bluuebunny/crossref_metadata_2025 huggingface dataset:
Limiting the Uncoordinated N Species in M–Nx Single‐Atom Catalysts toward Electrocatalytic CO2 Reduction in Broad Voltage Range
Authors: Xi Dawei , Li Jiayi , Low Jingxiang , Mao Keke , Long Ran , Li Jiawei , Dai Zehui , Shao Tianyi , Zhong Yuan , Li Yu , Li Zibiao , Loh Xian Jun , Song Li , Ye Enyi , Xiong Yujie
Published: September 2021

Carbon‐supported single‐atom catalysts (SACs) are extensively studied because of their outstanding activity and selectivity toward a wide range of catalytic reactions. Amidst its development, excess dopants (e.g., nitrogen) are always required to ensure the high loading content of SACs on the carbon support. However, the use of excess dopants is accompanied by formation of miscellaneous structures (particularly the uncoordinated N species) on catalysts, leading to adverse effects on their performance. Herein, the synthesis of carbon‐supported Ni SACs with precisely controlled single‐atom structure via joule heating strategy, showing the coordination of 80% of N dopants with metal elements, is reported. The preclusion of the unfavorable N species is confirmed to be the main reason for the superior performance of optimized Ni SACs in electrocatalytic carbon dioxide reduction reaction, which demonstrates unprecedented activity, selectivity, and stability under an exceptionally broad voltage range (>92% CO selectivity in the range of −0.7 to −1.9 V reversible hydrogen electrode). Such a synthetic strategy is further applicable for the design of SACs with various metals. This work demonstrates a facile method for preclusion of unfavorable dopants in the SACs and its importance in catalytic application.
Interfacial Laser‐Induced Graphene Enabling High‐Performance Liquid−Solid Triboelectric Nanogenerator
Authors: Chen Yun , Xie Bin , Long Junyu , Kuang Yicheng , Chen Xin , Hou Maoxiang , Gao Jian , Zhou Shuang , Fan Bi , He Yunbo , Zhang Yuan‐Ting , Wong Ching‐Ping , Wang Zuankai , Zhao Ni
Published: September 2021

Laser‐induced graphene (LIG) has emerged as a promising and versatile method for high‐throughput graphene patterning; however, its full potential in creating complex structures and devices for practical applications is yet to be explored. In this study, an in‐situ growing LIG process that enables to pattern superhydrophobic fluorine‐doped graphene on fluorinated ethylene propylene (FEP)‐coated polyimide (PI) is demonstrated. This method leverages on distinct spectral responses of FEP and PI during laser excitation to generate the environment preferentially for LIG formation, eliminating the need for multistep processes and specific atmospheres. The structured and water‐repellant structures rendered by the spectral‐tuned interfacial LIG process are suitable as the electrode for the construction of a flexible droplet‐based electricity generator (DEG), which exhibits high power conversion efficiency, generating a peak power density of 47.5 W m−2 from the impact of a water droplet 105 µL from a height of 25 cm. Importantly, the device exhibits superior cyclability and operational stability under high humidity and various pH conditions. The facile process developed can be extended to realize various functional devices.
Controllable Solution‐Phase Epitaxial Growth of Q1D Sb2(S,Se)3/CdS Heterojunction Solar Cell with 9.2% Efficiency
Authors: Jin Xin , Fang Yanan , Salim Teddy , Feng Minjun , Yuan Zhengtian , Hadke Shreyash , Sum Tze Chien , Wong Lydia Helena
Published: September 2021

Antimony sulfoselenide (Sb2(S,Se)3) is a promising photoabsorber for stable and high efficiency thin film photovoltaics (PV). The unique quasi‐1D (Q1D) crystal structure gives Sb2(S,Se)3 intriguing anisotropic optoelectronic properties, which intrinsically require the optimization of crystal growth orientation, especially for electronic devices with vertical charge transport such as solar cells. Although the efficiency of Sb2(S,Se)3 solar cells has been improved greatly through optimizing the material quality, the fundamental issue of crystal orientation control in polycrystalline films remains unsolved, resulting in charge carrier recombination losses in the device. Herein, the epitaxial growth of vertically‐oriented Sb2(S,Se)3 film on hexagonal CdS is successfully realized via a solution‐based synergistic crystal growth process. The crystallographic orientation relationship between Sb2(S,Se)3 light absorber and the CdS substrate has been rigorously investigated. The best performing Sb2(S,Se)3 solar cell shows a high power conversion efficiency of 9.2% owing to the faster charge transport in the bulk and the efficient charge extraction across the heterojunction. This study points to a new direction to control the crystal growth of mixed‐anion Sb2(S,Se)3, which is crucial to achieve high efficiency solar cells based on antimony chalcogenides with low dimensionality.
Signal Filtering Enabled by Spike Voltage‐Dependent Plasticity in Metalloporphyrin‐Based Memristors
Authors: Wang Zhiyong , Wang Laiyuan , Wu Yiming , Bian Linyi , Nagai Masaru , Jv Ruolin , Xie Linghai , Ling Haifeng , Li Qi , Bian Hongyu , Yi Mingdong , Shi Naien , Liu Xiaogang , Huang Wei
Published: September 2021

Neural systems can selectively filter and memorize spatiotemporal information, thus enabling high‐efficient information processing. Emulating such an exquisite biological process in electronic devices is of fundamental importance for developing neuromorphic architectures with efficient in situ edge/parallel computing, and probabilistic inference. Here a novel multifunctional memristor is proposed and demonstrated based on metalloporphyrin/oxide hybrid heterojunction, in which the metalloporphyrin layer allows for dual electronic/ionic transport. Benefiting from the coordination‐assisted ionic diffusion, the device exhibits smooth, gradual conductive transitions. It is shown that the memristive characteristics of this hybrid system can be modulated by altering the metal center for desired metal–oxygen bonding energy and oxygen ions migration dynamics. The spike voltage‐dependent plasticity stemming from the local/extended movement of oxygen ions under low/high voltage is identified, which permits potentiation and depression under unipolar different positive voltages. As a proof‐of‐concept demonstration, memristive arrays are further built to emulate the signal filtering function of the biological visual system. This work demonstrates the ionic intelligence feature of metalloporphyrin and paves the way for implementing efficient neural‐signal analysis in neuromorphic hardware.
Doping Process of 2D Materials Based on the Selective Migration of Dopants to the Interface of Liquid Metals
Authors: Ghasemian Mohammad B. , Zavabeti Ali , Mousavi Maedehsadat , Murdoch Billy J. , Christofferson Andrew J. , Meftahi Nastaran , Tang Jianbo , Han Jialuo , Jalili Rouhollah , Allioux Francois‐Marie , Mayyas Mohannad , Chen Zibin , Elbourne Aaron , McConville Chris F. , Russo Salvy P. , Ringer Simon , Kalantar‐Zadeh Kourosh
Published: September 2021

The introduction of trace impurities within the doping processes of semiconductors is still a technological challenge for the electronics industries. By taking advantage of the selective enrichment of liquid metal interfaces, and harvesting the doped metal oxide semiconductor layers, the complexity of the process can be mitigated and a high degree of control over the outcomes can be achieved. Here, a mechanism of natural filtering for the preparation of doped 2D semiconducting sheets based on the different migration tendencies of metallic elements in the bulk competing for enriching the interfaces is proposed. As a model, liquid metal alloys with different weight ratios of Sn and Bi in the bulk are employed for harvesting Bi2O3‐doped SnO nanosheets. In this model, Sn shows a much stronger tendency than Bi to occupy surface sites of the Bi–Sn alloys, even at the very high concentrations of Bi in the bulk. This provides the opportunity for creating SnO 2D sheets with tightly controlled Bi2O3 dopants. By way of example, it is demonstrated how such nanosheets could be made selective to both reducing and oxidizing environmental gases. The process demonstrated here offers significant opportunities for future synthesis and fabrication processes in the electronics industries.
Micro‐Crack Assisted Wrinkled PEDOT: PSS to Detect and Distinguish Tensile Strain and Pressure Based on a Triboelectric Nanogenerator
Authors: Xiao Yu , Xu Yun , Qu Changming , Liu Hanyun , Zhang Shaochun , Lin Fangqi , Wu Weitong , Song Guofeng
Published: September 2021

The rapid advancements in wearable electronics are boosting the development of stretchable sensors. However, it is still a challenge to detect and distinguish multiple signals just using a single device. Here, a device made of micro‐crack assisted wrinkled poly(3,4‐ethylenedioxythiophene):poly(4‐styrenesulfonate) (PEDOT:PSS) is demonstrated, that can simultaneously detect and distinguish between tensile strain and pressure, based on the variation of resistance and single electrode mode triboelectric nanogenerator (S‐TENG). For the tensile strain sensing mode, the device, with εpre of 100% and micro‐cracks, shows a gauge factor (GF) of 1.75 with 40% linear tensile strain. For the S‐TENG based tactile sensing mode, this device has a superior pressure sensitivity of about 0.51 V N−1 in the pressure range of 0–24 N. This device demonstrates great stability and durability. By using two different methods, it can be applied on the human body to monitor the tensile strain and pressure without crosstalk. This work is promising for the development of wearable sensors and self‐powered electronics.
Recent Advances in Functional Bacterial Cellulose for Wearable Physical Sensing Applications
Authors: Huang Jieyu , Zhao Min , Hao Yi , Wei Qufu
Published: September 2021

Flexible physical sensors have attracted increasing attention due to their wide applications in human motion monitoring, human–machine interfaces, smart robots, and personalized medicine in recent years. As a natural biomass, bacterial cellulose (BC) plays an important role in the development of new generation sensors due to the low cost, renewability and biodegradability, 3D porous structure, mechanical flexibility, and robustness, which acts as a substrate, a reinforcing agent, and an active material in the forms of hydrogel, 3D aerogel, nanofiber dispersion, etc. Herein, three construction strategies of BC‐based functional sensing materials including in‐situ biosynthesized method, physical method, and chemical modification are briefly introduced. The focus then turns to the recent advances of functional BC for various sensing applications. Finally, an outlook of the future prospects for developing BC‐based functional sensing materials is presented.
Smart Refreshable Braille Display Device Based on Magneto‐Resistive Composite with Triple Shape Memory
Authors: Hu Tao , Xuan Shouhu , Gao Yinduan , Shu Quan , Xu Zhenbang , Sun Shuaishuai , Li Jun , Gong Xinglong
Published: September 2021

Braille devices made from stimuli‐active polymers have provided a new approach for obtaining information on Braille text. However, it is still essential to find a more convenient and effective method to develop multifunctional Braille devices with shape memory effects to broaden their applications. Here, a novel smart refreshable Braille display based on triple‐shape memory and magnetoresistive composite is developed with the advantages of simple fabrication, multifunctionality, and harmlessness for blind people. The triple shape memory effect enables this device to record the Braille text information and display the text using a complex Braille dot array. The stimuli‐dependent conductivity produces a simultaneous electrical sensing signal when Braille dots are touched, thus the reading areas can be distinguished. Therefore, this multifunctional flexible composite has the potential to realize a refreshable and portable Braille e‐book in the future.
Lithium Niobate on Insulator: An Emerging Platform for Integrated Quantum Photonics
Authors: Saravi Sina , Pertsch Thomas , Setzpfandt Frank
Published: September 2021

Due to its properties, lithium niobate is one of the most suitable material platforms for the implementation of integrated optical quantum circuits. With the commercialization of lithium niobate on insulator (LNOI) substrates in the recent years, the lithium niobate nanostructuring technology has progressed immensely. Now nanostructured LNOI components can be fabricated with a quality on par with any other material platform, and could act as effective building blocks for integrated quantum circuits. The advanced nanostructuring technology combined with its favorable material properties make the LNOI platform a real contender for the realization of large‐scale optical quantum circuits. The aim of this perspective article is to examine the utility of the LNOI platform toward this goal. To do this, first the availability of the individual components that can act as the building blocks for such circuits is investigated. Afterward, a fully on‐chip implementation of a multiplexed source of single photons on the LNOI platform is envisioned, which is a highly challenging task in all material platforms. Based on the performance of the state‐of‐the‐art components on the LNOI platform, the performance of such a device is quantified and the areas in which more progress is needed are pointed out.
Spectrometer‐free Optical Hydrogen Sensing Based on Fano‐like Spatial Distribution of Transmission in a Metal−Insulator−Metal Plasmonic Doppler Grating
Authors: Chen Yi‐Ju , Lin Fan‐Cheng , Singh Ankit Kumar , Ouyang Lei , Huang Jer‐Shing
Published: September 2021

Optical nanosensors are promising for hydrogen sensing because they are small, free from spark generation, and feasible for remote optical readout. Conventional optical nanosensors require broadband excitation and spectrometers, rendering the devices bulky and complex. An alternative is spatial intensity‐based optical sensing, which only requires an imaging system and a smartly designed platform to report the spatial distribution of analytical optical signals. Here, a spatial intensity‐based hydrogen sensing platform is presented based on Fano‐like spatial distribution of the transmission in a Pd‐Al2O3‐Au metal‐insulator‐metal plasmonic Doppler grating (MIM‐PDG). The MIM‐PDG manifests the Fano resonance as an asymmetric spatial transmission intensity profile. The absorption of hydrogen changes the spatial Fano‐like transmission profiles, which can be analyzed with a “spatial” Fano resonance model and the extracted Fano resonance parameters can be used to establish analytical calibration lines. While gratings sensitive to hydrogen absorption are suitable for hydrogen sensing, hydrogen insensitive gratings are also found, which provide an unperturbed reference signal and may find applications in nanophotonic devices that require a stable optical response under fluctuating hydrogen atmosphere. The MIM‐PDG platform is a spectrometer‐free and intensity‐based optical sensor that requires only an imaging system, making it promising for cellphone‐based optical sensing applications.
High Performance Inkjet‐Printed Quantum‐Dot Light‐Emitting Diodes with High Operational Stability
Authors: Jia Siqi , Tang Haodong , Ma Jingrui , Ding Shihao , Qu Xiangwei , Xu Bing , Wu Zhenghui , Li Guangyu , Liu Pai , Wang Kai , Sun Xiao Wei
Published: September 2021

Improving the stability of inkjet‐printed quantum dot light emitting diodes (QLEDs) is critical for the technology to become commercially viable. The major obstacle is the compromise between the printability of the ink system and the functionality of the carrier transport layers. Here, a ternary ink system consisting of octane, 1‐cyclohexyl‐ethanol, and n‐butyl acetate is reported, which solves the erosion between the printed quantum dot ink and the underneath hole transport layer. A gradient vacuum post‐treatment is developed to accompany the ternary ink system with gradient vacuum pressures, which is helpful in forming a uniform printing layer. Based on both technologies, the inkjet‐printed R/G/B QLEDS are fabricated with high resolution patterns, showing high efficiencies and stabilities. The external quantum efficiency of R/G/B devices is 19.3%, 18.0%, and 4.4%, respectively. Correspondingly, the half operating lifetime is up to 25 178 h @ 1000 cd m−2, 20 655 h @ 1000 cd m−2, and 46 h @ 100 cd m−2, respectively. The improvements in the ink engineering and post‐treatment in this study have taken the efficiency and stability of the devices to a higher level and confirm the application prospects of printed QLEDs in the display industry.
A Highly Efficient Eu2+ Excited Phosphor with Luminescence Tunable in Visible Range and Its Applications for Plant Growth
Authors: Kang Ziyong , Wang Shichuan , Seto Takatoshi , Wang Yuhua
Published: September 2021

A series of RbxK2−xCaPO4F:Eu2+ phosphors are synthesized using a high‐temperature solid‐phase method. An increase in the Rb+ concentration leads to the Eu2+‐excited phosphor emission spectra being shifted from red to cyan. Interestingly, the excitation spectrum does not exhibit any variations, which indicates the possibility of mixing the red (Rb0.2K1.8CaPO4F:Eu2+) and cyan (Rb2CaPO4F:Eu2+) phosphors for plant growth. This luminescence tuning is attributed to the substitution of K+ with Rb+, which produces an inferior crystal‐field splitting that increases the energy at the lowest 5d level, and enhances the rigidity of the crystal structure, which results in a gradual decrease in the Stokes shift and a consequent blue shift in the emission spectrum. Time‐resolved photoluminescence emission spectroscopy further confirms the occurrence of broadband emission owing to the occupation of multiple sites by Eu2+. Light‐emitting devices appropriate for plant growth are fabricated by mixing the two phosphors with a 380‐nm UV chip, and a light‐conversion film is prepared using the red phosphor and PDMS glue. The Chlorella‐based plant growth experiment reveals that the growth rate of Chlorella is 12.2% higher than that of the blank group, indicating the favorable effect of the light‐conversion film on plant growth.
Rapid Catalytic Water Disinfection from Earth Abundant Ca2Fe2O5 Brownmillerite
Authors: Vanags Mārtiņš , Mežule Linda , Spule Arnita , Kostjukovs Juris , Šmits Krišjānis , Tamm Aile , Juhna Talis , Vihodceva Svetlana , Käämbre Tanel , Baumane Larisa , Začs Dzintars , Vasiliev Grigory , Turks Maris , Mierina Inese , Sherrell Peter C. , Šutka Andris
Published: September 2021

Water disinfection is a crucial challenge for humanity. Approaches that are effective, cheap, environmentally friendly, and do not promote gene exchange between bacteria are urgently required. Strongly oxidizing radicals are highly promising to achieve this as they lead to bacterial activation at high efficiencies. However, sources to consistently generate these radicals are limited to high energy UV/H2O2 treatments requiring a large energy input. Here the use of abundant, cheap, brownmillerite (Ca2Fe2O5) is demonstrated as an efficient radical generation material under dark conditions, showing a seven order of magnitude decrease in bacterial concentration over 10 min. This decrease is attributed to the release of interlayer Ca2+ from the layered structure of Ca2Fe2O5 and hydroxyl radical generation. The efficacy of Ca2Fe2O5 is demonstrated by disinfecting turbid sewage sludge. The identification of this cheap, abundant, and nontoxic antibacterial material will provide an opportunity for broad scale clean water generation globally, and address the United Nations’ Sustainable Development Goal of clean water and sanitation.
The Journey of Water Remediation through Biomimetic Strategies: A Mechanistic Insight
Authors: Sen Gupta Ria , Padmavathy Nagarajan , Bose Suryasarathi
Published: September 2021

Nature‐driven designs for water crisis have shown much interest in energy‐efficient water treatment. This review discusses four different bioinspired systems, aquaporin membranes, mussel‐inspired amine‐based membranes, supramolecular architectures, and cactus/mangrove desalination. The authors have also delineated their contributions and mechanisms toward forming water pathways for effective desalination. The discussion is mainly channelized toward constructing generic approaches based on membranes with diverse shapes and dimensions, including hierarchically structured membranes. The separation properties of these bioinspired systems stem from their chemical and physical structures imparting selectivity in the separation of ions, pollutants, etc. Further, this review covers the practical methodologies for next‐generation energy‐efficient membranes and outlines the perspectives regarding the upcoming developments in water technology.
Positive Effect of Parasitic Monoclinic Phase of Hf0.5Zr0.5O2 on Ferroelectric Endurance
Authors: Song Tingfeng , Estandía Saúl , Tan Huan , Dix Nico , Gàzquez Jaume , Fina Ignasi , Sánchez Florencio
Published: September 2021

Endurance of ferroelectric HfO2 needs to be enhanced for its use in commercial memories. This work investigates fatigue in epitaxial Hf0.5Zr0.5O2 (HZO) instead of polycrystalline samples. Using different substrates, the relative amount of orthorhombic (ferroelectric) and monoclinic (paraelectric) phases is controlled. Epitaxial HZO films almost free of parasitic monoclinic phase suffer severe fatigue. In contrast, fatigue is mitigated in films with a greater amount of paraelectric phase. This suggests that fatigue can be intrinsically pronounced in ferroelectric HZO. It is argued that the enhancement of endurance in films showing coexisting phases results from the suppression of pinned domain propagation at ferroelectric–paraelectric grain boundaries, in contrast with a rapid increase of the size of the pinned domains in single ferroelectric regions.
Asymmetric Character of the Ferroelectric Phase Transition and Charged Domain Walls in a Hybrid Improper Ferroelectric
Authors: Weber Mads C. , Zemp Yannik , Trassin Morgan , Simonov Arkadiy , Schaab Jakob , Gao Bin , Cheong Sang‐Wook , Lottermoser Thomas , Fiebig Manfred
Published: September 2021

In improper ferroelectrics, the spontaneous ordering is typically driven by a structural distortion or a magnetic spin alignment. The induced electric polarization is only a secondary effect. This dependence is a rich source for unusual phenomena and ferroelectric domain configurations for proper, polarization‐driven ferroelectrics. This study focuses on the polar domain structure and the hysteretic behavior at the ferroelectric phase transition in Ca3Mn1.9Ti0.1O7 as a representative of the recently discovered hybrid improper ferroelectric class of multiferroics. Combining optical second harmonic generation and Raman spectroscopy gives access to the spontaneous structural distortion and the resulting improper electric polarization. This study shows that hybrid improper ferroelectrics contrast proper and improper ferroelectrics in several ways. Most intriguingly, adjacent ferroelectric domains favor head‐to‐head and tail‐to‐tail domain walls over charge‐neutral configurations. Furthermore, the phase transition occurs in an asymmetric fashion. The regime of phase coexistence of the nonpolar and polar phases shows a clear and abrupt upper temperature limit. In contrast, the coexistence toward low temperatures is best described as a fade‐out process, where 100‐nm‐sized islands of the nonpolar phase expand deep into the polar phase.
High‐Performance Self‐Powered Ultraviolet Photodetector based on Coupled Ferroelectric Depolarization Field and Heterojunction Built‐In Potential
Authors: Chen Jian , Wang Zihui , He Huanfeng , Mao Jiaxing , Zhang Ying , Zhang Qingfeng , Li Mingkai , Lu Yinmei , He Yunbin
Published: September 2021

Ferroelectric materials have aroused increasing interest in the field of self‐powered ultraviolet (UV) photodetectors for their polarization electric field induced photovoltaic (PV) effect. However, the device performance of currently reported ferroelectric‐based self‐powered UV detectors remains to be improved. Herein, achievement of high‐performance ZnO/Pb0.95La0.05Zr0.54Ti0.46O3 (PLZT) heterojunction‐based self‐powered UV photodetectors is demonstrated by coupling the ferroelectric depolarization electric field (Edp) and built‐in electric field (EZnO/PLZT) at the ZnO/PLZT interface with a II‐type energy band alignment. The ZnO/PLZT heterojunction‐based self‐powered UV photodetector shows a remarkable responsivity (R = 3.96 mA W−1) and detectivity (D* = 6.6 × 1010 Jones), which are by two orders of magnitude larger than those of the device that are produced under similar conditions without ZnO layer. Moreover, the ZnO/PLZT heterojunction‐based device exhibits a rapid response (rise time τr = 0.04 s, decay time τd = 0.05 s), which is faster than most of previous reports. The excellent device performance of the ZnO/PLZT heterojunction‐based device can be attributed to the efficient separation and transport of photogenerated carriers caused by the constructive coupling of Edp and EZnO/PLZT. This work offers a feasible and effective strategy for the performance improvement of ferroelectric‐based self‐powered UV detectors.
Dextran Sulfate Lithium as Versatile Binder to Stabilize High‐Voltage LiCoO2 to 4.6 V
Authors: Huang He , Li Zhiqiang , Gu Shuai , Bian Juncao , Li Yingzhi , Chen Jingjing , Liao Kemeng , Gan Qingmeng , Wang Yanfang , Wu Sisi , Wang Zhenyu , Luo Wen , Hao Rui , Wang Zhiqiang , Wang Guoyu , Lu Zhouguang
Published: September 2021

High‐voltage LiCoO2 is an attractive cathode for ultra‐high energy lithium‐ion batteries in the 5G era. However, the practical application of LiCoO2 is largely hindered by the unstable structure under high voltage. Herein, dextran sulfate lithium (DSL) is used as a versatile binder to improve the cycling stability of LiCoO2 at 4.6 V. A coulombic efficiency of almost 100% and 93.4% capacity retention after 100 cycles has been achieved. The aqueous DSL binder can be evenly coated onto the surfaces of LiCoO2 particles to function as an artificial interface, significantly preventing the decomposition of electrolyte and the dissolution of Co ions. More importantly, the superior interaction between the sulfate acid groups of DSL chains and the LiCoO2 particles enhances the stability of CoO chemical bonds, further suppressing the detrimental phase transition from O3 to H1‐3 above 4.55 V. The stabilization of high‐voltage LiCoO2 through the binder is facile and enlightening to design high energy battery materials.
Integrated Covalent Organic Framework/Carbon Nanotube Composite as Li‐Ion Positive Electrode with Ultra‐High Rate Performance
Authors: Gao Hui , Zhu Qiang , Neale Alex R. , Bahri Mounib , Wang Xue , Yang Haofan , Liu Lunjie , Clowes Rob , Browning Nigel D. , Sprick Reiner Sebastian , Little Marc A. , Hardwick Laurence J. , Cooper Andrew I.
Published: September 2021

Covalent organic frameworks (COFs) are promising electrode materials for Li‐ion batteries. However, the utilization of redox‐active sites embedded within COFs is often limited by the low intrinsic conductivities of bulk‐grown material, resulting in poor electrochemical performance. Here, a general strategy is developed to improve the energy storage capability of COF‐based electrodes by integrating COFs with carbon nanotubes (CNT). These COF composites feature an abundance of redox‐active 2,7‐diamino‐9,10‐phenanthrenequinone (DAPQ) based motifs, robust β‑ketoenamine linkages, and well‐defined mesopores. The composite materials (DAPQ‐COFX—where X = wt% of CNT) are prepared by in situ polycondensation and have tube‐type core‐shell structures with intimately grown COF layers on the CNT surface. This synergistic structural design enables superior electrochemical performance: DAPQ‐COF50 shows 95% utilization of redox‐active sites, long cycling stability (76% retention after 3000 cycles at 2000 mA g−1), and ultra‐high rate capability, with 58% capacity retention at 50 A g−1. This rate translates to charging times of ≈11 s (320 C), implying that DAPQ‐COF50 holds excellent promise for high‐power cells. Furthermore, the rate capability outperformed all previous reports for carbonyl‐containing organic electrodes by an order of magnitude; indeed, this power density and the rapid (dis)charge time are competitive with electrochemical capacitors.
Ion‐Conducting Channel Implanted Anode Matrix for All‐Solid‐State Batteries with High Rate Capability and Stable Anode/Solid Electrolyte Interface
Authors: Kim Chanho , Kim Jeongheon , Park Joonhyeok , Kim Jaeik , Lee Seungwoo , Sun Seho , Myung Seungchul , Lee Dongsoo , Park Keemin , Jang Inyoung , Kim Sungmin , Lee Hyungjun , Jung Hoyeon , Paik Ungyu , Song Taeseup
Published: September 2021

All‐solid‐state batteries (ASSBs) are expected to be next‐generation energy storage systems due to their high energy density and safety. However, their practical use has been limited by a poor rate capability caused by the Li dendrite growth. Under the operation with high current density, the Li migration rate at the interface between anode and solid electrolyte (SE) is faster than the Li replenishing rate by atom diffusion inside of Li, resulting in void formation at the interface between the anode and SE. These voids induce the increase in the localized current density, leading to the growth of Li dendrites. In this study, an ASSBs system is demonstrated with high rate capability by employing lithiated ZnO nanorods into Li. Lithiated ZnO nanorods, which are capable of Li‐ion conduction, providing the passage for Li transportation from the Li bulk to the interface between the Li and SE, resulting in an improvement in the replenishing rate. The lithiated ZnO nanorods in Li enable interfacial integrity by suppressing the void formation at the Li/SE interface even under the high current density. ASSBs employing Li with lithiated ZnO nanorods exhibit stable cyclability without short circuit at 0.3 C during 300 cycles and excellent rate capability.
Valuing impacts of proximity to Saguaro National Park on house prices
Authors: Mueller Julie M. , Loomis John B. , Richardson Leslie , Fitch Ryan A.
Published: September 2021

Proximity to public lands is well established within the literature as having a positive effect on nearby house prices. However, little research exists examining the impact of proximity to national parks. We use a hedonic property model with matching methods to estimate the value of proximity to Saguaro National Park West and Tucson Mountain Park. We find positive impacts of proximity to each park, with a larger aggregate effect from proximity to Saguaro National Park West. Our results provide useful insight into the potential impacts of changes in land use designation on nearby house prices.
A national assessment of residency wellness initiatives in emergency medicine
Authors: Parsons Melissa , Zuckerman Matthew , Twigg Sonia , Martínez Martínez Carmen J. , Gottlieb Michael
Published: September 2021

Background

Wellness is increasingly recognized as an important component of graduate medical education. However, there are limited data regarding how wellness initiatives are enacted in practice. This study aimed to survey emergency medicine (EM) residency programs to identify current, previous, and planned wellness initiatives as well as barriers to implementation and resources utilized.

Methods

This was a cross‐sectional survey study performed from November 2019 through January 2020. A literature search was performed to identify existing published wellness interventions and existing barriers, and these interventions and barriers were compiled to create a survey. The survey was piloted among five program directors and assistant program directors in person with feedback directly incorporated into the survey. The survey was sent to program leadership at all 223 Accreditation Council for Graduate Medical Education–accredited EM residency programs across the United States.

Results

Of the programs surveyed, 95 (42.6%) were included. The most common current wellness interventions reported were resident retreats (91%), group events (90%), formal mentorship (74%), and wellness committees (66%). Reported factors that contributed to the successful implementation of wellness interventions were faculty involvement (78%), resident involvement (78%), department chair support (51%), institutional support (44%), and financial support (36%). Lack of financial support (65%) and limited time (62%) were the most commonly reported barriers that prevented the implementation of wellness interventions.

Conclusions

Resident wellness is an important aspect of residency training. Survey respondents generally perceived that wellness interventions were associated with wellness improvement. Successful programs have financial, institutional, and chair support.
Stocking density effect on the growth and mortality of juvenile European flat oyster (Ostrea edulis Linnaeus, 1758)
Authors: Zorita Izaskun , Juez Ainhoa , Solaun Oihana , Muxika Iñigo , Rodríguez José Germán
Published: September 2021

The effect of stocking density on the growth and mortality of the European flat oyster (Ostrea edulis Linnaeus, 1758) reared in lantern nets was evaluated, starting from spat up to the end of juvenile phase. Oysters were deployed in a raft on the Basque coast (SE Bay of Biscay) for 18 months. Oysters were divided into four densities ranging from 25% to 100% of surface coverage. At the end of the experiment, oysters from an initial mean height and wet weight of 22.79 ± 3.70 mm and 1.00 ± 0.30 g reached mean values of 55.86 ± 8.21 mm and 19.08 ± 9.66 g, respectively. Although significant differences were detected in the growth of oysters reared at different stocking densities, these differences were not density dependent. On the other hand, mortality increased with time showing relatively high values (27%–38%), but especially at the end of the study when oysters at the highest density showed values up to 50%. In conclusion, stocking density had no effect on the growth, but had a negative effect on the survival at the highest density. A stocking density of 75% is recommended as the optimum for rearing O. edulis in the Basque coast.
High‐throughput computational screening of porous polymer networks for natural gas sweetening based on a neural network
Authors: Lu Xiuyang , Wu Yujing , Wu Xuanjun , Cao Zhixiang , Wei Xionghui , Cai Weiquan
Published: September 2021

The capture and storage of toxic industrial chemicals such as H2S using porous polymer networks (PPNs) has shown promising application because of their high porosity, high surface area, high stability, low‐cost and lightweight. In this work, 17,846 PPNs with the diamond‐like topology were computationally screened to identify the optimal adsorbents for the removal of H2S and CO2 from humid natural gas based on the combination of molecular simulation and machine learning algorithms. The top‐performing PPNs such as hPAFs‐0201 with the highest adsorption performance scores (APS) were evaluated and identified based on their adsorption capacities and selectivity for H2S and CO2. The strong affinity between water molecules and the framework atoms in a few PPNs has a significant impact on the adsorption selectivity of acid gases. Based on decision tree analysis, we found two main design paths of the optimal PPNs for natural gas sweetening, which are the PPNs with LCD ≤ 4.648 Å, Vf ≤ 0.035, and PLD ≤ 3.889 Å, and those with 4.648 Å ≤ LCD ≤ 5.959 Å, ρ ≤ 837 kg m−3. In addition, we constructed different machine learning models, particularly artificial neural network, available to accurately predict the APS of PPNs. 2D projection map of geometrical properties of PPNs using the t‐distributed stochastic neighbor embedding (t‐SNE) method shows that the screened 390 samples exhibit the similar structures. Among the top‐23 PPNs with the highest APS, hPAFs‐0201 has enhanced natural gas sweetening performance due to its strong affinity between the N‐rich organic linkers and acid gases. hPAFs‐0752 shows the highest isosteric adsorption heat of H2S and CO2 (Q°st = 49.84 kJ mol−1), resulting in its second‐highest APS as well as high hydrophilicity. Based on the combination of molecular simulation and machine learning, comprehensive insights into the high‐throughput screening of PPNs in this work will provide new ideas for the design of high‐performance PPNs for gas separation.
Artificial lift infrastructure planning of shale gas horizontal wells considering endogenous and exogenous uncertainties
Authors: Zeng Zuo , Cremaschi Selen
Published: September 2021

Artificial lift methods (ALMs) lift the accumulated fluids from horizontal shale‐gas‐producing wells and help sustain well performance. An artificial lift infrastructure plan includes the selection of ALMs and their operating schedule. This paper presents two discrete‐time large‐scale nonconvex mixed‐integer nonlinear programming models to solve the artificial lift infrastructure planning problem. Two equivalent mixed‐integer linear programming models are formulated using the special structure of the nonlinear terms. A set of valid inequalities is defined to tighten the models and shorten solution times to two orders of magnitude, considering well production limitations. We incorporate endogenous uncertainty in ALM‐dependent production rates and exogenous uncertainty in shale gas prices into the models. For a hypothetical case study under only endogenous uncertainties, the value of the stochastic solution is 5%. For the same case study, the exogenous uncertainty in gas prices does not change the optimum solution.
Smart Tactile Gloves for Haptic Interaction, Communication, and Rehabilitation
Authors: Ozioko Oliver , Dahiya Ravinder
Published: September 2021

Wearable human machine interfaces (HMI) such as smart gloves have attracted considerable interest in recent years. The quality of the interactive experience with the real and virtual world using wearable HMI technologies depends on the intuitive two‐way haptic interfaces they offer and the real‐time touch‐based information they send and receive. Herein, various smart glove solutions and their application in interaction, rehabilitation, virtual (VR) and augmented reality (AR), and augmentative and alternative communication (AAC) tasks are reviewed. While the early variants of such systems were based on commercial touch sensors and displays integrated (e.g., stitched) on wearables, electronic skin (e‐skin)‐type technologies with multifunctional capabilities are being explored nowadays for rich user experience and comfort. In this regard, instead of using separate touch sensors and actuators, miniaturized integrated devices providing both touch sensing and vibrotactile actuation have also been reported recently. Such advances, the associated challenges, and the advantages they offer for users to enjoy the full characteristic benefits of VR/ARs for interaction, immersion, and imagination are discussed. Finally, the huge potential the smart‐glove‐type solutions hold for advances in various application areas such as robotics, health care, sensorial augmentation for nondisabled and tactile Internet is also discussed.
Preparedness of Australasian emergency departments for point‐of‐care ultrasound in the COVID‐19 pandemic
Authors: Manivel Vijay , Herbert David G. , Kitson Gareth Ian , Robertson Dougal Buchanan , Basseal Jocelyne Marie , Manion James
Published: September 2021

Introduction

Point‐of‐care ultrasound (POCUS) has been brought to the limelight again, with a surge in lung ultrasound in suspected COVID‐19 patients. This is due to POCUS superiority over chest X‐ray, equivalent efficacy to computerised tomography chest for COVID‐19 diagnosis and potential minimisation of cross‐infection. However, inadequate disinfection practices could make ultrasound machines a vector for disease transmission. This study, conducted during the early phase of the COVID‐19 pandemic, surveyed the preparedness of Australasian Clinicians for responsible POCUS practice within the Emergency Department (ED).

Methods

An anonymous online survey conducted from 20th April to 3rd June 2020 among emergency clinicians providing POCUS within Australasian EDs investigated preparedness to provide effective POCUS while minimising cross‐infection.

Results

The survey received 171 responses and 116 being eligible for analysis. Most respondents (n = 96, 98%) had a separate ‘hot zone’ with a dedicated US device (n = 75, 77%), but lacked COVID‐19‐specific standard‐operating procedures (n = 51, 52%) or a designated safety and compliance officer (n = 36, 37%). Most clinicians (n = 86, 88%) were willing to perform ultrasound in highly infectious patients, despite poor formal training (n = 66, 67%) or COVID‐19‐specific lung protocols (n = 59, 60%). Most (n = 92, 93%) had access to appropriate low‐level disinfectant wipes but varied significantly in disinfection practice due to a lack of timely, formal or unified guidelines.

Conclusion

Australasian EDs significantly lacked investment in education, training and protocols to conduct safe POCUS in the COVID‐19 pandemic. A framework with evidence‐based, logistically feasible protocols supporting safe emergency POCUS is required to deal with similar future infectious outbreaks.
A Water‐Soluble Peptoid Chelator that Can Remove Cu2+ from Amyloid‐β Peptides and Stop the Formation of Reactive Oxygen Species Associated with Alzheimer's Disease
Authors: Behar Anastasia E. , Sabater Laurent , Baskin Maria , Hureau Christelle , Maayan Galia
Published: September 2021

Cu bound to amyloid‐β (Aβ) peptides can act as a catalyst for the formation of reactive oxygen species (ROS), leading to neuropathologic degradation associated with Alzheimer's disease (AD). An excellent therapeutic approach is to use a chelator that can selectively remove Cu from Cu–Aβ. This chelator should compete with Zn2+ ions (Zn) that are present in the synaptic cleft while forming a nontoxic Cu complex. Herein we describe P3, a water‐soluble peptidomimetic chelator that selectively removes Cu2+ from Cu–Aβ in the presence of Zn and prevent the formation of ROS even in a reductive environment. We demonstrate, based on extensive spectroscopic analysis, that although P3 extracts Zn from Cu,Zn–Aβ faster than it removes Cu, the formed Zn complexes are kinetic products that further dissociate, while CuP3 is formed as an exclusive stable thermodynamic product. Our unique findings, combined with the bioavailability of peptoids, make P3 an excellent drug candidate in the context of AD.
Remote Arylative Substitution of Alkenes Possessing an Acetoxy Group via β‐Acetoxy Elimination
Authors: Muto Kazuma , Kumagai Takaaki , Kakiuchi Fumitoshi , Kochi Takuya
Published: September 2021

Palladium‐catalyzed remote arylative substitution was achieved for the reaction of arylboronic acids with alkenes possessing a distant acetoxy group to provide arylation products having an alkene moiety at the remote position. The use of β‐acetoxy elimination as a key step in the catalytic cycle allowed for regioselective formation of unstabilized alkenes after chain walking. This reaction was applicable to various arylboronic acids as well as alkene substrates.
Nanoparticle‐Based Biosensing: En Route to Ultimate Sensitivity
Authors: Farka Zdeněk
Published: September 2021

Zdeněk Farka is an Assistant Professor at the Department of Biochemistry, Faculty of Science, Masaryk University (Czech Republic). He is a member of the Analysis & Sensing Early Career Advisory Board.
Acyl‐acyl carrier protein pool dynamics with oil accumulation in nitrogen‐deprived Chlamydomonas reinhardtii microalgal cells
Authors: Msanne Joseph , Vu Hieu Sy , Cahoon Edgar B.
Published: September 2021

Microalgae are potential biofuel feedstocks for production of energy‐dense triacylglycerols (TAG). Nitrogen deprivation is known to trigger microalgal TAG accumulation by upregulation of de novo fatty acid (FA) biosynthesis through chloroplast‐localized Type II FA synthases (FAS). To gain insights into the associated FAS regulatory mechanisms, we applied a recently reported liquid chromatography–mass spectrometry method to examine acyl‐acyl carrier protein (ACP) pool compositional changes of the microalga Chlamydomonas reinhardtii over a nitrogen deprivation time‐course. We observed that acyl‐ACP pools are highly enriched in acetyl‐ACP in nutrient‐rich media in photoheterotrophically grown cells. Following shift to nitrogen deprivation, acetyl‐ACP markedly decreased, and long‐chain palmitoyl (16:0)‐, stearoyl (18:0)‐, and oleoyl (18:1)‐ACPs progressively predominated in acyl‐ACP pools in parallel with increases in FA and TAG production. This study shows the utility of microalgal cells to study acyl‐ACP pool dynamics to gain insights into plant FA biosynthetic regulation and oil enhancement strategies.
Fabrication and characterization of dual layer PEBAX‐SiO2/polyethersulfone nanocomposite membranes for separation of CO2/CH4 gases
Authors: Barzegar Tahmineh , Hassanajili Shadi
Published: September 2021

A new method of fabricating thin film composite (TFC) membranes is presented through a one‐step co‐casting technique. In this method a dense layer of poly(ether‐block‐amide) (PEBAX‐1657) was formed on a porous support of polyethersulfone (PES) in one step by immersing the cast films in a coagulation bath of n‐hexane. To assess the impact of silica (SiO2) nanoparticles on characteristics of the fabricated membranes, dual‐layer nanocomposite membranes containing 2.5, 5, and 7.5 wt% of SiO2 nanoparticles in the dense layer were also prepared. Physical and mechanical properties of membranes were evaluated using scanning electron microscopy (SEM), Fourier transformed infrared spectroscopy, X‐ray diffraction, water contact angle and tensile strength measurements. SEM images revealed that a defect‐free top‐layer was formed on a porous substrate and both layers were adhered together properly. These images also showed that sub‐layer's microstructure was affected by addition of SiO2 nanoparticles to the PEBAX matrix. Gas permeation properties of membranes were recorded for pure CO2 and CH4 at room temperature and pressures in the range of 4–6 bars. Addition of SiO2 nanoparticles up to 5 wt% enhanced CO2/CH4 selectivity of the membranes, while at higher SiO2 nanoparticles loading (7.5 wt%), the selectivity was reduced.
Polystyrene‐poly(ethylene‐butylene)‐polystyrene/asphaltene sands composite elastomer with improved mechanical properties
Authors: Li Guo , Fan Guang‐Lin , Fan Ying‐Li , Jiang Jin‐Qiang , Shi Xian‐Ying , Liu Zhong‐Wen
Published: September 2021

Endowing polymers with improved mechanical properties by functional fillers is a continuously pursued topic. Although composites with different filler‐improved properties have been reported, the inevitably raised costs often restrict the practical uses of these products. Herein, we report the utilization of the waste asphaltene sands (AS) produced from the coal‐oil co‐processing process as a functional filler to toughen the thermoplastic elastomers represented by SEBS. The FT‐IR, XRD and elemental analysis showed that AS is a mixture consisting of organic compounds and inorganic minerals from the coal. After filling AS into SEBS, the inorganic minerals act as hard cores to strengthen the matrix while the surrounding aromatic and alkane compounds ensure a good compatibility of AS with SEBS. Composites with altered contents and sizes of AS particles were prepared by solvent processing and subsequent hot pressing. The optical microscopy images show a good dispersion of the AS particles in the SEBS substrate. As a result, the tensile strength of the composites are notably enhanced from 6.88 to 17.23 MPa after loading 20 wt% AS. Thus, the AS waste is very promising as the new and successful filler in developing polymers with improved mechanical properties and simultaneously reduced production cost.