bluuebunny/crossref_metadata_2025_split huggingface dataset:
Excitations Partition into Two Distinct Populations in Bulk Perovskites
Authors: Wang Lili , Brawand Nicholas P. , Vörös Márton , Dahlberg Peter D. , Otto John P. , Williams Nicholas E. , Tiede David M. , Galli Giulia , Engel Gregory S. 
Published: January 2018

AbstractOrganolead halide perovskites convert optical excitations to charge carriers with remarkable efficiency in optoelectronic devices. Previous research predominantly documents dynamics in perovskite thin films; however, extensive disorder in this platform may obscure the observed carrier dynamics. Here, carrier dynamics in perovskite single‐domain single crystals is examined by performing transient absorption spectroscopy in a transmissive geometry. Two distinct sets of carrier populations that coexist at the same radiation fluence, but display different decay dynamics, are observed: one dominated by second‐order recombination and the other by third‐order recombination. Based on ab initio simulations, this observation is found to be most consistent with the hypothesis that free carriers and localized carriers coexist due to polaron formation. The calculations suggest that polarons will form in both CH3NH3PbBr3 and CH3NH3PbI3 crystals, but that they are more pronounced in CH3NH3PbBr3. Single‐crystal CH3NH3PbBr3 could represent the key to understanding the impact of polarons on the transport properties of perovskite optoelectronic devices.
Moiré Metamaterials and Metasurfaces
Authors: Wu Zilong , Zheng Yuebing 
Published: January 2018

AbstractOptical metamaterials and metasurfaces enable versatile light manipulations. Advancements in modeling, nanofabrication, and characterization tools have led to the development of metamaterials and metasurfaces for many applications: energy conversion, biomedicine, and information technology. Recently, metamaterials and metasurfaces with moiré configurations have attracted strong interest due to their highly tunable optical responses and high‐throughput fabrication. Herein, state‐of‐the‐art moiré metamaterials and metasurfaces are reviewed. The presentation covers fabrication techniques, structure–property relationships, and applications in lasing and biomedical sensing. The review concludes with challenges and opportunities for moiré metamaterials and metasurfaces.
Trapped‐Electron‐Induced Hole Injection in Perovskite Photodetector with Controllable Gain
Authors: Zhang Dezhong , Liu Chunyu , Li Kanzhe , Guo Wenbin , Gao Fengli , Zhou Jingran , Zhang Xindong , Ruan Shengping 
Published: January 2018

AbstractPerovskite is an excellent photosensitive material but it exhibits a shortcoming in providing photoconductive gain for layered photodetectors due to lacking of trap states. Here, the perovskite photodetectors are fabricated with controllable photoconductive gain by designing a trapped‐electron‐induced hole injection structure of [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM):2,3,5,6‐tetrafluoro‐7,7,8,8‐tetracyanoquinodimethane (F4‐TCNQ)/Bathocuproine/Au. The deep trap states provided by F4‐TCNQ can capture the photogenerated electrons from perovskite, which makes the hole injection barrier thin enough to be tunneled through, allowing the hole injection and forming a gain. Meanwhile, the gain is controllable by adjusting the electron trapping and hole transport capacities of PCBM:F4‐TCNQ dual‐functional layer, concomitantly realizing the transition of device from photovoltaic to photoconductive. Thus fabricated device achieves a higher external quantum efficiency of 6 × 104% at a lower bias of −1 V, and simultaneously maintains the rectifying behavior in dark, providing the detectivity of about 1 × 1015 Jones.
Single‐Shot Laser Additive Manufacturing of High Fill‐Factor Microlens Arrays
Authors: Surdo Salvatore , Carzino Riccardo , Diaspro Alberto , Duocastella Martí 
Published: January 2018

AbstractHigh fill‐factor microlens arrays (MLA) are key for improving photon collection efficiency in light‐sensitive devices. Although several techniques are now capable of producing high‐quality MLA, they can be limited in fill‐factor, precision, the range of suitable substrates, or the possibility to generate arbitrary arrays. Here, a novel additive direct‐write method for rapid and customized fabrication of high fill‐factor MLA over a variety of substrates is demonstrated. This approach uses a single laser pulse to delaminate and catapult a polymeric microdisc from a film onto a substrate of interest. Following a thermal reflow process, the printed disc can be converted into a planoconvex microlens offering excellent sphericity and high smoothness (RRMS < 40 Å). Importantly, the transfer of solid microdiscs enables fill‐factors close to 100%, not achievable with standard direct‐write methods such as inkjet printing or microdispensing. Arbitrary generation of MLA over flexible and curved surfaces, with microlenses presenting a curvature ranging from 20 to 240 µm and diffraction‐limited performance, is demonstrated. The ease of implementation and versatility of the approach, combined with its potential parallelization, paves the way for the high‐throughput fabrication of tailored MLA directly on top of functional devices.
Polarization Photoelectric Conversion in Layered GeS
Authors: Hsueh Hung‐Chung , Li Jia‐Xuan , Ho Ching‐Hwa 
Published: January 2018

AbstractPolarization photovoltaic effect is a unique character for an energy material with specific in‐plane anisotropy. Especially, if the energy material has a direct bandgap close to 1.6 eV, it will efficiently absorb full sunlight spectrum with specific axial polarization. In this study, polarized microtransmittance measurements of GeS multilayer with polarization angles ranging from θ = 0° (E || a) [through 90° (E || b)] to θ = 180° (E || a) have been studied near band edge. The polarized absorption edge follows a sinusoidal variation of E(θ) = 1.6 + 0.05⋅|sin(θ)| eV with respect to the angle change of the polarized absorption spectra. This anisotropic optical response is well reproduced by first‐principles calculations based on a combined Green's function technique, the GW–Bethe–Salpeter equation (BSE) approach. To characterize highly anisotropic band structure of layered GeS, polarized thermoreflectance measurement and first‐principles quasiparticle band‐structure calculations are also carried out. The interband transitions belonging to E ||a and E ||b polarizations are respectively identified. The polarized surface photovoltaic effects of a GeS Schottky solar cell are also tested. The special in‐plane optical anisotropy (along a and perpendicular to the a axis) renders GeS owning highly bi‐axial responsivity with respect to the c‐plane photoelectric conversion.
1D SbSeI, SbSI, and SbSBr With High Stability and Novel Properties for Microelectronic, Optoelectronic, and Thermoelectric Applications
Authors: Peng Bo , Xu Ke , Zhang Hao , Ning Zeyu , Shao Hezhu , Ni Gang , Li Jing , Zhu Yongyuan , Zhu Heyuan , Soukoulis Costas M. 
Published: January 2018

AbstractMechanical exfoliation of 2D materials has triggered an explosive interest in low dimensional material research. We extend this idea to 1D van der‐Waals materials. Three 1D semiconductors (SbSeI, SbSI, and SbSBr) with high stability and novel electronic properties are discovered using first principles calculations. Both the dynamical and the thermal stability of these 1D materials are examined. We demonstrate that their nanowire thinner than 7 Å can be easily obtained by mechanical exfoliation, hydrothermal method, or sonochemical method. The bulk‐to‐1D transition results in dramatic changes in band gap, effective mass, and static dielectric constant due to quantum confinement, making 1D SbSeI a highly promising channel material for transistors with gate length shorter than 1 nm. Under small uniaxial strain, these materials are transformed from indirect into direct band gap semiconductors, paving the way for optoelectronic devices and mechanical sensors. Moreover, the thermoelectric performance of these materials is significantly improved over their bulk counterparts. These highly desirable properties render SbSeI, SbSI, and SbSBr promising 1D materials for applications in future microelectronics, optoelectronics, mechanical sensors, and thermoelectrics.
Focused Ultrasound‐Augmented Delivery of Biodegradable Multifunctional Nanoplatforms for Imaging‐Guided Brain Tumor Treatment
Authors: Wu Meiying , Chen Wenting , Chen Yu , Zhang Haixian , Liu Chengbo , Deng Zhiting , Sheng Zonghai , Chen Jingqin , Liu Xin , Yan Fei , Zheng Hairong 
Published: January 2018

AbstractThe blood brain barrier is the main obstacle to delivering diagnostic and therapeutic agents to the diseased sites of brain. It is still of great challenge for the combined use of focused ultrasound (FUS) and theranostic nanotechnology to achieve noninvasive and localized delivery of chemotherapeutic drugs into orthotopic brain tumor. In this work, a unique theranostic nanoplatform for highly efficient photoacoustic imaging‐guided chemotherapy of brain tumor both in vitro and in vivo, which is based on the utilization of hollow mesoporous organosilica nanoparticles (HMONs) to integrate ultrasmall Cu2−xSe particles on the surface and doxorubicin inside the hollow interior, is synthesized. The developed multifunctional theranostic nanosystems exhibit tumor‐triggered programmed destruction due to the reducing microenvironment‐responsive cleavage of disulfide bonds that are incorporated into the framework of HMONs and linked between HMONs and Cu2−xSe, resulting in tumor‐specific biodegradation and on‐demand drug‐releasing behavior. Such tumor microenvironment‐responsive biodegradable and biocompatible theranostic nanosystems in combination with FUS provide a promising delivery nanoplatform with high performance for orthotopic brain tumor imaging and therapy.
Tin Selenide (SnSe): Growth, Properties, and Applications
Authors: Shi Weiran , Gao Minxuan , Wei Jinping , Gao Jianfeng , Fan Chenwei , Ashalley Eric , Li Handong , Wang Zhiming 
Published: January 2018

AbstractThe indirect bandgap semiconductor tin selenide (SnSe) has been a research hotspot in the thermoelectric fields since a ZT (figure of merit) value of 2.6 at 923 K in SnSe single crystals along the b‐axis is reported. SnSe has also been extensively studied in the photovoltaic (PV) application for its extraordinary advantages including excellent optoelectronic properties, absence of toxicity, cheap raw materials, and relative abundance. Moreover, the thermoelectric and optoelectronic properties of SnSe can be regulated by the structural transformation and appropriate doping. Here, the studies in SnSe research, from its evolution to till now, are reviewed. The growth, characterization, and recent developments in SnSe research are discussed. The most popular growth techniques that have been used to prepare SnSe materials are discussed in detail with their recent progress. Important phenomena in the growth of SnSe as well as the problems remaining for future study are discussed. The applications of SnSe in the PV fields, Li‐ion batteries, and other emerging fields are also discussed.
Recent Advances on Functionalized Upconversion Nanoparticles for Detection of Small Molecules and Ions in Biosystems
Authors: Gu Bin , Zhang Qichun 
Published: January 2018

AbstractSignificant progress on upconversion‐nanoparticle (UCNP)‐based probes is witnessed in recent years. Compared with traditional fluorescent probes (e.g., organic dyes, metal complexes, or inorganic quantum dots), UCNPs have many advantages such as non‐autofluorescence, high chemical stability, large light‐penetration depth, long lifetime, and less damage to samples. This article focuses on recent achievements in the usage of lanthanide‐doped UCNPs as efficient probes for biodetection since 2014. The mechanisms of upconversion as well as the luminescence resonance energy transfer process is introduced first, followed by a detailed summary on the recent researches of UCNP‐based biodetections including the detection of inorganic ions, gas molecules, reactive oxygen species, and thiols and hydrogen sulfide.
Recent Advances in Sensitized Photocathodes: From Molecular Dyes to Semiconducting Quantum Dots
Authors: Wu Hao‐Lin , Li Xu‐Bing , Tung Chen‐Ho , Wu Li‐Zhu 
Published: January 2018

AbstractThe increasing demand for sustainable and environmentally benign energy has stimulated intense research to establish highly efficient photo‐electrochemical (PEC) cells for direct solar‐to‐fuel conversion via water splitting. Light absorption, as the initial step of the catalytic process, is regarded as the foundation of establishing highly efficient PEC systems. To make full use of visible light, sensitization on photoelectrodes using either molecular dyes or semiconducting quantum dots provides a promising method. In this field, however, there remain many fundamental issues to be solved, which need in‐depth study. Here, fundamental knowledge of PEC systems is introduced to enable readers a better understanding of this field. Then, the development history and current state in both molecular dye‐ and quantum dot‐sensitized photocathodes for PEC water splitting are discussed. A systematical comparison between the two systems has been made. Special emphasis is placed on the research of quantum dot‐sensitized photocathodes, which have shown superiority in both efficiency and durability towards PEC water splitting at the present stage. Finally, the opportunities and challenges in the future for sensitized PEC water‐splitting systems are proposed.
Si‐Doped Cu(In,Ga)Se2 Photovoltaic Devices with Energy Conversion Efficiencies Exceeding 16.5% without a Buffer Layer
Authors: Ishizuka Shogo , Nishinaga Jiro , Iioka Masayuki , Higuchi Hirofumi , Kamikawa Yukiko , Koida Takashi , Shibata Hajime , Fons Paul 
Published: January 2018

AbstractIn this communication, novel and simplified structure Cu(In,Ga)Se2 (CIGS) solar cells, which nominally consist of only a CIGS photoabsorber layer sandwiched between back and front contact layers but yet demonstrate high photovoltaic efficiencies, are reported. To realize this accomplishment, Si‐doped CIGS films grown by the three‐stage coevaporation method, B‐doped ZnO transparent conductive oxide front contact layers deposited by chemical vapor deposition, and heat–light soaking treatments are used. Si‐doping of CIGS films is found to modify the film surfaces and grain boundary properties and also affect the alkali metal distribution profiles in CIGS films. These effects are expected to contribute to improvements in buffer‐free CIGS device performance. Heat–light soaking treatments, which are occasionally performed to improve conventional buffer‐based CIGS device performance, are found to be also effective in enhancing buffer‐free CIGS photovoltaic efficiencies. This result suggests that the mechanism behind the beneficial effects of heat–light soaking treatments originates from CIGS bulk issues and is independent of the buffer materials. Consequently, over 16.5% efficiencies, including an independently certified value, are demonstrated from completely buffer‐free CIGS photovoltaic devices.
Less is More: Dopant‐Free Hole Transporting Materials for High‐Efficiency Perovskite Solar Cells
Authors: Zhou Weiqi , Wen Zhenhai , Gao Peng 
Published: January 2018

AbstractPerovskite solar cells have delivered power conversion efficiency beyond 22% in less than seven years, implying the potential for the paradigm shift of low‐cost photovoltaics with high efficiency and low embedded energy. Besides the “perovskite fever,” the development of new hole transport materials (HTM), especially dopant‐free HTMs, is another research hotspot. This is because the currently used HTMs, such as spiro‐OMeTAD derivatives, require additional chemical doping process to ensure sufficient conductivity and proper ionic potential level for efficient hole transport and collection. However, the commonly used dopants are volatile and hygroscopic which not only increase the complexity and cost of device fabrication but also deteriorate the device stability. So far, there have been several reviews on new HTMs, but review or analysis on dopant‐free HTMs is scarce. In this review, all reported dopant‐free HTMs are categorized into four primary different types and lessons will be learned during the separate discussions. The stability test behavior of all the intrinsic HTMs will be evaluated directly. In the end, the correlations between the properties of the intrinsic HTMs and parameters of the devices will be plotted to shed light on the future direction of development of this field.
A Biobased Composite Gel Polymer Electrolyte with Functions of Lithium Dendrites Suppressing and Manganese Ions Trapping
Authors: Zhu Ming , Wu Jiaxin , Zhong Wei‐Hong , Lan Jinle , Sui Gang , Yang Xiaoping 
Published: January 2018

AbstractLithium (Li) dendrites in Li anodes, and dissolution and migration of manganese (Mn) ions in LiMn2O4 (LMO) cathodes, have hampered these extraordinary electrode materials from being efficiently applied in high performance Li batteries. Here, a novel, bifunctional, biobased composite gel polymer electrolyte (c‐GPE) is created to simultaneously deal with the two critical issues. The skeleton of c‐GPE is constructed from a sandwich structure composed of porous polydopamine spheres and two layers of the environmentally friendly soy protein isolate‐based nanofiber membranes, and the carbonized polydopamine spheres are coated without any binder on the surface of the membranes. After a facile and innocuous preparation process, the skeleton material displays excellent thermal stability and good affinity to liquid electrolyte, which endows c‐GPE with significant functions of effective mitigation of the dissolution of Mn ions, and chelation of the fleeing Mn ions, as well as the dramatic suppression of Li dendrite growth. Consequently, the LMO/Li batteries involving c‐GPE show a great improvement in the cycling stability and rate performance compared with those of the cells based on commercial Celgard 2400. This work will be quite promising to meet the distinct requirements from Li batteries and provide a high‐efficiency and safe biobased GPE for next generation energy storage systems.
Sustainable and Efficient CuI‐NPs‐Catalyzed Cross‐Coupling Approach for the Synthesis of Tertiary 3‐Aminopropenoates, Triazoles, and Ciprofloxacin
Authors: Nayal Onkar S. , Thakur Maheshwar S. , Kumar Manoranjan , Shaifali  , Upadhyay Rahul , Maurya Sushil K. 
Published: January 2018

AbstractThe unique properties of metal nanoparticles have attracted significant attention from synthetic chemists, notably for application in heterogeneous catalysis. Herein, we report a highly efficient, sustainable, and atom‐economical approach for the synthesis of tertiary 3‐aminopropenoates from alkynes and secondary amines by using heterogeneous copper(I) iodide nanoparticles (CuI NPs) as a catalyst. The broad utility of this strategy is demonstrated by the synthesis of a wide range of tertiary 3‐aminopropenoates. The value of this transformation has been highlighted by the synthesis of biologically active ciprofloxacin and its derivatives on a gram scale. This method was also applied to the synthesis of 1,4‐disubstituted 1,2,3‐triazoles.
Asthma onset pattern and patient outcomes in a chronic rhinosinusitis population
Authors: John Staniorski Christopher , Price Caroline P.E. , Weibman Ava R. , Welch Kevin C. , Conley David B. , Shintani‐Smith Stephanie , Stevens Whitney W. , Peters Anju T. , Grammer Leslie , Lidder Alcina K. , Schleimer Robert P. , Kern Robert C. , Tan Bruce K. 
Published: January 2018

BackgroundChronic rhinosinusitis (CRS) is strongly associated with comorbid asthma. This study compares early‐onset and late‐onset asthma in a CRS population using patient‐reported and clinical characteristics.MethodsAt enrollment into a clinical registry, CRS patients completed the 22‐item Sino‐Nasal Outcome Test (SNOT‐22), Asthma Control Test (ACT), mini‐Asthma Quality of Life Questionnaire (miniAQLQ), the 29‐item Patient‐Reported Outcomes Measurement Information System (PROMIS‐29), and medication use questionnaires. Patients also reported comorbid asthma and age at first asthma diagnosis. Early‐onset (<18 years) and late‐onset (>18 years) asthma groups were defined. Analysis of variance (ANOVA), chi‐square, and Kruskal‐Wallis tests were used to compare patient responses.ResultsA total of 199 non‐asthmatic (56.1%), 71 early‐onset asthmatic (20.0%), and 85 late‐onset asthmatic (23.9%) CRS patients completed the survey. Body mass index (BMI) was significantly higher in late‐onset asthmatic (p = 0.046) while age, gender, race, and smoking history did not differ with time of asthma onset. SNOT‐22, ACT, and miniAQLQ were not different between asthma groups, but late‐onset asthmatics had significantly lower physical function than non‐asthmatics (p = 0.008). Compared to non‐asthmatics, late‐onset asthmatics showed increased rates of nasal polyps (p < 0.001), higher Lund‐Mackay scores (p = 0.005), and had received more oral steroid courses (p < 0.001) and endoscopic surgeries (p = 0.008) for CRS management. Late‐onset asthmatics compared to early‐onset asthmatics showed increased nasal polyposis (p = 0.011) and oral steroid courses for CRS (p = 0.003).ConclusionWhile CRS‐specific and asthma‐specific patient‐reported outcome measures (PROMs) were not significantly different among groups, CRS patients with late‐onset asthma had poorer physical function, more frequent nasal polyposis, and required increased treatment for CRS. Late‐onset asthma may predict more severe disease in CRS.
Vom Design der Moleküle des Lebens zum Design von Leben: Zukünftige Anwendungen von DNA‐Technologien
Authors: Kohman Richie E. , Kunjapur Aditya M. , Hysolli Eriona , Wang Yu , Church George M. 
Published: January 2018

AbstractSeit der Aufklärung ihrer Struktur steht die DNA im Zentrum der biologischen Forschung. In den letzten 50 Jahren ist die Entwicklung von DNA‐Technologien rasant vorangeschritten, insbesondere im Bereich der DNA‐Sequenzierung. Parallel dazu wurden auch gewaltige Fortschritte in der DNA‐Synthese und DNA‐Editierung erzielt, die sich von der Oligonukleotid‐ bis zur Genom‐Ebene erstrecken. In diesem Aufsatz erörtern wir vier verschiedene Teilbereiche von DNA‐Technologien und folgen dabei diesem Verlauf von kleinerem zu größerem Maßstab. Wir beginnen mit dem Aufbau von Materialien aus DNA, die wiederum als Transportsysteme in vivo dienen können. Anschließend diskutieren wir, wie die Modifizierung mikrobieller Genome zu neuartigen Methoden für die Produktion industrieller Biologika führen kann. Als nächstes reden wir über die Zukunft der Genomsynthese als eine Methode für die Evolutionsforschung. Schließlich erläutern wir, wie das Barcoding biologischer Systeme deren dreidimensionale Analyse in hoch parallelisierter Weise ermöglicht.
C8N26H4: An Environmentally Friendly Primary Explosive with High Heat of Formation
Authors: Chen Dan , Yang Hongwei , Yi Zhenxin , Xiong Hualin , Zhang Lin , Zhu Shunguan , Cheng Guangbin 
Published: January 2018

AbstractThe synthesis and characterization of the metal‐free polyazido compounds 3,6‐bis‐(2‐(4,6‐diazido‐1,3,5‐triazin‐2‐yl)‐hydrazinyl)‐1,2,4,5‐tetrazine (2) and 3,6‐bis‐(2‐(4,6‐diazido‐1,3,5‐triazin‐2‐yl)‐diazenyl)‐1,2,4,5‐tetrazine (4) are presented. Two compounds were characterized by NMR spectra, IR spectroscopy, mass spectrometry, and differential scanning calorimetry (DSC). Additionally, the structure of 2 was confirmed by single‐crystal X‐ray diffraction. Compounds 2 and 4 exhibit measured densities (1.755 g cm−3 and 1.763 g cm−3), good thermal stabilities (194 °C and 189 °C), high heat of formation (2114 kJ mol−1 and 2820 kJ mol−1), and excellent detonation performance (D, 8365 m s−1 and 8602 m s−1; P, 26.8 GPa and 29.4 GPa). Furthermore, compounds 2 and 4 have been tested for their priming ability to detonate RDX. The results indicate that the title compound 2 is a potential environmentally friendly alternative candidate to lead‐based primary explosives.