bluuebunny/crossref_metadata_2025 huggingface dataset:
Crack Suppression in Conductive Film by Amyloid‐Like Protein Aggregation toward Flexible Device
Authors: Chen Mengmeng , Yang Facui , Chen Xi , Qin Rongrong , Pi Hemu , Zhou Guijiang , Yang Peng
Published: September 2021

A fatal weakness in flexible electronics is the mechanical fracture that occurs during repetitive fatigue deformation; thus, controlling the crack development of the conductive layer is of prime importance and has remained a great challenge until now. Herein, this issue is tackled by utilizing an amyloid/polysaccharide molecular composite as an interfacial binder. Sodium alginate (SA) can take part in amyloid‐like aggregation of the lysozyme, leading to the facile synthesis of a 2D protein/saccharide hybrid nanofilm over an ultralarge area (e.g., >400 cm2). The introduction of SA into amyloid‐like aggregates significantly enhances the mechanical strength of the hybrid nanofilm, which, with the help of amyloid‐mediated interfacial adhesion, effectively diminishes the microcracks in the hybrid nanofilm coating after repetitive bending or stretching. The microcrack‐free hybrid nanofilm then shows high interfacial activity to induce electroless deposition of metal in a Kelvin model on a substrate, which noticeably suppresses the formation of microcracks and consequent conductivity loss during the bending and stretching of the metal‐coated flexible substrates. This work underlines the significance of amyloid/polysaccharide nanocomposites in the design of interfacial binders for reliable flexible electronic devices and represents an important contribution to mimicking amyloid and polysaccharide‐based adhesive cements created by organisms.
Direct Chemical Vapor Deposition Synthesis of Porous Single‐Layer Graphene Membranes with High Gas Permeances and Selectivities
Authors: Yuan Zhe , He Guangwei , Faucher Samuel , Kuehne Matthias , Li Sylvia Xin , Blankschtein Daniel , Strano Michael S.
Published: September 2021

Single‐layer graphene containing molecular‐sized in‐plane pores is regarded as a promising membrane material for high‐performance gas separations due to its atomic thickness and low gas transport resistance. However, typical etching‐based pore generation methods cannot decouple pore nucleation and pore growth, resulting in a trade‐off between high areal pore density and high selectivity. In contrast, intrinsic pores in graphene formed during chemical vapor deposition are not created by etching. Therefore, intrinsically porous graphene can exhibit high pore density while maintaining its gas selectivity. In this work, the density of intrinsic graphene pores is systematically controlled for the first time, while appropriate pore sizes for gas sieving are precisely maintained. As a result, single‐layer graphene membranes with the highest H2/CH4 separation performances recorded to date (H2 permeance > 4000 GPU and H2/CH4 selectivity > 2000) are fabricated by manipulating growth temperature, precursor concentration, and non‐covalent decoration of the graphene surface. Moreover, it is identified that nanoscale molecular fouling of the graphene surface during gas separation where graphene pores are partially blocked by hydrocarbon contaminants under experimental conditions, controls both selectivity and temperature dependent permeance. Overall, the direct synthesis of porous single‐layer graphene exploits its tremendous potential as high‐performance gas‐sieving membranes.
A Bioinspired Stretchable Sensory‐Neuromorphic System
Authors: Kim Sun Hong , Baek Geun Woo , Yoon Jiyong , Seo Seunghwan , Park Jinhong , Hahm Donghyo , Chang Jun Hyuk , Seong Duhwan , Seo Hyunseon , Oh Seyong , Kim Kyunghwan , Jung Heeyoung , Oh Youngsu , Baac Hyoung Won , Alimkhanuly Batyrbek , Bae Wan Ki , Lee Seunghyun , Lee Minbaek , Kwak Jeonghun , Park Jin‐Hong , Son Donghee
Published: September 2021

Conventional stretchable electronics that adopt a wavy design, a neutral mechanical plane, and conformal contact between abiotic and biotic interfaces have exhibited diverse skin‐interfaced applications. Despite such remarkable progress, the evolution of intelligent skin prosthetics is challenged by the absence of the monolithic integration of neuromorphic constituents into individual sensing and actuating components. Herein, a bioinspired stretchable sensory‐neuromorphic system, comprising an artificial mechanoreceptor, artificial synapse, and epidermal photonic actuator is demonstrated; these three biomimetic functionalities correspond to a stretchable capacitive pressure sensor, a resistive random‐access memory, and a quantum dot light‐emitting diode, respectively. This system features a rigid‐island structure interconnected with a sinter‐free printable conductor, which is optimized by controlling the evaporation rate of solvent (≈160% stretchability and ≈18 550 S cm−1 conductivity). Devised design improves both areal density and structural reliability while avoiding the thermal degradation of heat‐sensitive stretchable electronic components. Moreover, even in the skin deformation range, the system accurately recognizes various patterned stimuli via an artificial neural network with training/inferencing functions. Therefore, the new bioinspired system is expected to be an important step toward implementing intelligent wearable electronics.
Abnormally High‐Lithium Storage in Pure Crystalline C60 Nanoparticles
Authors: Yin Linghong , Cho Jiung , Kim Su Jae , Jeon Il , Jeon Injun , Park Mihee , Park Minjoon , Jeong Se‐Young , Lee Dae Hyung , Seo Dong‐Hwa , Cho Chae‐Ryong
Published: September 2021

Li+ intercalates into a pure face‐centered‐cubic (fcc) C60 structure instead of being adsorbed on a single C60 molecule. This hinders the excess storage of Li ions in Li‐ion batteries, thereby limiting their applications. However, the associated electrochemical processes and mechanisms have not been investigated owing to the low electrochemical reactivity and poor crystallinity of the C60 powder. Herein, a facile method for synthesizing pure fcc C60 nanoparticles with uniform morphology and superior electrochemical performance in both half‐ and full‐cells is demonstrated using a 1 m LiPF6 solution in ethylene carbonate/diethyl carbonate (1:1 vol%) with 10% fluoroethylene carbonate. The specific capacity of the C60 nanoparticles during the second discharge reaches ≈750 mAh g−1 at 0.1 A g−1, approximately twice that of graphite. Moreover, by applying in situ X‐ray diffraction, high‐resolution transmission electron microscopy, and first‐principles calculations, an abnormally high Li storage in a crystalline C60 structure is proposed based on the vacant sites among the C60 molecules, Li clusters at different sites, and structural changes during the discharge/charge process. The fcc of C60 transforms tetragonal via orthorhombic LixC60 and back to the cubic phase during discharge. The presented results will facilitate the development of novel fullerene‐based anode materials for Li‐ion batteries.
Atomically Isolated Rh Sites within Highly Branched Rh2Sb Nanostructures Enhance Bifunctional Hydrogen Electrocatalysis
Authors: Zhang Ying , Li Gen , Zhao Zhonglong , Han Lili , Feng Yonggang , Liu Shangheng , Xu Bingyan , Liao Honggang , Lu Gang , Xin Huolin L. , Huang Xiaoqing
Published: September 2021

Breaking the bottleneck of hydrogen oxidation/evolution reactions (HOR/HER) in alkaline media is of tremendous importance for the development of anion exchange membrane fuel cells/water electrolyzers. Atomically dispersed active sites are known to exhibit excellent activity and selectivity toward diverse catalytic reactions. Here, a class of unique Rh2Sb nanocrystals with multiple nanobranches (denoted as Rh2Sb NBs) and atomically dispersed Rh sites are reported as promising electrocatalysts for alkaline HOR/HER. Rh2Sb NBs/C exhibits superior HER performance with a low overpotential and a small Tafel slope, outperforming both Rh NBs/C and commercial Pt/C. Significantly, Rh2Sb NBs show outstanding HOR performance of which the HOR specific activity and mass activity are about 9.9 and 10.1 times to those of Rh NBs/C, and about 4.2 and 3.7 times to those of Pt/C, respectively. Strikingly, Rh2Sb NBs can also exhibit excellent CO tolerance during HOR, whose activity can be largely maintained even at 100 ppm CO impurity. Density functional theory calculations reveal that the unsaturated Rh sites on Rh2Sb NBs surface are crucial for the enhanced alkaline HER and HOR activities. This work provides a unique catalyst design for efficient hydrogen electrocatalysis, which is critical for the development of alkaline fuel cells and beyond.
Femtosecond Laser Patterning Wettability‐Assisted PDMS for Fabrication of Flexible Silver Nanowires Electrodes
Authors: Liang Chang , Su Wenming , Sun Xiaoyan , Hu Youwang , Duan Ji'an
Published: September 2021

In this paper, a facile method is demonstrated to fabricate high resolution silver nanowires (AgNWs) electrode by combining femtosecond laser patterning and oxygen plasma treatment. The laser precision cutting selectively removes the thin polydimethylsiloxane (PDMS) mask to expose the target PDMS substrate. The subsequent oxygen plasma treatment makes the target substrate hydrophilic. The resulting wetting/dewetting pattern allows for selective trapping of AgNWs solutions into the hydrophilic regions. The geometry of AgNWs electrode can be readily tuned by varying the cutting path of laser patterning mask. Improving the cutting accuracy of mask by adjusting laser processing parameters, the minimum width of the AgNWs electrode can be reduced to 50 µm. The prepared AgNWs electrodes show good conductivity even after tensile strain less than 20% or 5000 bending cycles at 4 mm bending radius. Furthermore, using the patterned AgNWs electrodes, flexible electroluminescent displays are constructed, which exhibit bright and uniform emission with clear edges; even the track width is only 50 µm. This method provides a novel approach to pattern complex electrode for the application of flexible electronic products.
Thermoplasmonic Patterning of Silver Nanocrystal/Polymer Composite Thin Films
Authors: Prezgot Daniel , Bottomley Adam , Jorgenson Emma , Ianoul Anatoli
Published: September 2021

The lithographic patterning of polymer films is ubiquitous in manufacturing processes. In this work, the high photothermal conversion efficiency utilizes plasmonic nanoparticles to locally pattern polystyrene films. Silver nanocubes on polystyrene thin films are used as a heat source for photothermal lithographic patterning using a continuous‐wave, visible laser. Distinct states of the nanocomposite defined by their own far‐field optical properties and microscale topography are observed. At low intensities the nanocubes can be embedded into the polymer at a nanometer scale displacement precision and produce a notable shift in the distinct localized surface plasmon resonance, enabling two‐color optical patterning. Numerical modelling indicates the temperatures reached in the film surpass polystyrene's glass transition temperature (Tg, ≈90 °C). At higher laser intensities sufficient temperatures are reached to achieve pronounced polymer film displacement enabling direct‐write lithography. Temperature estimates highlight the role of collective contribution of nanoparticle heating in the process. The process can be controlled by selecting excitation wavelengths to tune the power absorbed by the nanocubes in accordance with their plasmonic absorption spectrum. The approach here outlines a general method of 2D optical patterning utilizing thermoplasmonics, which can be further expanded to other materials, applications, and potentially to subdiffraction length scales.
Novel Multifunctional Janus‐Type Membrane on Al Anode for Corrosion Protection
Authors: Wang Yue‐Feng , Yu Ying , Wang Jia‐Le , Peng Lai‐Hu , Zuo Yu‐Xin , Zuo Chun‐Cheng
Published: September 2021

Novel multifunctional Janus‐type membrane with both hydrophobic and anticorrosion abilities is constructed on the surface of aluminum (Al), using MoS2 as a hydrophobic layer and ZnO as a corrosion‐resistant layer. Al anode coated with the Janus‐type membrane is used as an example to study the specific property of the as‐prepared Janus‐type membrane. In the Al–air battery, the self‐corrosion of the Al anode is well inhibited since the Janus‐type membrane can block the invasion of excess hydroxide ions and water molecules simultaneously. The results show that the inhibition efficiency of the Janus‐type membrane is as high as 79.2%. Furthermore, the electrochemical measurements demonstrate that the discharge specific capacity of the Al–air battery with the Janus‐type membrane can reach up to 2095 mAh g−1, approximately two times as much as that of traditional batteries. The integrated strategy of combining hydrophobic and anticorrosion membrane is a novel method for corrosion protection of metal electrode. This Janus‐type membrane holds a great potential toward corrosion inhibition for the other metal in alkaline environment as well.
Inorganic Aqueous Anionic Redox Liquid Electrolyte for Supercapacitors
Authors: Pang Le , Wang Hongxia
Published: September 2021

Energy storage system based on supercapacitors is known for its high power density but suffers low energy density. To address this issue, aqueous anionic redox liquid electrolyte (AARLE) has been explored to enhance the energy density of supercapacitors by taking advantage of AARLE's favorable features including fast transport of ions in the liquid medium and electrochemical charge transfer of the redox couple in the liquid electrolyte, which is expected to produce supercapacitors with desirable high density of energy and power. The past few years have witnessed the progress of AARLE in energy storage applications such as supercapacitors. Given the significant potential of AARLE in supercapacitors, in this article, the application of AARLE in different types of supercapacitors, including electrical double‐layer capacitors, pseudocapacitors, and asymmetric supercapacitors is reviewed. The performance of the supercapacitors that utilize AARLE with representative redox couple species such as Br−/Br3−, I−/I3−, I2/IO3−, S2−/Sx2−, Fe(CN)64−/Fe(CN)63− is summarized and systematically analyzed in terms of specific capacitance, energy density, power density, and cycling stability. The underlying mechanism of these representative anionic redox species is shown in supercapacitors. The advantages and disadvantages of each of these anionic redox species are discussed regarding delivering stable supercapacitors with high energy density and power density for practical applications. Finally, the challenge and opportunity of AARLE for supercapacitors are presented. It is hoped that this timely review on this critical topic can offer a new perspective for developing high‐performance supercapacitors by taking advantage of the anionic redox charge storage in the liquid electrolytes in the future.
POSS Polyimide Sealed Flexible Triple‐Junction GaAs Thin‐Film Solar Cells for Space Applications
Authors: Qian Min , Mao Xiaojun , Wu Min , Cao Zhangyi , Liu Qing , Sun Lijie , Gao Yang , Xuan Xiaoyang , Pan Yu , Niu Yueping , Gong Shangqing
Published: September 2021

Flexibility and light weight are beneficial to reduce load, reduce volume, integrate device, and is the development trend of space science and technology. However, current solar cells on spacecrafts are still based on rigid triple‐junction GaAs solar cells covered by anti‐radiation glasses, which are heavy, non‐flexible, takes large separate space, and cannot be integrated with a spacecraft. To solve these problems, in this work, a transparent polyhedral oligomeric silsesquioxanes (POSS) polyimide film sealed flexible triple‐junction GaAs thin‐film solar cell has been developed by thermal lamination, with a high photoelectric conversion efficiency of 28.44% (AM0, 25°C) and stable performance upon a 4.1×1021atoms cm−2atomic oxygen exposure and an 89.5 ESH ultra‐violet exposure. Systematical space irradiations have been conducted to the transparent POSS polyimide sealing films by ground facilities in terms of atomic oxygen, ultra‐violet, electron, electron and proton, gamma ray, and thermal cycling. Fourier transform infrared spectroscopy, transmittance, mechanical tensile strength has been tested for exploring the mechanism of space environmental effects on transparent POSS polyimide film. This study suggests a transparent POSS polyimide sealed triple‐junction GaAs thin‐film solar cell with promising potentials in flexible, lightweight, integration for durable high‐efficiency power supplies in low and high Earth orbits.
Enzymatic Bioluminescence Modulation with an ATP Synthase Integrated Biotransducer
Authors: Chen Yukun , Cui Mingyin , Lin Chenliang , Liu Bingfu , Mitome Noriyo , Miyake Takeo
Published: September 2021

Ion carriers play an important role in biology in terms of control of a biological system, whereas electron carriers are key to engineered systems. Therefore, a biodevice requires an electron–ion coupling mechanism that can transmit an ion signal from a device to a biological system via an external voltage. In this study, a protonic biodevice is demonstrated that translates the proton signals from the device into an enzyme cascade by means of an ATP synthase and bioluminescent luciferase. The proton signals can be modulated through the applied potential to a sulfonated polyaniline biotransducer, with such protonic modulation controlling ATP synthesis at the ATP synthase membrane, followed by bioluminescence in the luciferin–luciferase reaction. The present electron–proton‐transportation platform provides a new means of controlling biological cascade reactions, with proton signals mediated by an external voltage.
Fingerprint‐Inspired High Conductive PEDOT‐Coated Nanofiber Film for Ultra‐Sensitive, Stretchable, and Flexible Piezoresistive Sensor
Authors: Fang Xiaohui , Zhao Shikun , Qin Zhen , Lv Yuhuan , Pan Kai
Published: September 2021

Flexible piezoresistive sensors are extensively applied in smart health monitoring systems due to their excellent shape adaptability, portability, and comfortableness. However, constructing piezoresistive sensors with both high sensitivities and wide pressure range remains a huge challenge. In this paper, inspired by the fingerprint structure, a 3D poly (3,4‐ethylenedioxythiophene) coated wrinkled nanofiber film based flexible piezoresistive sensor is developed through a simple method. Benefiting from the undulating structure of the conductive nanofiber film, there are abundant micro‐ridges on the surface of the rough nanofiber network, which make a significant contribution to the construction of new conductive paths under different pressures. This assembled sensor exhibits an ultra‐high sensitivity of 397.54 kPa−1 in a small pressure range (0–3 kPa) as well as an ultra‐wide pressure range of 0–25.48 kPa. In addition, it can maintain stable signal output even after 16 500 compression cycles. Furthermore, this high‐performance piezoresistive sensor is demonstrated to accurately identify the wrist pulse and joint bending of human body, which enables an extensive application prospect in the field of wearable electronics.
A Rapid Detection of COVID‐19 Viral RNA in Human Saliva Using Electrical Double Layer‐Gated Field‐Effect Transistor‐Based Biosensors
Authors: Paulose Akhil K. , Huang Chih‐Cheng , Chen Po‐Hsuan , Tripathi Adarsh , Chen Pin‐Hsuan , Huang Yu‐Shan , Wang Yu‐Lin
Published: September 2021

In light of the swift outspread and considerable mortality, coronavirus disease 2019 (COVID‐19) necessitates a rapid screening tool and a precise diagnosis. Saliva is considered as an alternative specimen to detect the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) since the viral load is comparable to what are found in a throat and a nasal cavity. The electrical double layer (EDL)‐gated field‐effect transistor‐based biosensor (BioFET) emerges as a promising candidate for salivary COVID‐19 tests due to a high sensitivity, a portable configuration, a label‐free operation, and a matrix insensitivity. In this work, the authors utilize EDL‐gated BioFETs to detect complementary DNAs (cDNAs) and viral RNAs with various testing conditions such as switches of probes, temperature treatments, and matrices. The selectivity is confirmed with cDNA and noncomplementary DNA (ncDNA), exhibiting an eightfold difference in electrical signals. The matrix insensitivity is evaluated, and BioFETs successfully validate the detection of SARS‐CoV‐2 N‐gene RNA down to 1 fm in diluted human saliva with a 95°C‐ and a 25°C‐treatment, respectively. This proposed system has a high potential to be deployed for an on‐site COVID‐19 screening, improving the disease control and benefitting frontline healthcare system.
Grain‐Specific Transitions Determine the Band Edge Luminescence in Dion–Jacobson Type 2D Perovskites
Authors: Kahmann Simon , Duim Herman , Rommens Alexander J. , Tekelenburg Eelco K. , Shao Shuyan , Loi Maria A.
Published: September 2021

The photophysics of 2D perovskites incorporating 1,4‐phenylenedimethanammonium (PDMA) as spacer cations is studied. PDMAPbI4 and PDMASnI4 exhibit absorption and luminescence spectra dominated by excitonic transitions and an emission due to two different states. Low‐temperature studies reveal a time‐dependent red shift of 12 meV that is correlated with grain‐specific luminescence spectra observed in optical micrographs. For the Pb‐variant, grains of red‐shifted and lower intensity band edge emission simultaneously exhibit a more pronounced luminescence from a broad defect‐related band around 2 eV. This suggests the grain‐specific emission to be related to local defects. These observations have important consequences for the understanding of luminescence of 2D perovskites, for which peak splitting of the band edge emission is a common, yet not completely resolved observation.
Photoionic Driven Movement of Metallic Ions as a Nonvolatile Reconfiguration Mechanism in Amorphous Chalcogenide Metasurfaces
Authors: McRae Liam , Xie Yunhui , Gholipour Behrad
Published: September 2021

Chalcogenide glasses have been widely adopted as a material platform for achieving reconfigurable metamaterials and metasurfaces, primarily through exploiting nonvolatile phase transitions inherent to these semiconductors. In such devices, the atomic lattice of the nanostructured medium reversibly changes between amorphous and crystalline phases, invoked through an energy‐intensive melt/quench process that can reduce device endurance due to chemical and geometrical drift. Metal‐doped amorphous chalcogenide semiconductors (MdACs) exhibit a directional photoinduced movement of their constituent metal‐ions when exposed to light with a photon energy equivalent or higher than the bandgap of the host chalcogenide glass. This “photoionic” movement results in nonvolatile changes of refractive index and conductivity at the nanoscale enabling a nonvolatile, nonbinary dynamic modulation of light removing the need for a phase transition. It is shown here that this photoionic movement in silver‐doped amorphous germanium selenide metasurfaces enables reversible optical switching. Understanding and integrating the photoionic mechanism within various optoelectronic device platforms presents significant potential for realizing a range of nonvolatile optically reconfigurable nanophotonic devices for emerging display, data storage, and signal processing applications.
Hybrid 2D‐QD MoS2–PbSe Quantum Dot Broadband Photodetectors with High‐Sensitivity and Room‐Temperature Operation at 2.5 µm
Authors: Kundu Biswajit , Özdemir Onur , Dalmases Mariona , Kumar Gaurav , Konstantatos Gerasimos
Published: September 2021

Broadband infrared photodetectors have profound importance in diverse applications including security, gas sensing, bioimaging, spectroscopy for food quality, and recycling, just to name a few. Yet, these applications can currently be served by expensive epitaxially grown photodetectors, limiting their market potential and social impact. The use of colloidal quantum dots (CQDs) and 2D materials in a hybrid layout is an attractive alternative to design low‐cost complementary metal‐oxide‐semiconductor (CMOS) compatible infrared photodetectors. However, the spectral sensitivity of these conventional hybrid detectors is restricted to 2.1 µm. Herein, a hybrid structure comprising molybdenum disulfide (MoS2) with lead selenide (PbSe) CQDs is presented to extend their sensitivity further toward the mid‐wave infrared, up to 3 µm. A room‐temperature responsivity of 137.6 A W−1 and a detectivity of 7.7 × 1010 Jones are achieved at 2.55 µm owing to highly efficient photoexcited carrier separation at the interface of MoS2 and PbSe in combination with an oxide coating to reduce dark current; the highest value is yet for a PbSe‐based hybrid device. These findings strongly support the successful fabrication of hybrid devices, which may pave the pathway for cost‐effective, high‐performance, next‐generation, novel photodetectors.
Recent Advances in Preparation and Applications of 3D Transition Metal Oxides Semiconductor Photonic Crystal
Authors: Yan Dan , Meng Zi-Hui , Qiu Li-Li , Xue Min
Published: September 2021

Nanostructured transition metal oxides (TMOs) semiconductor materials, whose photoelectric properties are significantly improved due to their nanostructures, have attracted more and more attention in recent years. As a functional material with periodic nanostructures and unique optical properties, photonic crystals (PhCs) have become an important option for nanostructuring semiconductor materials. The TMO semiconductor PhC (TMOPC), which is integrated by combining TMO with PhC, not only has the sensitivity of the TMO semiconductor to environmental stimulus, but also can improve the utilization rate of light and make the material have the optical response due to the optical modulation of PhC, such as slow light effect. The application of TMOPCs is widely promoted and expanded due to the improvement of its performance. Herein, this review summarizes the preparation methods of 3D TMOPCs in recent years and their main applications. The limitation and potential development of 3D TMOPCs in preparation and application are also discussed and prospected.
Application of Mutualism in Organic Synthetic Chemistry: Mutually Promoted C−H Functionalization of Indole and Reduction of Quinoline
Authors: Zhang Sutao , Xu Hai , He Jianghua , Zhang Yuetao
Published: September 2021

Here we reported a one‐pot, metal‐free B(C6F5)3‐catalyzed strategy for simultaneous synthesis of C3‐regioselective functionalization of indoles and complete reduction of quinolines. It turned out that by sharing a quinolinium hydridoborate intermediate, the original determining steps with high energy barrier in both the convergent disproportionation of indole and reduction of quinoline could be realized at room temperature, thus furnishing both the C3‐borylated (or silylated) indoles and N‐borylated tetrahydroquinolines in up to 98% yields at room temperature. Mechanistic studies suggested that both reactions would consume a product generated from the other reaction such that they can mutually promote each other, thus producing desirable products in a high atom‐economy and low energy‐cost manner. This strategy opened the gate to introducing mutualism to the field of chemistry.

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Clean Carbon Cycle via High‐Performing and Low‐Cost Solar‐Driven Production of Freshwater
Authors: Mazzone Valerio , Bonifazi Marcella , Aegerter Christof M. , Cruz Aluizio M. , Fratalocchi Andrea
Published: September 2021

While renewable power available worldwide costs increasingly less than the least expensive option based on fossil fuels, countries continue to increase their coal‐fired capacity, which should conversely fall by 80% within a decade to limit global warming effects. To address the challenges to the implementation of such an aim, here, a path is explored that leverages on a previously unrecognized aspect of coal, opening to a new solar‐driven carbon cycle that is environmentally friendly. By engineering the porosity matrix of coal into a suitably designed compressed volumetric structure, and by coupling it with a network of cotton fibers, it is possible to create a record performing device for freshwater production, with a desalination rate per raw material cost evaluated at 1.39 kg h $ at one sun intensity. This value is between two and three times higher than any other solar desalination device proposed to date. These results could envision a clean and socially sustainable cycle for carbon materials that, while enabling an enhanced water economy with global access to freshwater and sanitation, poses zero risks of reinjecting into the environment through competing economies in the fossil's market.
Enhancement Efficiency of Organic Photovoltaic Cells via Green Solvents and Nontoxic Halogen‐Free Additives
Authors: Fu Zhijie , Liu Xingpeng , Niu Xixi , Ren Meiling , Xue Luyang , Du Sanshan , Tong Junfeng , Li Jianfeng , Bao Xichang , Xia Yangjun
Published: September 2021

For organic photovoltaic cells, the development of new green solvents and nontoxic and halogen‐free additives is an urgent issue. Here, a simple combination of o‐xylene (O‐XY) and ethyl 2‐hydroxybenzoate (EHB) is introduced in inverted devices based on poly[4,8‐bis(5‐(2‐ethylhexyl)‐thiophene‐2‐yl) benzo[1,2‐b;4,5‐b′] dithiophene‐2,6‐diyl‐alt‐(4‐(2‐ethylhexyl)‐3‐fluorothieno[3,4‐b] thiophene)‐2‐carboxylate‐2‐6‐diyl]:[6,6]‐phenyl‐C71‐butyric acid methyl ester (PTB7‐Th:PC71BM) as blend layers, the device performance reaches optimal values (9.29%) when O‐XY and 3% EHB are introduced as additives, accompanied by the maximum fill factor (67.5%) and JSC (17.20 mA cm−2). From the results of characterization analysis, it is clear that EHB additive improves the crystallinity of the donor by regulating the kinetic process of active layer formation, selectively solubilizes the more aggregated fullerene acceptors, which allows PTB7‐Th to enter the conformational domain of PC71BM, and accelerates the molecular rearrangement. Besides, the EHB additive not only reduces the recombination, increases the carrier migration rate but also promotes the crystallinity of the donor, resulting in a tighter stacking. This work provides a green combination of solvents and additives that is important for the mass production of solar cells.
Biomimetic Wood‐Inspired Batteries: Fabrication, Electrochemical Performance, and Sustainability within a Circular Perspective
Authors: Gomez Iñaki , Lizundia Erlantz
Published: September 2021

Nature's hierarchical materials offer exceptional multifunctional properties thanks to their evolution over millions of years to reach the most optimized organization in terms of function, structure, or chemistry. Exploiting the unique features of natural materials through biomimicry offers an exciting research field with large potential for new discoveries. Wood, as one of the most fascinating biomaterials, combines unique mechanical properties, an anisotropic hierarchical porosity optimized to provide rapid, and low tortuosity pathways for nutrient/water transport, abundance, and biodegradability. Accordingly, wood has inspired scientists to mimic its outstanding properties in artificial analogues to develop batteries with remarkable electrochemical performance. For instance, its sophisticated structure can be transferred to solid‐state materials through biomimetic templating to increase the lifespan and energy density of batteries, while its inherent hierarchical multi‐channeled structure allows the synthesis of current collectors with enhanced ion and electron diffusivity. This Review highlights the recent progress into the application of wood as a hierarchically porous and renewable material to develop different battery components, including the cathode, the anode, the separator, and current collectors. The potential of wood‐inspired batteries to lessen the pressure over critical raw materials and additional environmental sustainability benefits are highlighted within a circular economy perspective.
Sulfonated Dopant‐Free Hole‐Transport Material Promotes Interfacial Charge Transfer Dynamics for Highly Stable Perovskite Solar Cells
Authors: Li Rui , Liu Maning , Matta Sri Kasi , Hiltunen Arto , Deng Zhifeng , Wang Cheng , Dai Zhicheng , Russo Salvy P. , Vivo Paola , Zhang Haichang
Published: September 2021

The integration of a functional group into dopant‐free hole‐transport materials (HTMs) to modify the perovskite|HTM interface has become a promising strategy for high‐performance and stable perovskite solar cells (PSCs). In this work, a sulfonated phenothiazine‐based HTM is reported, namely TAS, which consists of a butterfly structure with a readily synthesized N,​N‐​bis[4‐​(methylthio)​phenyl]​aniline side functional group. The interaction between TAS and perovskite via Pb–S bond induces a dipole moment that deepens the valence band of perovskite and thereby leads to enhanced open‐circuit voltage in corresponding n‐i‐p PSCs. More importantly, the functionalization of perovskite surface via Pb–S bond promotes the hole extraction reaction while suppressing the interfacial non‐radiative recombination, contributing to a 20–50% performance improvement compared to less‐ (4‐​(methylthio)​‐​N‐​[4‐​(methylthio)​phenyl]​aniline, DAS) or non‐interacting (N,N‐bis(4‐methoxyphenyl)aniline, TAO) counterparts. Consequently, TAS‐based PSCs exhibit superior device stability with a high PCE retention (>90% of the initial value) after 125 days of storage in the air.
Breaking Space Inversion‐Symmetry to Obtain Asymmetric Spin‐Wave Excitation in Systems with Nonuniform Magnetic Exchange
Authors: Macêdo Rair , Kudinoor Arjun S. , Livesey Karen L. , Camley Robert E.
Published: September 2021

The consequences of non‐uniform exchange in magnetic systems are reported. The quantum mechanical exchange interaction between spins is responsible for the phenomenon of magnetic order, and is generally considered to be uniform across bulk magnetic systems. Partly inspired by the Dzyaloshinskii‐Moriya interaction—also known as antisymmetric exchange—a linearly varying exchange interaction is used along a magnetic strip as a route to spatial inversion symmetry‐breaking. It is found that, in addition to asymmetric modes and localization, spatially varying exchange can be used to design nonreciprocal magnetic signal excitation at frequencies that are tunable. Moreover, the authors’ work predicts nonreciprocity to occur across a vast range of frequencies up to hundreds of GHz. Such spin wave engineering is a key area of ongoing research in the fields of magnonics and spintronics, which are expected to enable the next generation of wireless communication technology and information processing. Analogous nonreciprocity is expected to occur in other wave systems with gradient properties.
A Janovec‐Kay‐Dunn‐Like Behavior at Thickness Scaling in Ultra‐Thin Antiferroelectric ZrO2 Films
Authors: Tasneem Nujhat , Yousry Yasmin Mohamed , Tian Mengkun , Dopita Milan , Reyes‐Lillo Sebastian E. , Kacher Josh , Bassiri‐Gharb Nazanin , Khan Asif Islam
Published: September 2021

Originally based on phenomenological observations, the Janovec–Kay–Dunn (JKD) scaling law has been historically used to describe the dependence of the ferroelectric coercive fields (Ec) on a critical length scale of the material, wherein the film thickness (t) is considered the length scale, and Ec ∝ t−2/3. Here, for the first time, a JKD‐type scaling behavior is reported in an antiferroelectric material, using the ultra‐thin films of prototypical flourite‐structure binary oxide, zirconia. In these films, a decrease in the ZrO2 layer thickness from 20 nm to 5.4 nm leads to an increase in critical fields for both nonpolar‐to‐polar (Ea), and polar‐to‐nonpolar (Ef) transitions, accompanied by a decrease in the average crystallite size, and an increase in the tetragonal distortion of the non‐polar P42/nmc ground state structure. Notably, the ‐2/3 power law as in the JKD law holds when average crystallite size (d), measured from glancing‐incident X‐ray diffraction, is considered as the critical length scale—i.e., Ea, Ef ∝ d−2/3. First principles calculations suggest that the increase of tetragonality in thinner films contributes to an increase of the energy barrier for the transition from the non‐polar tetragonal ground state to the field‐induced polar orthorhombic phase, and in turn, an increase in Ea critical fields. These results suggest a de‐stabilization of the ferroelectric phase with a decreasing thickness in antiferroelectric ZrO2, which is contrary to the observations in its fluorite‐structure ferroelectric counterparts. With the recent interests in utilizing antiferroelectricity for advanced semiconductor applications, our fundamental exposition of the thickness dependence of functional responses therein can accelerate the development of miniaturized, antiferroelectric electronic memory elements for the complementary metal‐oxide‐semiconductor based high‐volume manufacturing platforms.
Ultrathin Polythiophene Films Prepared by Vertical Phase Separation for Highly Stretchable Organic Field‐Effect Transistors
Authors: Wang Xiaohong , Zhu Yingman , Liu Zhen , Yuan Ye , Qiu Longzhen
Published: September 2021

Physically blending semiconducting conjugated polymers with elastomeric materials and precisely controlling the resulting film structure provides an effective strategy to obtain intrinsically stretchable semiconducting polymers. Here, vertically phase‐separated ultrathin poly(3‐hexylthiophene) (P3HT) and polystyrene‐b‐polyisoprene‐b‐polystyrene (SIS) blend films are developed for one‐step fabrication of semiconductor and insulator layers of organic field effect transistors (OFETs). The phase‐separated structure, surface morphology, and tensile deformation are characterized by UV–vis absorption spectroscopy, atomic force microscopy, and optical microscopy. The blend film device maintains 43% of its mobility compared with 0.1% mobility of the pristine P3HT films after 50% stretch. The deformability of the films is efficiently improved by blending proved by both the finite element analysis and the dichroic ratio measurements. The P3HT/SIS blended films possess reproducible properties under 200 continuous stretch–release cycles at a strain of 50% without significantly reduced mobilities. The fully‐stretchable OFETs on polydimethylsiloxane substrate are also investigated and show a stretchability up to 70% and good electrical recovery properties after stretch–release process. The vertical phase‐separated structure obtained by the blends provides an effective way to easily fabricate stretchable devices with a balance between their mechanical and electrical properties.
Highly Reversible, Grain‐Directed Zinc Deposition in Aqueous Zinc Ion Batteries
Authors: Shin Jaeho , Lee Jimin , Kim Yangmoon , Park Youngbin , Kim Minkwan , Choi Jang Wook
Published: September 2021

Achieving highly reversible Zn metal anodes is a crucial step in advancing the performance of aqueous zinc ion batteries. However, despite the relative stability of Zn metal in aqueous environments, Zn metal is plagued by deterrents such as dendritic growth, H2 evolution, and corrosion. This mainly stems from the absence of a stable solid‐electrolyte interphase (SEI), an inevitable consequence of moderate concentration aqueous electrolytes. In response to such issues, herein, an artificial SEI formed from cross‐linked gelatin is introduced by coating the surface of Zn metal. The presence of the gelatin layer significantly changes the deposition morphology of Zn, where its plated surface is much more uniform and dense compared to bare Zn metal. Interestingly, grain‐directed electrodeposition can be observed in which the crystallographic orientation of the underlying Zn metal substrate determines the directionality of electrochemically plated Zn. This mode of growth results in a highly uniform and dense surface, translating to enhanced electrochemical stability.
A High‐Rate Electrode with Grotthuss Topochemistry for Membrane‐Free Decoupled Acid Water Electrolysis
Authors: Liang Shuaika , Jiang Miaomiao , Luo Hongxia , Ma Yuanyuan , Yang Jianping
Published: September 2021

Water electrolysis powered by renewable energies is regarded as the most promising technology for hydrogen production. However, in conventional acid water electrolysis, the H2 production and O2 production are tightly coupled and the proton exchange membrane is required to prevent the gases mixing, which reduce the flexibility of this technology and increase its cost. Here, a low‐cost hydrated Prussian blue analog (Turnbull's blue) electrode is introduced as a solid‐state redox mediator to decouple the acid water electrolysis into two steps without the use of membrane. The redox mediator shows high‐rate performance (42.7 mAh g−1 at 120 A g−1) and long cycle life (5000 cycles), which is owing to the diffusion‐free Grotthuss proton conduction. Moreover, this decoupled water electrolysis device facilitates the utilization of renewable energies for high‐purity hydrogen production at different spaces and times, which shows the high flexibility for H2 production.
ED EMS time: A COVID‐friendly alternative to ambulance ride‐alongs
Authors: Grawey Tom , Hinze Janice , Weston Benjamin
Published: September 2021

Background

Ambulance ride‐alongs are frequently a critical element of educational programs for learners of prehospital emergency care. We describe a novel alternative to the EMS ride‐along experience more conducive to COVID‐19 restrictions.

Methods

“ED EMS time” was developed as an alternative training method to provide a field‐type experience within the emergency department (ED) setting. Over the course of a 4‐h shift, medical students observe and complete standardized reflections on online medical control radio consultations and EMS‐to‐ED patient handoffs. Medical students also interview EMS clinicians to gain insight into prehospital care and the challenges that occur in the field. Experiences are debriefed with an EMS attending.

Results

Medical students expressed increased knowledge around the challenges and treatment capabilities of EMS through the ED EMS time experience. They were able to explain what information obtained from the scene was helpful to EMS clinicians. Medical students were able to realize the objectives of ambulance ride time through an ED experience designed around EMS.

Conclusions

ED EMS time represents a novel approach to teaching medical students the intricacies of prehospital medicine from the confines of the ED while avoiding direct patient contact, preserving PPE, and limiting COVID‐19 exposure.
Moving beyond personal factors: A national study of wellness interventions in emergency medicine residency programs
Authors: Li‐Sauerwine Simiao , Rebillot Katie , Chung Arlene S. , Coates Wendy C. , Shah Sneha , Yarris Lalena M.
Published: September 2021

Background

In 2017, the Accreditation Council for Graduate Medical Education (ACGME) revised its Common Program Requirements to support trainees and faculty by mandating programs to provide dedicated wellness resources and education. Emergency medicine may benefit from this change due to high burnout rates within the specialty. However, the current state of wellness interventions in emergency medicine (EM) residency programs has not yet been well described. Understanding current practices is necessary to assess unmet needs and inform the development and evaluation of future interventions that aim to improve trainee wellness.

Objectives

The goal of this study was to describe currently implemented wellness interventions in EM residency programs.

Methods

This descriptive study surveyed 250 ACGME‐accredited EM residency programs between March 1 and June 1, 2020, regarding wellness interventions. The survey included demographic questions; structured multiple‐choice questions about cost, frequency, and champions; and free‐text response options to briefly describe interventions. Respondents were also asked to classify the interventions according to the seven factors described in the National Academy of Medicine Model of Clinician Well‐Being and Resilience.

Results

Ninety of 250 (36% response rate) residency programs participated, describing 162 unique wellness interventions. Respondents classified the majority of interventions (n = 136) as targeting personal factors according to the National Academy of Medicine model. Qualitative analysis revealed five major themes describing the interventions: program culture, program factors, environmental and clinical factors, wellness activities and practices, and wellness resources.

Conclusions

Results of this survey may help to inform a national needs assessment addressing the current state of wellness interventions in EM residency programs. Our results highlight the need for more interventions targeting external factors impacting resident wellness.
Screening of heat‐tolerant Ethiopian chickpea accessions: Assessment of phenological and agromorphological traits and genomic relationships
Authors: Getahun Tsegaye , Negash Kassaye , Chang Peter L. , von Wettberg Eric , Carrasquilla‐Garcia Noelia , Gaur Pooran M. , Fikre Asnake , Haileslassie Teklehaimanot , Cook Douglas , Tesfaye Kassahun
Published: September 2021

A major agronomic challenge for chickpea (Cicer arietinum L.) production is temperatures above 35 °C, which causes reduced fertility and seed development. This study was aimed at assessing the phenotypic variation of chickpea genotypes under variable heat stress conditions. Chickpea genotypes were grown in heat‐stressed locations in both Ethiopia and India to assess phenotypic variation for heat tolerance. In addition, genomic relationships among the genotypes were assessed using genome‐wide single nucleotide polymorphism (SNP) markers. A total of 121 genotypes were assessed at three field sites in Ethiopia, under heat stress and nonstress conditions, and 57 genotypes were assessed under high‐heat‐stress conditions at the International Crops Research Institute for the Semiarid Tropics (ICRISAT) in Hyderabad, India. Data for five phenological and seven agromorphological traits were recorded. The results showed that the chickpea genotypes were severely affected by excessive heat at Hyderabad as compared with those planted under non‐heat‐stress conditions in Debre Zeit, Ethiopia. At extremely high temperatures, chickpea plants exhibited reduced floral initiation, arrested seed and pod development, shortened life cycles, and reduced plant height, seed size, grain yield, and yield‐related traits. Across stressed and nonstressed environments, there were highly significant differences among the genotypes for most of the traits (ANOVA, P ≤ .001). Under heat‐stressed environments, DZ‐Cr‐0034 was found to be a highly tolerant, whereas DZ‐Cr‐0026 was found to be a highly sensitive genotype. Genetic relationships among the genotypes were determined using 5,722 SNPs, revealing a single group of Ethiopian genotypes with small number of cultivars showing introgression from Middle Eastern germplasm. This study clearly demonstrated that there is genetic variability in chickpea for heat tolerance that can be harnessed to meet expected shifts towards warmer climatic conditions.