‐mimetic indole side chains to probe the surface of target proteins. Several peptoids were synthesized on a chemically stable hexathymidine adapter oligonucleotide “hexT”, encoded by DNA sequences, and substituted by azide‐alkyne cycloaddition to yield a library of 8112 molecules. Selection experiments for the tumor‐relevant proteins MDM2 and TEAD4 yielded MDM2 binders and a novel class of TEAD‐YAP interaction inhibitors that perturbed the expression of a gene under the control of these Hippo pathway effectors.