bluuebunny/crossref_metadata_2025 huggingface dataset:
Bright and Efficient Light‐Emitting Devices Based on 2D Transition Metal Dichalcogenides
Authors: Ahmed Tanveer , Zha Jiajia , Lin Kris KH , Kuo Hao‐Chung , Tan Chaoliang , Lien Der‐Hsien
Published: February 2023

2D monolayer transition metal dichalcogenides (TMDCs) show great promise for the development of next‐generation light‐emitting devices owing to their unique electronic and optoelectronic properties. The dangling‐bond‐free surface and direct‐bandgap structure of monolayer TMDCs allow for near‐unity photoluminescence quantum efficiencies. The excellent mechanical and optical characteristics of 2D TMDCs offer great potential to fabricate TMDC‐based light‐emitting diodes (LEDs) featuring good flexibility and transparency. Great progress has been made in the fabrication of bright and efficient LEDs with varying device structures. In this review, the aim is to provide a comprehensive summary of the state‐of‐the‐art progress made in the construction of bright and efficient LEDs based on 2D TMDCs. After a brief introduction to the research background, the preparation of 2D TMDCs used for LEDs is briefly discussed. The requirements and the corresponding challenges to achieve bright and efficient LEDs based on 2D TMDCs are introduced. Thereafter, various strategies to enhance the brightness of monolayer 2D TMDCs are described. Following that, the carrier‐injection schemes enabling bright and efficient TMDC‐based LEDs along with the device performance are summarized. Finally, the challenges and future prospects regarding the accomplishment of TMDC‐LEDs with ultimate brightness and efficiency are discussed.
Jellybean Quantum Dots in Silicon for Qubit Coupling and On‐Chip Quantum Chemistry
Authors: Wang Zeheng , Feng MengKe , Serrano Santiago , Gilbert William , Leon Ross C. C. , Tanttu Tuomo , Mai Philip , Liang Dylan , Huang Jonathan Y. , Su Yue , Lim Wee Han , Hudson Fay E. , Escott Christopher C. , Morello Andrea , Yang Chih Hwan , Dzurak Andrew S. , Saraiva Andre , Laucht Arne
Published: February 2023

The small size and excellent integrability of silicon metal–oxide–semiconductor (SiMOS) quantum dot spin qubits make them an attractive system for mass‐manufacturable, scaled‐up quantum processors. Furthermore, classical control electronics can be integrated on‐chip, in‐between the qubits, if an architecture with sparse arrays of qubits is chosen. In such an architecture qubits are either transported across the chip via shuttling or coupled via mediating quantum systems over short‐to‐intermediate distances. This paper investigates the charge and spin characteristics of an elongated quantum dot—a so‐called jellybean quantum dot—for the prospects of acting as a qubit–qubit coupler. Charge transport, charge sensing, and magneto‐spectroscopy measurements are performed on a SiMOS quantum dot device at mK temperature and compared to Hartree–Fock multi‐electron simulations. At low electron occupancies where disorder effects and strong electron–electron interaction dominate over the electrostatic confinement potential, the data reveals the formation of three coupled dots, akin to a tunable, artificial molecule. One dot is formed centrally under the gate and two are formed at the edges. At high electron occupancies, these dots merge into one large dot with well‐defined spin states, verifying that jellybean dots have the potential to be used as qubit couplers in future quantum computing architectures.
User‐Controlled 4D Biomaterial Degradation with Substrate‐Selective Sortase Transpeptidases for Single‐Cell Biology
Authors: Bretherton Ross C. , Haack Amanda J. , Kopyeva Irina , Rahman Fariha , Kern Jonah D. , Bugg Darrian , Theberge Ashleigh B. , Davis Jennifer , DeForest Cole A.
Published: February 2023

Stimuli‐responsive biomaterials show great promise for modeling disease dynamics ex vivo with spatiotemporal control over the cellular microenvironment. However, harvesting cells from such materials for downstream analysis without perturbing their state remains an outstanding challenge in 3/4‐dimensional (3D/4D) culture and tissue engineering. In this manuscript, a fully enzymatic strategy for hydrogel degradation that affords spatiotemporal control over cell release while maintaining cytocompatibility is introduced. Exploiting engineered variants of the sortase transpeptidase evolved to recognize and selectively cleave distinct peptide sequences largely absent from the mammalian proteome, many limitations implicit to state‐of‐the‐art methods to liberate cells from gels are sidestepped. It is demonstrated that evolved sortase exposure has minimal impact on the global transcriptome of primary mammalian cells and that proteolytic cleavage proceeds with high specificity; incorporation of substrate sequences within hydrogel crosslinkers permits rapid and selective cell recovery with high viability. In composite multimaterial hydrogels, it is shown that sequential degradation of hydrogel layers enables highly specific retrieval of single‐cell suspensions for phenotypic analysis. It is expected that the high bioorthogonality and substrate selectivity of the evolved sortases will lead to their broad adoption as an enzymatic material dissociation cue and that their multiplexed use will enable newfound studies in 4D cell culture.
Modulation of Schottky Barrier Height by Nitrogen Doping and Its Influence on Responsivity of Monolayer MoS2 Photodetector
Authors: Polumati Gowtham , Kolli Chandra Sekhar Reddy , Selamneni Venkatarao , Salazar Mario Flores , De Luna Bugallo Andres , Sahatiya Parikshit
Published: February 2023

Monolayer MoS2 flakes are prepared by low‐pressure chemical vapor deposition on p‐type and n‐type silicon substrates and post‐treated under nitrogen (N2)‐rich conditions to incorporate nitrogen atoms in sulfur vacancies. Ultraviolet photoelectron spectroscopy (UPS) shows an increase in work function value by 0.47 eV and 0.53 eV compared to undoped MoS2 when grown on p and n‐type substrates, respectively. Photodetection experiments conducted for doped and undoped MoS2 grown on p‐type substrate reveal a decrease in the value of photo responsivity for N2 doped MoS2 (191 A W−1) compared with undoped MoS2 (572 A W−1). Also, MoS2 crystals grown and doped on an n‐type substrate display an important enhancement of the photoresponsivity from 63 A W−1 for undoped to 606 A W−1 for N2 doped MoS2. The modulation of Schottky barrier height for N2 doped MoS2 on p type substrate decreased whereas for n type substrate the high electric field created due to the difference in the Fermi level allows for greater separation of photogenerated charge carriers. This modulation in the photoresponsivity due to the selection of the type of substrate opens up new avenues of research and engineering of atomically thin optoelectronic devices.
Shallow Traps in Carbon Nitride Quantum Dots to Achieve 6.47 s Ultralong Lifetime and Wavelength‐Tunable Room Temperature Phosphorescence
Authors: Han Bingyan , Lei Xiangshan , Li Dan , Liu Qingdong , Chen Yajun , Wang Jiao , He Gaohong
Published: February 2023

Room temperature phosphorescent (RTP) carbon dots (CDs) have the defects of short lifetime, single wavelength, and poor stability. Most approaches to achieve RTP CDs are based on stabilizing excited triplet state excitons and suppressing nonradiative transitions by providing a rigid environment. The internal structure of CDs has not been followed to address the issue of triplet state exciton quenching. Herein, boron (B) is doped into the framework of carbon nitride quantum dots (CNQDs) to create BN bonds and generate trap state, thus reducing the degree of conjugation and constructing defects. The excited triplet excitons are captured by the defects and stored in the traps from which they escape under thermal activation—this in turn gives rise to an ultralong lifetime RTP. Based on the abovementioned considerations, 6.47 s ultralong‐lifetime deep blue RTP CNQDs with phosphorescent emission wavelength at 418 nm are achieved. This is a significantly longer lifetime than for most deep‐blue RTP CDs. By increasing the conjugation of the precursor, another 1.55 s of green RTP CNQDs at 530 nm is obtained. The difference in lifetime and wavelength between the two phosphorescent CNQDs as well as their excellent stability leads to potential applications in anti‐counterfeiting and information encryption.
Gold Au(I)6 Clusters with Ligand‐Derived Atomic Steric Locking: Multifunctional Optoelectrical Properties and Quantum Coherence
Authors: Chandra Sourov , Sciortino Alice , Das Susobhan , Ahmed Faisal , Jana Arijit , Roy Jayoti , Li Diao , Liljeström Ville , Jiang Hua , Johansson Leena‐Sisko , Chen Xi , Nonappa  , Cannas Marco , Pradeep Thalappil , Peng Bo , Ras Robin H. A. , Sun Zhipei , Ikkala Olli , Messina Fabrizio
Published: February 2023

An atomically precise ultrasmall Au(I)6 nanocluster where the six gold atoms are complexed by three sterically interlocking stabilizing ligands is reported, allowing a unique combination of efficient third harmonic generation (THG), intense photoluminescence quantum yield (35%), ultrafast quantum coherence, and electron accepting properties. The reaction of 6‐(dibutylamino)‐1,3,5‐triazine‐2,4‐dithiol (TRZ) with HAuCl4 leads to complexation by thiolation. However, intriguingly, another reduction step is needed to form the centrosymmetric Au(I)6TRZ3 clusters with the multifunctional properties. Here, ascorbic acid is employed as a mild reducing agent, in contrast to the classic reducing agents, like NaBH4 and NaBH3CN, which often produce mixtures of clusters or gold nanoparticles. Such Au(I)6 nanocluster films produce very strong THG response, never observed for nanoclusters. The clusters also produce brilliant single and multiphoton luminescence with exceptional stability. Density functional theory calculations and femtosecond transient absorption studies suggest ultrafast ligand‐to‐metal charge transfer, quantum coherence with long decoherence time 200–300 fs, and fast propagation of excitation from the core to the surrounding solvent. Finally, novel electron‐accepting ground state properties allow p‐doping of 2D field‐effect transistor devices. Summarizing, the potential of ultrasmall sterically interlocked Au(I) clusters, i.e., complexes allowed by the new sequential reduction protocol, towards multifunctional devices, fast photoswitches, and quantum colloidal devices is shown.
Multipole Analysis of the Extinction Cross Section and Circular Dichroism of Chiral Metamolecules with Optical Theorem
Authors: Zhu Guodong , Sun Zhiguang , Liu Jiayi , Fang Yurui
Published: February 2023

Plasmonic chirality of metamolecules attracts increasing attention because of the tunable circular dichroism (CD) and near‐field enhancement for chiral molecule detection. Although various mechanisms have been proposed to explain the plasmonic CD, the quantitative analysis of particles with sub‐wavelength dimensions remains to be refined. Unlike biomolecules and small particles for which only absorption effects are considered, both multipolar scattering and absorption of sub‐wavelength metamolecules need to be analyzed. Here, the extinction and CD of chiral metamolecules are experimentally measured, and the contribution of excited multipole moments is theoretically investigated via combining multipole scattering and optical theorem. It is found that for the low‐order resonance mode, the absorption dominates the CD signal. While for high‐order resonance modes, both scattering and absorption significantly influence the CD, and the high‐order electric quadrupole moment that is commonly ignored plays a crucial role. Moreover, the intrinsic mechanism of the chiral response is also intuitively explained with linear polarization analysis. The mechanism proposed here is not only applicable for biomolecules and tiny particles with low‐order resonance modes but also works well for sub‐wavelength particles with high‐order modes, where conventional mixed electric and magnetic polarizability mechanisms usually do not work very well.
Bandgap Engineering of Scandium Microspheres for Anti‐Counterfeiting and Multicolor Imaging
Authors: Chen Bin Bin , Wang Yue , Liu Meng Li , Chang Shuai , Lv Jian , Gao Ya Ting , Li Da Wei
Published: February 2023

Bandgap engineering plays an important role in the regulation of the photophysical properties of semiconductor materials. Developing the facile and powerful strategy to achieve bandgap tunability is highly desired. Herein, the bandgap tunability of scandium microspheres prepared by the hydrothermal treatment of Sc3+ ions/l‐glutamine (Sc3+/Gln) complexes is achieved. The continuously decreased bandgap is directly attributed to the increase of carbon element and the decrease of scandium element in scandium microspheres controlled by the Gln ligand, which causes the red‐shifted room temperature phosphorescence from Sc/Gln‐0.15 (3.17 eV, green) to Sc/Gln‐0.25 (2.53 eV, yellow). Meanwhile, scandium microspheres have an excitation‐dependent emission ranged from green to red color, revealing their multi‐color imaging capability. Further increase of Gln ligand can further reduce the bandgap to 1.62 eV (Sc/Gln‐0.3), realizing the transition from photoluminescence to photothermal properties of scandium microspheres. Because of their superior optical properties, scandium microspheres can be well used for advanced anti‐counterfeiting and multicolor imaging. This new finding not only offers a deeper insight into the photophysical structure of rare earth semiconductor materials, but also provides a scalable method for the preparation of scandium microspheres with the desired bandgaps.
Optical Steganography via Programmable Anchoring Boundary of Soft Materials
Authors: Wang Yifei , Liu Binghui , Sun Pei‐Zhi , Hu Hong‐Long , Yuan Cong‐Long , Huang Mengting , Zheng Zhigang
Published: February 2023

Engineering the properties of light with multi‐channel planar elements can produce independent spectral response, and has formed the solid basis for image steganography techniques, which holds great promise for applications including information storage, optical encryption, and anti‐counterfeiting. However, most of the recently reported steganography systems suffer from limited size, sophisticated fabrication, and finite degree of freedom in encoding and decoding process. Herein, a versatile image steganography system based on soft material is proposed. The polarization and intensity of transmitted light are modulated by programing the anchoring boundary of liquid crystals, allowing arbitrary independent images multiplexing in single‐size element with high fidelity. Specifically, the stimuli‐responsiveness of liquid crystals endows the platform with a new degree of freedom to manipulate the transmitted spectrum dynamically, further sketching a prospective framework toward a new type of steganography with fascinating tunability. The proposed strategy sheds new light on multifarious display system by harnessing the stimuli‐responsiveness of soft materials, leading to promising applications in information storing, image steganography, anti‐counterfeiting, and multilevel encryption techniques.
Helically Chiral Donor–Acceptor Double Hetero[4]helicenes with Circularly Polarized Thermally Activated Delayed Fluorescence
Authors: Qu Cheng , Zhu Yunlong , Liang Lu , Ye Kaiqi , Zhang Yuewei , Zhang Hongyu , Zhang Zuolun , Duan Lian , Wang Yue
Published: February 2023

Although helically chiral heterohelicenes are widely adopted in chiroptical studies, those with circularly polarized thermally activated delayed fluorescence (CP‐TADF), which are highly valuable for circularly polarized organic light‐emitting diodes (CP‐OLEDs), are rarely realized. Moreover, the core skeletons of known CP‐TADF heterohelicenes are limited to the p‐ and n‐doped structures with multiresonance effect. In this study, a new type of helically chiral CP‐TADF heterohelicenes featuring a fused donor–acceptor core skeleton is successfully designed and constructed. Enantiomers possessing high configurational stability are achieved and separated, and they efficiently emit CP light with dissymmetry factors reaching 3.1 × 10−3 in doped films. Owing to the excellent photophysical properties, a high‐performance CP‐OLED with the maximum external quantum efficiency of up to 20.0% and an electroluminescence dissymmetry factor reaching 2.9 × 10−3 is obtained. This new type of CP‐TADF heterohelicenes provides a large space for the development of high‐performance CP‐TADF materials for various applications.
Iron‐Catalyzed Positional and Geometrical Isomerization of Alkenes
Authors: Obeid Abdul‐Halim , Hannedouche Jérôme
Published: February 2023

This review outlines the most noteworthy achievements of the last few years in the renascent field of positional and geometrical isomerization of alkenes using iron catalysis, from a mechanistic perspective. Particular attention will be placed on the developments beyond the seminal contributions of iron carbonyl complexes and on their mechanistic aspects underlying the nature of the active iron species. The relevant literature has been covered until late 2022.

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Fractional Dynamics Foster Deep Learning of COPD Stage Prediction
Authors: Yin Chenzhong , Udrescu Mihai , Gupta Gaurav , Cheng Mingxi , Lihu Andrei , Udrescu Lucretia , Bogdan Paul , Mannino David M. , Mihaicuta Stefan
Published: February 2023

Chronic obstructive pulmonary disease (COPD) is one of the leading causes of death worldwide. Current COPD diagnosis (i.e., spirometry) could be unreliable because the test depends on an adequate effort from the tester and testee. Moreover, the early diagnosis of COPD is challenging. The authors address COPD detection by constructing two novel physiological signals datasets (4432 records from 54 patients in the WestRo COPD dataset and 13824 medical records from 534 patients in the WestRo Porti COPD dataset). The authors demonstrate their complex coupled fractal dynamical characteristics and perform a fractional‐order dynamics deep learning analysis to diagnose COPD. The authors found that the fractional‐order dynamical modeling can extract distinguishing signatures from the physiological signals across patients with all COPD stages—from stage 0 (healthy) to stage 4 (very severe). They use the fractional signatures to develop and train a deep neural network that predicts COPD stages based on the input features (such as thorax breathing effort, respiratory rate, or oxygen saturation). The authors show that the fractional dynamic deep learning model (FDDLM) achieves a COPD prediction accuracy of 98.66% and can serve as a robust alternative to spirometry. The FDDLM also has high accuracy when validated on a dataset with different physiological signals.
Mechanobiological Adaptation to Hyperosmolarity Enhances Barrier Function in Human Vascular Microphysiological System
Authors: Kang Joon Ho , Jang Minjeong , Seo Su Jin , Choi Andrew , Shin Daeeun , Seo Suyoung , Lee Soo Hyun , Kim Hong Nam
Published: February 2023

In infectious disease such as sepsis and COVID‐19, blood vessel leakage treatment is critical to prevent fatal progression into multi‐organ failure and ultimately death, but the existing effective therapeutic modalities that improve vascular barrier function are limited. Here, this study reports that osmolarity modulation can significantly improve vascular barrier function, even in an inflammatory condition. 3D human vascular microphysiological systems and automated permeability quantification processes for high‐throughput analysis of vascular barrier function are utilized. Vascular barrier function is enhanced by >7‐folds with 24–48 h hyperosmotic exposure (time window of emergency care; >500 mOsm L−1) but is disrupted after hypo‐osmotic exposure (<200 mOsm L−1). By integrating genetic and protein level analysis, it is shown that hyperosmolarity upregulates vascular endothelial‐cadherin, cortical F‐actin, and cell–cell junction tension, indicating that hyperosmotic adaptation mechanically stabilizes the vascular barrier. Importantly, improved vascular barrier function following hyperosmotic exposure is maintained even after chronic exposure to proinflammatory cytokines and iso‐osmotic recovery via Yes‐associated protein signaling pathways. This study suggests that osmolarity modulation may be a unique therapeutic strategy to proactively prevent infectious disease progression into severe stages via vascular barrier function protection.
Ultrafast Charge Transfer 2D MoS2/Organic Heterojunction for Sensitive Photodetector
Authors: Xu Zhuhua , He Miao , Wu Qinke , Wu Chengcheng , Li Xubiao , Liu Bilu , Tang Man‐Chung , Yao Jie , Wei Guodan
Published: February 2023

The 2D MoS2 with superior optoelectronic properties such as high charge mobility and broadband photoresponse has attracted broad research interests in photodetectors (PD). However, due to the atomic thin layer of 2D MoS2, its pure photodetectors usually suffer from inevitable drawbacks such as large dark current, and intrinsically slow response time. Herein, a new organic material BTP‐4F with high mobility is successfully stacked with 2D MoS2 film to form an integrated 2D MoS2/organic P–N heterojunction, facilitating efficient charge transfer as well as significantly suppressed dark current. As a result, the as‐obtained 2D MoS2/organic (PD) has exhibited excellent response and fast response time of 332/274 µs. The analysis validated photogenerated electron transition from this monolayer MoS2 to subsequent BTP‐4F film, whereas the transited electron is originated from the A− exciton of 2D MoS2 by temperature‐dependent photoluminescent analysis. The ultrafast charge transfer time of ≈0.24 ps measured by time‐resolved transient absorption spectrum is beneficial for efficient electron–hole pair separation, greatly contributing to the obtained fast photoresponse time of 332/274 µs. This work can open a promising window to acquire low‐cost and high‐speed (PD).
Highly Stable Garnet Fe2Mo3O12 Cathode Boosts the Lithium–Air Battery Performance Featuring a Polyhedral Framework and Cationic Vacancy Concentrated Surface
Authors: Qiu Yang , Li Gaoyang , Zhou Huimin , Zhang Guoliang , Guo Liang , Guo Zhanhu , Yang Ruonan , Fan Yuqi , Wang Weiliang , Du Yong , Dang Feng
Published: February 2023

Lithium–air batteries (LABs), owing to their ultrahigh theoretical energy density, are recognized as one of the next‐generation energy storage techniques. However, it remains a tricky problem to find highly active cathode catalyst operating within ambient air. In this contribution, a highly active Fe2Mo3O12 (FeMoO) garnet cathode catalyst for LABs is reported. The experimental and theoretical analysis demonstrate that the highly stable polyhedral framework, composed of FeO octahedrons and MO tetrahedrons, provides a highly effective air catalytic activity and long‐term stability, and meanwhile keeps good structural stability. The FeMoO electrode delivers a cycle life of over 1800 h by applying a simple half‐sealed condition in ambient air. It is found that surface‐rich Fe vacancy can act as an O2 pump to accelerate the catalytic reaction. Furthermore, the FeMoO catalyst exhibits a superior catalytic capability for the decomposition of Li2CO3. H2O in the air can be regarded as the main contribution to the anode corrosion and the deterioration of LAB cells could be attributed to the formation of LiOH·H2O at the end of cycling. The present work provides in‐depth insights to understand the catalytic mechanism in air and constitutes a conceptual breakthrough in catalyst design for efficient cell structure in practical LABs.
Oxygen Vacancies Engineering in Thick Semiconductor Films via Deep Ultraviolet Photoactivation for Selective and Sensitive Gas Sensing
Authors: Abideen Zain Ul , Choi Jun‐Gyu , Yuwono Jodie A. , Kiy Alexander , Kumar Priyank Vijaya , Murugappan Krishnan , Lee Won‐June , Kluth Patrick , Nisbet David R. , Tran‐Phu Thanh , Yoon Myung‐Han , Tricoli Antonio
Published: February 2023

Room‐temperature detection of volatile organic compounds in particle‐per‐billion concentrations is critical for the development of wearable and distributed sensor networks. However, sensitivity and selectivity are limited at low operating temperatures. Here, a strategy is proposed to substantially improve the performance of semiconductor sensors. Tunable oxygen vacancies in thick 3D networks of metal oxide nanoparticles are engineered using deep ultraviolet photoactivation. High selectivity and sensitivity are achieved by optimizing the electronic structure and surface activity while preserving the 3D morphology. Cross‐sectional depth analysis reveals oxygen vacancies present at various depths (≈24% at a depth of 1.13 µm), with a uniform distribution throughout the thick films. This results in ≈58% increase in the sensitivity of ZnO to 20‐ppb ethanol at room temperature while ≈51% and 64% decrease in the response and recovery times, respectively. At an operating temperature of 150 °C, oxygen‐vacant nanostructures achieve a lower limit of detection of 2 ppb. Density functional theory analysis shows that inducing oxygen vacancies reduces activation energy for ethanol adsorption and dissociation, leading to improved sensing performance. This scalable approach has the potential for designing low‐power wearable chemical and bio‐sensors and tuning the activity and band structure of porous, thick oxide films for multiple applications.
Enhancement of Light Extraction Efficiency and Suppression of Roll‐Off Characteristics of Thermally Activated Delayed Fluorescence Organic Light‐Emitting Diodes by Inserting Nanoscale Pixel‐Defining Layer
Authors: Lee Seungwon , Park Jun‐Young , Park Jaewon , Bi Jian Cheng , Kang Byeongwoo , Hwang Young Hyun , Seok Jiwon , Park Young Wook , Ju Byeong‐Kwon
Published: February 2023

Thermally activated delayed fluorescence (TADF) organic molecules are considered the most suitable for blue organic light‐emitting diodes (OLEDs) after extensive research; however, they are plagued by issues of internally guided light and the roll‐off characteristics contributed by triplet exciton‐utilized emission. Thus, this study leverages exciton diffusion guidance and energy extraction to simultaneously achieve optical efficiency enhancement and roll‐off characteristic suppression of mixed‐host blue TADF OLEDs. The array of nanopixels, defined by the inserted nanoscale pixel‐defining layer (nPDL), spatially separates the excitons and polarons, resulting in the exacerbation of triplet quenching by securing exciton diffusion. Furthermore, through the formation of a metal cathode with a corrugated profile, nonradiative energy transfer to the surface plasmon polaritons is capitalized via Bragg diffraction, thereby boosting the emission efficiency. The structure of the nPDL is judiciously determined by finite‐difference time‐domain computational analysis. Consequently, the device with the optimized nPDL demonstrates 88.4%, 118.8%, and 108.8% improvements in external quantum, current, and power efficiencies, respectively, compared to the reference. Moreover, the critical luminance, which quantifies the degree of roll‐off, is improved by 83.7%. This pioneering demonstration of hybridizing the material combination and nanopatterning techniques is expected to provide new insights for designing high‐performance OLEDs.
Understanding of Low‐Porosity Sulfur Electrode for High‐Energy Lithium–Sulfur Batteries
Authors: Fu Yucheng , Singh Rajesh K , Feng Shuo , Liu Jun , Xiao Jie , Bao Jie , Xu Zhijie , Lu Dongping
Published: February 2023

The lithium–sulfur (Li–S) battery is a promising technology for large‐scale energy storage and vehicle electrification due to its high theoretical energy density and low cost. Reducing the sulfur cathode porosity has been identified recently as a viable strategy for improving the cell practical energy density and minimizing pore‐filling electrolytes to extend cell life at lean electrolyte conditions. Direct use of a low‐porosity cathode for Li–S battery results in poor electrode wetting, nonuniform electrode reactions, and thus early cell failure. To understand and mitigate the barriers associated with the use of low‐porosity electrodes, multiscale modeling is performed to predict electrode wetting, electrolyte diffusion, and their impacts on sulfur reactions in Li–S cells by explicitly considering the electrode wettability impacts and electrode morphologies. The study elucidates the critical impact of low tortuosity and large channel pore design for promoting electrode wetting and species diffusion. It is suggested that the secondary particle size should be comparable with the electrode thickness to effectively promote electrolyte wettability and sulfur reactivity. This study provides new insights into the low‐porosity electrode material and designs and is expected to accelerate the development of practical high‐energy Li–S batteries.
Multifunctional Doping Strategy to Develop High‐Performance Ni‐Rich Cathode Material
Authors: Park Nam‐Yung , Cho Gyeil , Kim Su‐Bin , Sun Yang‐Kook
Published: February 2023

A high fraction of reactive Ni4+ ions at the cathode–electrolyte interfaces lead to capacity fading of Ni‐rich cathodes. Therefore, a core–shell (CS) design encapsulating the Ni‐rich region by a Ni‐less shell is an effective approach for improving the cycling stability of the cathodes. However, with increasing average Ni content to increase the capacity, the thickness of the shell should be reduced or the Ni fraction of the shell will be inevitably higher, making it susceptible to interdiffusion, which flattens the concentration gradient during the lithiation process. Herein, the limit of the average Ni composition in the CS‐type cathode is pushed to 94% via Ta doping, which suppresses interdiffusion by segregating the Ta‐rich phases at the particle boundaries. Ta doping allows the maintenance of the highly aligned microstructure and the ordered intermixing structure of Li and transition metal ions, as well as the concentration gradient, over a wide lithiation temperature range. The Ta‐doped CS‐type cathode retains 92.6% of its initial capacity after 1000 cycles and exhibits resistance to damage from fast charging. Multifunctional Ta doping in the CS‐type cathode provides a simple and all‐around solution to maximize the electrochemical performance of Ni‐rich cathodes, providing flexibility in the lithiation process.
Probing the electrostatic aggregation of nanoparticles with oppositely charged molecular ions
Authors: Huang Jianxiang , Buratto Damiano , Zhou Ruhong
Published: February 2023

The co‐assembly of charged nanoparticles with oppositely charged molecular ions has emerged as a promising technique in the fabrication of nanoparticle superstructures. However, the underlying mechanism behind these molecular ions in mediating the repulsion between these charged nanoparticles remains elusive. Herein, coarse‐grained molecular dynamics simulations are used to elucidate the effects of valency, shape, and size of molecular anions on their co‐assembly with gold nanoparticles coated with positively charged ligands. The findings suggest that the valency, shape, and size of molecular anions significantly influence the repulsion and aggregating dynamics among these positively charged nanoparticles. Moreover, the free energy calculations reveal that ring‐shaped molecular anions with higher valences and larger sizes are more effective at reducing the repulsion between these gold nanoparticles and thus enhance the stability of the aggregate. This study contributes to a better understanding of the critical roles of valence, shape, and size of ions in mediating the electrostatic co‐assembly of nanoparticles with oppositely charged ions, and it also guides the future design of DNA templates and DNA origami in co‐assembly with oppositely charged nanoparticles.
Photo‐responsive Single‐Molecule Magnet Showing 0D to 1D Single‐Crystal‐to‐Single‐Crystal Structural Transition and Hysteresis Modulation
Authors: Huang Xin‐Da , Ma Xiu‐Fang , Zheng Li‐Min
Published: February 2023

Photo‐responsive lanthanide‐based single‐molecule magnets (SMM) hold great promise for future switching and memory devices. Herein, we report a dysprosium phosphonate [DyIII(SCN)2(NO3)(depma)2(4‐hpy)2] (1Dy), which features a supramolecular framework containing layers of hydrogen‐bonding network and pillars of π–π interacted anthracene units. The photocycloaddition reaction of anthracene pairs led to a rapid and reversible single‐crystal‐to‐single‐crystal (SC–SC) structural transition to form the 1D coordination polymer [DyIII(SCN)2(NO3)(depma2)(4‐hpy)2]n(2Dy), accompanied by photoswitchable SMM properties with the reduction of effective energy barrier by half and the narrowing of the butterfly‐like hysteresis loop. The diluted sample showed a photo‐induced switch of the blocking temperature (TB) from 3.8 K for1Dy@Yto 2.6 K for2Dy@Y. This work may inspire the construction of lanthanide‐based molecular materials with targeted photo‐responsive magnetic properties.
Impact of mechanochemical treatment on surface chemistry and flocculation of kaolinite dispersion
Authors: Bhatti Qaisar Abbas , Baloch Musa Kaleem , Schwarz Simona , Ishaq Muhammad
Published: February 2023

For many industrial applications, an extensive research of the stabilization and destabilization mechanisms of aqueous suspensions of fine particles is crucial. The flocculation of charged particles from their aqueous suspensions is greatly influenced by the surface characteristics of the particles. For the purpose of improving the flocculation efficiency of kaolin suspensions, the impact of the proposed mechanochemical treatment, which includes homogenization and/or ultrasonication followed by the addition of polycation such as poly (diallyl dimethyl‐ammonium chloride) (PDADMAC), was examined under standard conditions. It was demonstrated that parameters including kaolin's specific surface area, surface charge density, and particle size reduction are all affected by the duration of the ultrasonication. While ultrasonication (10 min) has a significant impact on particle size distributions, 300 and 200 nm‐sized particles were also seen. A narrow flocculation window was obtained by PDADMAC at a Cp/Cs ratio of 0.1 mg/g (Cp/Cs means the ratio of mass polymer/mass substrate), while the mechanical treatment via homogenization with magnetic stirring (60 min) resulted in a larger flocculation window of kaolin caused by the polyelectrolyte used. However, mechanochemical treatment via ultrasonication followed by the addition of aforementioned polyelectrolyte played a significant role in achieving the highest turbidity removal. Hence, the settling behavior of kaolin suspension depends upon the pH, ultra‐sonication time, and the concentration of polyelectrolyte. The combination of ultra‐sonication, PDADMAC dosage, and pH (mechanic‐chemical treatment) played an excellent role in the maximum removal of turbidity, and the broadest flocculation window comprising of 0.4 to 1.6 mg/g was observed at pH 8.
Chiral Self‐Sorting in Pd6L12 Metal‐Organic Cages
Authors: Ghorai Sandipan , Maji Suman , Paul Bhaswati , Samanta Krishanu , Kumar Sen Shovan , Natarajan Ramalingam
Published: February 2023

Chiral self‐sorting during the formation of cage‐like molecules continues to fascinate and advance our understanding of the phenomenon in general. Herein, we report the chiral self‐sorting in the Pd6L12‐type metal‐organic cages. When a racemic mixture of axially chiral bis‐pyridyl ligands undergo coordination‐driven self‐assembly with Pd(II) ions to form Pd6L12‐type cages, the system has the option of chiral self‐sorting to afford any of at least 70 pairs of (one homochiral and 69 heterochiral) enantiomers and 5 meso isomers or a statistical mixture of everything. However, the system resulted in diastereoselective self‐assembly through a high‐fidelity chiral social self‐sorting to form a racemic mixture of D3 symmetric heterochiral [Pd6(L6R/6S)12]12+/[Pd6(L6S/6R)12]12+ cages.
Universally Exhaustive Generation of Molecular Structures and Prediction of Their Electronic States Using Machine Learning for N‐type Organic Transistor Materials
Authors: Ohno Akira , Hanna Jun‐ichi , Iino Hiroaki , Nakago Kosuke , Yamaguchi Taiki , Abe Motoki , Akita Hirotaka , Takemoto Mizuki
Published: February 2023

We have proposed a new method for the exploration of organic functional molecules, using an exhaustive molecular generator combined without combinatorial explosion and electronic state predicted by machine learning and adapted for developing n‐type organic semiconductor molecules for field‐effect transistors. Our method first enumerates skeletal structures as much as possible and next generates fused ring structures using substitution operations for atomic nodes and bond edges. We have succeeded in generating more than 4.8 million molecules. We calculated the electron affinity (EA) of about 51 thousand molecules with DFT calculation and trained the graph neural networks to estimate EA values of generated molecules. Finally, we obtained the 727 thousand molecules as candidates that satisfy EA values over 3 eV. The number of these possible candidate molecules is far beyond what we have been able to propose based on our knowledge and experience in synthetic chemistry, indicating a wide diversity of organic molecules.
Halogen Bond‐Involving Supramolecular Assembly Utilizing Carbon as a Nucleophilic Partner of I⋅⋅⋅C Non‐covalent Interaction
Authors: Smirnov Andrey S. , Mikherdov Alexander S. , Rozhkov Anton V. , Gomila Rosa M. , Frontera Antonio , Kukushkin Vadim Yu. , Bokach Nadezhda A.
Published: February 2023

Co‐crystallization of 180°‐orienting σ‐hole‐accepting tectons, namely, 1,4‐diisocyanobenzene (1) and 1,4‐diisocyanotetramethylbenzene (2), with such homoditopic halogen bond donors as 1,4‐diiodotetrafluorobenzene (1,4‐FIB) and 4,4’‐diiodoperfluorobiphenyl (4,4’‐FIBP) afforded co‐crystals 1 ⋅ 1,4‐FIB, 1 ⋅ 4,4’‐FIBP, and 2 ⋅ 1,4‐FIB. Their solid‐state structures exhibit 1D‐supramolecular arrangements, which are based on poorly explored I⋅⋅⋅C halogen bonding; this study is the first in which the supramolecular assembly utilizing halogen bonding with a terminal C atom was performed. The use of the potentially tetrafunctional σ‐hole accepting tetraiodoethylene (TIE) leads to supramolecular architecture of a higher dimension, 3D‐framework, observed in the structure of 1 ⋅ TIE. DFT calculations, used to characterize the halogen bonding situation, revealed that the I⋅⋅⋅C non‐covalent interactions are moderately strong, ranging from −4.07 in 1 ⋅ TIE to −5.45 kcal/mol in 2 ⋅ 1,4‐FIB. The NBO analysis disclosed that LP(C)→σ* charge transfer effects are relevant in all co‐crystals.
Few‐layer Graphene Lithiophilic and Sodiophilic Diffusion Layer on Porous Stainless Steel as Lithium and Sodium Metal Anodes
Authors: Patrike Apurva , Wasnik Kundan , Shelke Manjusha V.
Published: February 2023

In order to subdue the obvious problem of uneven electric field distribution on regularly used copper/aluminum current collectors for alkali metal batteries, graphene on porous stainless steel (pSS_Gr) was fabricated using the ion etching technique that is employed as an effective host for lithium and sodium metal anodes. The binder‐free pSS_Gr demonstrated stable Li plating and stripping at areal current and capacity of 6 mA cm−2 and 2.54 mAh cm−2, respectively, for over 1000 cycles with 98% coulombic efficiency (C.E.). Also, in the case of Na metal anode, the host has shown stable performance at 4 mA cm−2 and 1 mAh cm−2 over 1000 cycles with ∼100% C.E.. Further, a full cell composed of Li‐plated pSS_Gr as an anode and LiFePO4 as a cathode is electrochemically tested at 50 mA g−1 current density with stable 100 cycles.
Event‐triggered state estimation for nonlinear systems aid by machine learning
Authors: Huong D. C. , Nguyen T. N. , Le H. T. , Trinh H.
Published: February 2023

The event‐triggered state estimation problem with the aid of machine learning for nonlinear systems is considered in this paper. First, we develop a recurrent neural network (RNN) model to predict the nonlinear systems. Second, we design a discrete‐time dynamic event‐triggered mechanism (ETM) and a state observer based on this ETM for the prediction model. This discrete‐time dynamic event‐triggered state observer significantly reduces the utilization of communication resources. Third, we establish a sufficient condition to ensure that the state observer can robustly estimate the state vector of the RNN model. Finally, we provide an illustrative example to verify the merit of the obtained results.
Black holes as “time capsules”: A cosmological graviton background and the Hubble tension
Authors: Piran Tsvi , Jimenez Raul
Published: February 2023

Minuscule primordial black holes (BHs) before the end and after inflation can serve as “time capsules” bringing back energy from the past to a later epoch when they evaporate. As these BHs behave like matter, while the rest of the universe's content behaves like radiation, the mass fraction of these BHs, which is tiny at formation, becomes significant later. If sufficiently small, these BHs will evaporate while the Universe is still radiation dominated. We revisit this process and point out that gravitons produced during evaporation behave as “dark radiation.” If the initial BHs are uniformly distributed so will the gravitons and in this case, they will be free of Silk damping and avoid current limits on “dark radiation” scenarios. Seeds for such BHs can arise during the last phases of inflation. We show here that with suitable parameters, this background graviton field can resolve the Hubble tension. We present current observational constraints on this scenario and suggest upcoming observational tests to prove or refute it. Finally, we also elaborate on the graviton background produced by particle annihilation during the Planck era or shortly after inflation.
Integrated UPLC–Q‐TOF–MS and network pharmacology approach‐driven quality marker discovery of Danggui Shaoyao San for primary dysmenorrhea
Authors: Li Zhe , Xiong Hui , Li Na , Zhao Lanqingqing , Liu Zi , Yu Yongzhou , Zhao Chunying
Published: February 2023

Danggui Shaoyao San (DSS), a famous prescription, has been clinically proved to be effective in treating primary dysmenorrhea (PD). Currently there is no valid quality control data available for DSS. The main aim of the current research was to explore quality markers (Q‐markers) of DSS. The chemical constituents of DSS were qualitatively identified using ultra‐performance liquid chromatography tandem quadrupole time of flight mass spectrometry (UPLC–Q‐TOF–MS) technology. On this basis, the targets of DSS and PD were predicted and screened using the TCMSP, SwissTargetPrediction, GeneCards, OMIM and TTD databases. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis was performed on the core intersection targets using string and Cytoscape 3.7.1 software. Then molecular docking was conducted to screen the Q‐markers of DSS in PD. A total of 126 chemical constituents, including 22 organic acids, 14 phthalides, 24 monoterpenoids, five sesquiterpene lactones, 22 triterpenoids, four phenylpropanoids and 35 other compounds were preliminarily characterized. According to network pharmacology prediction analysis, six compounds containing polyporenic acid C, senkyunolide P, alisol B 23‐acetate, naringenin, gallic acid, ferulic acid and albiflorin were regarded as Q‐markers of DSS. The present research established an integrative UPLC–Q‐TOF–MS and network pharmacology method to discover the latent Q‐markers of DSS and provided a theoretical data for the follow‐up quality control of DSS.
Engineering strategies of metal‐organic frameworks toward advanced batteries
Authors: Sun Ruimin , Dou Mingyue , Chen Ziliang , Wang Ruirui , Zheng Xiangyi , Zhang Yuxiang , Zhou Chenggang , Menezes Prashanth W.
Published: February 2023

Metal‐organic frameworks (MOFs) integrate several advantages such as adjustable pore sizes, large specific surface areas, controllable geometrical morphology, and feasible surface modification. Benefiting from these appealing merits, MOFs have recently been extensively explored in the field of advanced secondary batteries. However, a systematic summarization of the specific functional units that these materials can act as in batteries as well as their related design strategies to underline their functions has not been perceived to date. Motivated by this point, this review dedicates to the elucidation of diverse functions of MOFs for batteries, which involve the electrodes, separators, interface modifiers, and electrolytes. Particularly, the main engineering strategies based on the physical and chemical features to enable their enhanced performance have been highlighted for the individual functions. In addition, perspectives and possible research questions in the future development of these materials have also been outlined. This review captures such progress ranging from fundamental understanding and optimized protocols to multidirectional applications of MOF‐based materials in advanced secondary batteries.
Promoting the application of pediatric radiomics via an integrated medical engineering approach
Authors: Zheng Haige , Wang Fang , Li Yang , Li Zhicheng , Zhang Xiaochun , Yin Xuntao
Published: February 2023

Radiomics is widely used in adult tumors but has been rarely applied to the field of pediatrics. Promoting the application of radiomics in pediatric diseases, especially in the early diagnosis and stratified treatment of tumors, is of great value to the realization of the WHO 2030 “Global Initiative for Childhood Cancer.” This paper discusses the general characteristics of radiomics, the particularity of its application to pediatric diseases, and the current status and prospects of pediatric radiomics. Radiomics is a data‐driven science, and the combination of medicine and engineering plays a decisive role in improving data quality, data diversity, and sample size. Compared with adult radiomics, pediatric radiomics is significantly different in data type, disease spectrum, disease staging, and progression. Some progress has been made in the identification, classification, stratification, survival prediction, and prognosis of tumor diseases. In the future, big data applications from multiple centers and cross‐talent training should be strengthened to improve the benefits for clinical workers and children.
Adjuvant and neo‐adjuvant immunotherapy in resectable non‐small cell lung cancer (NSCLC): Current status and perspectives
Authors: Xu Ziyi , Zou Zihua , Hao Xuezhi , Xing Puyuan , Li Junling
Published: February 2023

Surgery followed by adjuvant chemotherapy is the standard of care for selected patients with early‐stage or locally advanced non‐small cell lung cancer (NSCLC). However, many of these patients still experience postoperative recurrence at 5 years. At present, peri‐operative treatment methods are emerging to prevent early relapse, such as targeted therapy and immunotherapy. Investigation on predictive biomarkers of responses to adjuvant and neoadjuvant therapies is also continuously ongoing. Immunotherapy represented by immune checkpoint inhibitors (ICIs), either by monotherapy or in combination with chemotherapy, has shown benefit in promoting pathological responses and prolonging survival for patients with NSCLC without oncogenic mutations. Exploratory studies have also provided evidence regarding the selection of patients who benefit from ICI‐based perioperative treatment. This review focuses on the existing data of current clinical trials of adjuvant and neoadjuvant strategies with ICIs in resectable NSCLC, the exploration of predictive biomarkers, and the perspectives and urgent challenges in the future.