bluuebunny/crossref_metadata_2025_split huggingface dataset:
Unlocking Full Discharge Capacities of Poly(vinylphenothiazine) as Battery Cathode Material by Decreasing Polymer Mobility Through Cross‐Linking
Authors: Otteny Fabian , Kolek Martin , Becking Jens , Winter Martin , Bieker Peter , Esser Birgit 
Published: October 2018

AbstractOrganic cathode materials are a sustainable alternative to transition metal oxide‐based compounds in high voltage rechargeable batteries due to their low toxicity and availability from less‐limited resources. Important criteria in their design are a high specific capacity, cycling stability, and rate capability. Furthermore, the cathode should contain a high mass loading of active material and be compatible with different anode materials, allowing for its use in a variety of cell designs. Here, cross‐linked poly(3‐vinyl‐N‐methylphenothiazine) as cathode‐active material is presented, which shows a remarkable rate capability (up to 10C) and cycling stability at a high and stable potential of 3.55 V versus Li/Li+ and a specific capacity of 112 mAh g−1. Its use in full cells with a high mass loading of 70 wt% is demonstrated against lithium titanate as intercalation material as well as lithium metal, which both show excellent performance. Through comparison with poly(3‐vinyl‐N‐methylphenothiazine) the study shows that changing the structure of the redox‐active polymer through cross‐linking can lead to a change in charge/discharge mechanism and cycling behavior of the composite electrode. Poly(3‐vinyl‐N‐methylphenothiazine) in its cross‐ and non‐cross‐linked form both show excellent results as cathode‐active materials with variable specifications regarding specific capacity, cycling stability, and rate capability.
Fermi Level Positions and Induced Band Bending at Single Crystalline Anatase (101) and (001) Surfaces: Origin of the Enhanced Photocatalytic Activity of Facet Engineered Crystals
Authors: Kashiwaya Shun , Toupance Thierry , Klein Andreas , Jaegermann Wolfram 
Published: October 2018

AbstractSingle crystalline anatase is used to prepare well defined (001) and (101) surfaces in ultrahigh vacuum (UHV) in different states: sputtered, annealed, stoichiometric, and oxidized. The electronic properties of the well‐defined surfaces are investigated by X‐ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy after UHV transfer. The Fermi level of (001) facets for all applied surface conditions is lower than that of the (101) facets by 150–450 meV. The energy difference leads to a potential difference (band bending) at the interface between the (101) and (001) facets, resulting in the migration of photogenerated electrons and holes to different directions namely to the (101) and (001) facets, respectively. Photoelectron spectroscopy measurements clearly indicate for the first time that differences in the surface electronic structure and related potential of different facets explain a vectorial electron–hole pair separation to different reaction sites providing design criteria for enhanced photocatalysis.
Micro‐/Nanohoneycomb Solid Oxide Electrolysis Cell Anodes with Ultralarge Current Tolerance
Authors: Wu Tong , Zhang Wenqiang , Li Yifeng , Zheng Yun , Yu Bo , Chen Jing , Sun Xiaoming 
Published: October 2018

AbstractAs a clean, efficient, and promising energy conversion device, solid oxide electrolysis cell (SOEC), which can achieve transformation from electricity to chemical fuels, has captured worldwide attention. A novel biomimetic honeycomb SOEC anode with super low tortuosity factor (≈1), ground‐breaking porosity (≈75%), and high structural strength, has been successfully fabricated by freeze casting and infiltrating. This honeycomb anode demonstrates ultralow polarization resistance (0.0094 Ω cm2, lower than any existing anodes reported so far) and high durability for hours at a large current density of 2.0 A cm−2 at 800 °C. These unique advantages are derived from the effective release of oxygen through the yttria‐stabilized zirconia honeycomb skeletons, and the exposure of active areas along the inner pore of the honeycomb structure after infiltrating La0.6Sr0.4CoO3±δ. Such a honeycomb electrode combines high electrical, chemical, and thermal stability under high temperatures and large current densities, demonstrating the feasibility of biomimetic structures for use in large‐scale and highly efficient energy conversion systems.
Carbon Nanodot Additives Realize High‐Performance Air‐Stable p–i–n Perovskite Solar Cells Providing Efficiencies of up to 20.2%
Authors: Hsu Hsiang‐Lin , Hsiao Hsiang‐Tse , Juang Tzong‐Yuan , Jiang Bing‐Huang , Chen Sheng‐Chi , Jeng Ru‐Jong , Chen Chih‐Ping 
Published: October 2018

AbstractCarbonized bamboo‐derived carbon nanodots (CNDs) as efficient additives for application in perovskite solar cells (PSCs) are reported. These carboxylic acid‐ and hydroxyl‐rich CNDs interact with the perovskite through hydrogen bonds and, thereby, promote the carriers' lifetimes and realize high‐performance p–i–n PSCs having the structure indium tin oxide/NiOx/CH3NH3PbI3 (MAPbI3)/PC61BM/BCP/Ag. As a result of interactions between the CNDs and the perovskite, the presence of the nonvolatile CND additive increases the power conversion efficiency (PCE) of the PSC from 14.48% ± 0.39% to 16.47% ± 0.26%. Furthermore, adding urea, a Lewis base, increases the PCE to 20.2%—the result of a significant increase in the crystal size and a lower content of grain boundary defects and, therefore, longer carrier lifetimes. Cells containing these two additives (without encapsulation) exhibit excellent shelf‐life and air‐stability, maintaining their high PCEs after storage in air—at a temperature of 25 °C and a humidity of 40%—for over 500 h. This performance is among of the best ever reported for p–i–n PSC devices incorporating carbon‐based additives.
Efficient and Air‐Stable Aqueous‐Processed Organic Solar Cells and Transistors: Impact of Water Addition on Processability and Thin‐Film Morphologies of Electroactive Materials
Authors: Lee Changyeon , Lee Hae Rang , Choi Joonhyeong , Kim Youngkwon , Nguyen Thanh Luan , Lee Wonho , Gautam Bhoj , Liu Xiang , Zhang Kai , Huang Fei , Oh Joon Hak , Woo Han Young , Kim Bumjoon J. 
Published: October 2018

AbstractThe authors report the development of a desirable aqueous process for ecofriendly fabrication of efficient and stable organic field‐effect transistors (eco‐OFETs) and polymer solar cells (eco‐PSCs). Intriguingly, the addition of a typical antisolvent, water, to ethanol is found to remarkably enhance the solubility of oligoethylene glycol (OEG) side chain‐based electroactive materials (e.g., the highly crystalline conjugated polymer PPDT2FBT‐A and the fullerene monoadduct PC61BO12). A water–ethanol cosolvent with a 1:1 molar ratio provides an increased solubility of PPDT2FBT‐A from 2.3 to 42.9 mg mL−1 and that of PC61BO12 from 0.3 to 40.5 mg mL−1. Owing to the improved processability, efficient eco‐OFETs with a hole mobility of 2.0 × 10−2 cm2 V−1 s−1 and eco‐PSCs with a power conversion efficiency of 2.05% are successfully fabricated. In addition, the eco‐PSCs fabricated with water–ethanol processing are highly stable under ambient conditions, showing the great potential of this new process for industrial scale application. To better understand the underlying role of water addition, the influence of water addition on the thin‐film morphologies and the performance of the eco‐OFETs and eco‐PSCs are studied. Additionally, it is demonstrated that the application of the aqueous process can be extended to a variety of other OEG‐based material systems.
Air‐drying with ionic liquids
Authors: Yu Gangqiang , Sui Xiaohui , Lei Zhigang , Dai Chengna , Chen Biaohua 
Published: October 2018

SignificanceIonic liquids (ILs) are employed for air‐drying for the first time. The experimental gas–liquid equilibrium (EQ) of N2/O2 + [EMIM][BF4] and N2/O2 + [EMIM][BF4] + H2O systems under a broad temperature range are measured. The new modified UNIFAC‐Lei model is successfully extended to predict the N2/O2‐IL‐H2O system based on extensive phase EQ data. The air‐drying experiment using [EMIM][BF4] as an absorbent is conducted, confirming that this new technology is effective and efficient. © 2018 American Institute of Chemical Engineers AIChE J, 65: 479–482, 2019
Epiphyseal fusion and dental development in Pan paniscus with comparisons with Pan troglodytes
Authors: Brimacombe Conrad S. , Kuykendall Kevin L. , Nystrom Pia 
Published: October 2018

AbstractObjectivesCompared with frequent studies of skeletal development in chimpanzees, relatively little is known about bonobo skeletal development. This study seeks to explore the relationship between skeletal and dental development in both species of Pan. New data are presented for fusion sites not previously observed in bonobos.Materials and methodsIn a sample of 34 Pan paniscus and 168 Pan troglodytes subadults, state of fusion was recorded for 30 epiphyseal fusion sites using a three‐stage system of unfused, midfusion, and complete fusion based on Wintheiser, Clauser, and Tappen. Stage of dental development for permanent mandibular dentition was assessed using the Demrijian, Goldstein, and Tanner method. These data allowed for comparisons of both species of Pan and the two subspecies of P. troglodytes.ResultsThe sequence of fusion events was generally consistent between the two species, but some exceptions may exist for the knee and ankle. The number of fusion events that occurred after complete dental mineralization was similar in both species. No statistically significant differences were found in the fusion timing for the subspecies of P. troglodytes.DiscussionBolter and Zihlman suggested that fusion at the acetabulum occurs earlier in Pan paniscus, while fusion of epiphyses at the knee are delayed, compared with P. troglodytes. Our data do not indicate earlier fusion of the acetabulum, but fusion events at the knee may complete later relative to dental mineralization in Pan pansicus. Compared with Homo sapiens, both P. troglodytes and Pan paniscus demonstrate later completion of epiphyseal fusion relative to dental mineralization.
Solid‐State Umbrella‐type Inversion of a VO5 Square‐Pyramidal Unit in a Bowl‐type Dodecavanadate Induced by Insertion and Elimination of a Guest Molecule
Authors: Kikukawa Yuji , Seto Kensuke , Uchida Sayaka , Kuwajima Sho , Hayashi Yoshihito 
Published: October 2018

AbstractDesign of cavities for a target molecule and the elucidation of the corresponding host–guest interactions are important for molecular manipulation. A discrete dodecavanadate bowl, [V12O32]4− (V12), with an entrance diameter of 4.4 Å and an electron‐rich guest at the center of the bowl, was stabilized by electrostatic interactions. A characteristic of V12 is a solid‐state polytopal rearrangement during guest elimination and recapture. A guest‐free dodecavanadate, [V12O32]4− (V12‐free), was prepared by removal of the guest from CH2Cl2‐inserted V12 under vacuum at 50 °C. Single‐crystal X‐ray analysis revealed that one of the VO5 square pyramids at the bottom of V12‐free was inverted to fill the void of the bowl cavity. The exposure of V12‐free to the guest molecule vapors of CH2Cl2, 1,2‐dichloroethane, MeNO2, MeCN, and MeBr resulted in the selective insertion of the guest to reform the guest‐inserted V12 structure. Whereas CO2 could be inserted in the V12 bowl, CH4 and CO could not.
Non‐3d Metal Modulation of a Cobalt Imidazolate Framework for Excellent Electrocatalytic Oxygen Evolution in Neutral Media
Authors: Xu Yan‐Tong , Ye Zi‐Ming , Ye Jia‐Wen , Cao Li‐Ming , Huang Rui‐Kang , Wu Jun‐Xi , Zhou Dong‐Dong , Zhang Xue‐Feng , He Chun‐Ting , Zhang Jie‐Peng , Chen Xiao‐Ming 
Published: October 2018

AbstractCobalt imidazolate frameworks are classical electrocatalysts for the oxygen evolution reaction (OER) but suffer from the relatively low activity. Here, a non‐3d metal modulation strategy is presented for enhancing the OER activity of cobalt imidazolate frameworks. Two isomorphous frameworks [Co4(MO4)(eim)6] (M=Mo or W, Heim=2‐ethylimidazole) having Co(eim)3(MO4) units and high water stabilities were designed and synthesized. In different neutral media, the Mo‐modulated framework coated on a glassy carbon electrode shows the best OER performances (1 mA cm−2 at an overpotential of 210 mV in CO2‐saturated 0.5 m KHCO3 electrolyte and 2/10/22 mA cm−2 at overpotential of 388/490/570 mV in phosphate buffer solution) among non‐precious metal catalysts and even outperforms RuO2. Spectroscopic measurements and computational simulations revealed that the non‐3d metals modulate the electronic structure of Co for optimum reactant/product adsorption and tailor the energy of rate‐determining step to a more moderate value.
Open‐Shell 3d Transition Metal Nitridophosphates MIIP8N14 (MII=Fe, Co, Ni) by High‐Pressure Metathesis
Authors: Kloß Simon D. , Janka Oliver , Block Theresa , Pöttgen Rainer , Glaum Robert , Schnick Wolfgang 
Published: October 2018

Abstract3d transition metal nitridophosphates MIIP8N14 (MII=Fe, Co, Ni) were prepared by high‐pressure metathesis indicating that this route might give a systematic access to a structurally rich family of M‐P‐N compounds. Their structures, which are stable in air up to at least 1273 K, were determined through powder X‐ray diffraction and consist of highly condensed tetra‐layers of PN4 tetrahedra and MN6 octahedra. Magnetic measurements revealed paramagnetic behavior of CoP8N14 and NiP8N14 down to low temperatures while, FeP8N14 exhibits an antiferromagnetic transition at TN=3.5(1) K. Curie–Weiss fits of the paramagnetic regime indicate that the transition metal cations are in a oxidation state +II, which was corroborated by Mössbauer spectroscopy for FeP8N14. The ligand field exerted by the nitride ions in CoP8N14 and NiP8N14 was determined from UV/Vis/NIR data and is comparable to that of aqua‐ligands and oxophosphates.
The Chemical Properties of Hydrogen Atoms Adsorbed on M0‐Nanoparticles Suspended in Aqueous Solutions: The Case of Ag0‐NPs and Au0‐NPs Reduced by BD4−
Authors: Sermiagin Alina , Meyerstein Dan , Bar‐Ziv Ronen , Zidki Tomer 
Published: October 2018

AbstractThe nature of H‐atoms adsorbed on M0‐nanoparticles is of major importance in many catalyzed reduction processes. Using isotope labeling, we determined that hydrogen evolution from transient {(M0‐NP)‐Hn}n− proceeds mainly via the Heyrovsky mechanism when n is large (i.e., the hydrogens behave as hydrides) but mainly via the Tafel mechanism when n is small (i.e., the hydrogens behave as atoms). Additionally, the relative contributions of the two mechanisms differ considerably for M=Au and Ag. The results are analogous to those recently reported for the M0‐NP‐catalyzed de‐halogenation processes.
A Multi‐Ion Strategy towards Rechargeable Sodium‐Ion Full Batteries with High Working Voltage and Rate Capability
Authors: Jiang Chunlei , Fang Yue , Zhang Wenyong , Song Xiaohe , Lang Jihui , Shi Lei , Tang Yongbing 
Published: October 2018

AbstractSodium‐ion batteries (SIBs) are a promising alternative for the large‐scale energy storage owing to the natural abundance of sodium. However, the practical application of SIBs is still hindered by the low working voltage, poor rate performance, and insufficient cycling stability. A sodium‐ion based full battery using a multi‐ion design is now presented. The optimized full batteries delivered a high working voltage of about 4.0 V, which is the best result of reported sodium‐ion full batteries. Moreover, this multi‐ion battery exhibited good rate performance up to 30 C and a high capacity retention of 95 % over 500 cycles at 5 C. Although the electrochemical performance of this multi‐ion battery may be further enhanced via optimizing electrolyte and electrode materials for example, the results presented clearly indicate the feasibility of this multi‐ion strategy to improve the electrochemical performance of SIBs for possible energy storage applications.
Isolable Silylene Ligands Can Boost Efficiencies and Selectivities in Metal‐Mediated Catalysis
Authors: Zhou Yu‐Peng , Driess Matthias 
Published: October 2018

AbstractA significant number of isolable silylenes are currently known. They have quickly developed from laboratory curiosities to useful ligands in metal‐mediated homogeneous catalysis. This includes their utilization in various catalytic transformations, such as C−C cross‐coupling, cyclotrimerization, hydroformylation, borylation, deuteration, hydrosilylation, amination, hydrogenation, and transfer semi‐hydrogenation reactions. Recent studies suggest that the silylene ligands surpass the steering properties of their phosphine and N‐heterocyclic carbene (NHC) analogues and provide excellent chemo‐, regio‐, and stereoselectivites. Mechanistic studies suggest that their promoted performance of metal‐mediated catalytic transformations results from a strong σ‐donor character along with cooperative effects of their SiII centers. This Minireview covers the most recent advances in the field.
An Enantioconvergent and Concise Synthesis of Lasonolide A
Authors: Yang Lin , Lin Zuming , Shao Shunjie , Zhao Qian , Hong Ran 
Published: October 2018

AbstractEfficient access to medicinally significant natural products is an essential basis for the development of pharmaceuticals. The limited availability of marine natural products impedes broad biological evaluation. Despite several elegant syntheses of (−)‐lasonolide A having been reported, a practical synthesis of this potent anticancer polyketide remains elusive. Based on the application of borane as a traceless protecting group and the development of an unprecedented bissulfone reagent for Julia olefination, (−)‐lasonolide A was assembled in an enantioconvergent manner through the application of stereoselective hydroboration, allylation, and oxidation. This concise route may provide a realistic solution for accessing derivatives and analogues.
Enhancing the Efficacy of Photodynamic Therapy through a Porphyrin/POSS Alternating Copolymer
Authors: Jin Jianqiu , Zhu Yucheng , Zhang Zhenghe , Zhang Weian 
Published: October 2018

AbstractAggregation‐induced quenching (AIQ) of photosensitizers greatly reduces the quantum yield of singlet oxygen generation and mitigates the efficacy of photodynamic therapy (PDT). We have prepared an alternating copolymer starting from 4‐vinylbenzyl‐terminated tetraphenylporphyrin (VBTPP) and maleimide isobutyl polyhedral oligomeric silsesquioxane (MIPOSS), via alternating reversible addition–fragmentation chain transfer (RAFT) polymerization. Porphyrin and POSS are installed on the amphiphilic block copolymers backbone in an alternating fashion and POSS completely inhibits the aggregation of porphyrin units via stacking. The amphiphilic block copolymer can self‐assemble into nanoparticles and its application in PDT treatment was tested. These porphyrin‐containing polymeric nanoparticles display high photochemical yield and phototoxicity in vitro and in vivo, providing a novel strategy to enhance the PDT efficacy.
Effects of organomodified muscovite on the properties of acrylonitrile–butadiene–styrene nanocomposites
Authors: Che Ismail Nor Hafizah , Md. Akil Hazizan 
Published: October 2018

ABSTRACTIn this research, we investigated the mechanical and thermal properties of acrylonitrile–butadiene–styrene (ABS)–clay nanocomposites and correlated them with morphological characterizations. We prepared nanocomposites of ABS–clay by melt compounding in a Haake internal mixer. In this study, we investigated the influence of the ion‐exchange process and clay loading on the nanocomposite structure and characterized the nanocomposites with wide‐angle X‐ray diffraction (WAXD), transmission electron microscopy (TEM), contact angle measurement, field emission scanning electron microscopy (FESEM), tensile properties, hardness testing, and thermogravimetric analysis. The ABS–organomuscovite nanocomposites in this study displayed a higher tensile strength than ABS–muscovite. The modified muscovite indicated a 13% modulus elasticity in the ABS nanocomposites, whereas the elongation at break was detrimentally affected compared to that of the neat ABS. The WAXD and TEM results show the presence of mixed intercalated and exfoliated structures. FESEM analysis further revealed a good dispersion and interfacial adhesion of clay layers after subsequent modification. The contact angle measurements showed that the incorporation of organoclay was able to improve the hydrophobicity of the ABS nanocomposites. Finally, the hardness and thermal stability of the nanocomposites improved with the incorporation of modified muscovite. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46827.
Activation of Small Molecules by Compounds that Contain Triple Bonds Between Heavier Group‐14 Elements
Authors: Guo Jing‐Dong , Sasamori Takahiro 
Published: October 2018

AbstractDimetallynes (RE≡ER; E=Si, Ge, Sn, Pb), i.e., systems that contain triple bonds between heavier group‐14 elements represent the heavier homologues of alkynes. The high reactivity of disilynes, digermynes, distannynes, and diplumbynes can be interpreted in terms of their unique bonding situation, which includes a trans‐bent structure, a small HOMO–LUMO gap, a partial diradical character, their electronic nature, and interactions between bulky substituents. Relatively recent developments in the area of sterically demanding substituents have permitted isolating some stable compounds with a triple bond between heavier group‐14 elements. The structural features of these triple‐bonded compounds and their reactivity toward small molecules have been investigated using experimental and theoretical approaches. This review focuses on recent developments regarding the reactivity of stable compounds with a triple bond between heavier group‐14 elements toward small molecules, where the results were examined using quantum chemical methods. A comprehensive review on carbon chemistry is beyond the scope of this focus review.
Structure and Catalytic Mechanism of a Bacterial Friedel–Crafts Acylase
Authors: Pavkov‐Keller Tea , Schmidt Nina G. , Żądło‐Dobrowolska Anna , Kroutil Wolfgang , Gruber Karl 
Published: October 2018

AbstractC−C bond‐forming reactions are key transformations for setting up the carbon frameworks of organic compounds. In this context, Friedel–Crafts acylation is commonly used for the synthesis of aryl ketones, which are common motifs in many fine chemicals and natural products. A bacterial multicomponent acyltransferase from Pseudomonas protegens (PpATase) catalyzes such Friedel–Crafts C‐acylation of phenolic substrates in aqueous solution, reaching up to >99 % conversion without the need for CoA‐activated reagents. We determined X‐ray crystal structures of the native and ligand‐bound complexes. This multimeric enzyme consists of three subunits: PhlA, PhlB, and PhlC, arranged in a Phl(A2C2)2B4 composition. The structure of a reaction intermediate obtained from crystals soaked with the natural substrate 1‐(2,4,6‐trihydroxyphenyl)ethanone together with site‐directed mutagenesis studies revealed that only residues from the PhlC subunits are involved in the acyl transfer reaction, with Cys88 very likely playing a significant role during catalysis. These structural and mechanistic insights form the basis of further enzyme engineering efforts directed towards enhancing the substrate scope of this enzyme.