bluuebunny/crossref_metadata_2025_split 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

Abstract2D 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

AbstractThe 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

AbstractStimuli‐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

AbstractMonolayer 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

AbstractRoom 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

AbstractAn 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

AbstractPlasmonic 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

AbstractBandgap 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

AbstractEngineering 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

AbstractAlthough 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

AbstractThis 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.magnified image
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

AbstractChronic 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

AbstractIn 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

AbstractThe 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

AbstractLithium–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.