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Lead‐free metal halide double perovskites have emerged as promising scintillators owing to their superior optoelectronic properties, low‐cost and solution processability. However, it is still challenging to develop high‐performance flexible X‐ray scintillators based on the B(I)‐site alkali metal modulation in lead‐free double perovskite nanocrystals (NCs). Herein, a series of novel Cs2B(I)GdCl6 (B: Li, Na, K) of double perovskite A2B(I)M(III)X6 NCs structures are successfully synthesized, the optical and scintillator properties of which are significantly sensitive to the B(I)‐site alkali metals with the doping of Sb3+. They showed efficient self‐trapped exciton (STE) emission with high photoluminescence quantum yield (PLQY) and exhibited the highest X‐ray detection limit (86 nGyair s−1) and excellent spatial resolutions (>15 lp mm−1). The femtosecond transient absorption measurement and theoretical analysis further revealed that the B(I)‐site alkali metal fundamentally balanced the exciton–phonon coupling with appropriate STEs formation energy barrier and the electron localization and thus improved the optical and scintillator properties. This B(I)‐site alkali metal engineering offers a strategy to develop bright luminescent double perovskite NCs for X‐ray detection and imaging devices. [ABSTRACT FROM AUTHOR]

Mitochondria are key signaling hubs for innate immune responses. In this issue, Wu et al (2022) report that remodeling of the outer mitochondrial membrane by the linear ubiquiting chain assembly complex (LUBAC) facilitates transport of activated NF‐κB to the nucleus in response to TNF signaling. [ABSTRACT FROM AUTHOR]

Lead‐free halide perovskites have triggered interest in the field of optoelectronics and photocatalysis because of their low toxicity, and tunable optical and charge‐carrier properties. From an application point of view, it is desirable to develop stable multifunctional lead‐free halide perovskites. We have developed a series of Cs2PtxSn1−xCl6 perovskites (0≤x≤1) with high stability, which show switchable photoluminescence and photocatalytic functions by varying the amount of Pt4+ substitution. A Cs2PtxSn1−xCl6 solid solution with a dominant proportion of Pt4+ shows broadband photoluminescence with a lifetime on the microsecond timescale. A Cs2PtxSn1−xCl6 solid solution with a small amount of Pt4+ substitution exhibits photocatalytic hydrogen evolution activity. An optical spectroscopy study reveals that the switch between photoluminescence and photocatalysis functions is controlled by sub‐band gap states. Our finding provides a new way to develop lead‐free multifunctional halide perovskites with high stability. [ABSTRACT FROM AUTHOR]

Lead‐free halide perovskites have triggered interest in the field of optoelectronics and photocatalysis because of their low toxicity, and tunable optical and charge‐carrier properties. From an application point of view, it is desirable to develop stable multifunctional lead‐free halide perovskites. We have developed a series of Cs2PtxSn1−xCl6 perovskites (0≤x≤1) with high stability, which show switchable photoluminescence and photocatalytic functions by varying the amount of Pt4+ substitution. A Cs2PtxSn1−xCl6 solid solution with a dominant proportion of Pt4+ shows broadband photoluminescence with a lifetime on the microsecond timescale. A Cs2PtxSn1−xCl6 solid solution with a small amount of Pt4+ substitution exhibits photocatalytic hydrogen evolution activity. An optical spectroscopy study reveals that the switch between photoluminescence and photocatalysis functions is controlled by sub‐band gap states. Our finding provides a new way to develop lead‐free multifunctional halide perovskites with high stability. [ABSTRACT FROM AUTHOR]

Ultrabright fluorescent nanoparticles (NPs) hold great promise for demanding bioimaging applications. Recently, extremely bright molecular crystals of cationic fluorophores were obtained by hierarchical coassembly with cyanostar anion‐receptor complexes. These small‐molecule ionic isolation lattices (SMILES) ensure spatial and electronic isolation to prohibit aggregation quenching of dyes. We report a simple, one‐step supramolecular approach to formulate SMILES materials into NPs. Rhodamine‐based SMILES NPs stabilized by glycol amphiphiles show high fluorescence quantum yield (30 %) and brightness per volume (5000 M−1 cm−1/nm3) with 400 dye molecules packed into 16‐nm particles, corresponding to a particle absorption coefficient of 4×107 M−1 cm−1. UV excitation of the cyanostar component leads to higher brightness (>6000 M−1 cm−1/ nm3) by energy transfer to rhodamine emitters. Coated NPs stain cells and are thus promising for bioimaging. [ABSTRACT FROM AUTHOR]

Ultrabright fluorescent nanoparticles (NPs) hold great promise for demanding bioimaging applications. Recently, extremely bright molecular crystals of cationic fluorophores were obtained by hierarchical coassembly with cyanostar anion‐receptor complexes. These small‐molecule ionic isolation lattices (SMILES) ensure spatial and electronic isolation to prohibit aggregation quenching of dyes. We report a simple, one‐step supramolecular approach to formulate SMILES materials into NPs. Rhodamine‐based SMILES NPs stabilized by glycol amphiphiles show high fluorescence quantum yield (30 %) and brightness per volume (5000 M−1 cm−1/nm3) with 400 dye molecules packed into 16‐nm particles, corresponding to a particle absorption coefficient of 4×107 M−1 cm−1. UV excitation of the cyanostar component leads to higher brightness (>6000 M−1 cm−1/ nm3) by energy transfer to rhodamine emitters. Coated NPs stain cells and are thus promising for bioimaging. [ABSTRACT FROM AUTHOR]

Cells must adjust their redox state to an ever-changing environment that could otherwise result in compromised homeostasis. An obvious way to adapt to changing redox conditions depends on cysteine post-translational modifications (PTMs) to adapt conformation, localization, interactions and catalytic activation of proteins. Such PTMs should occur preferentially in the proximity of oxidative stress sources. A particular concentration of these sources is found near membranes where the endoplasmic reticulum (ER) and the mitochondria interact on domains called MERCs (Mitochondria-Endoplasmic Reticulum Contacts). Here, fine inter-organelle communication controls metabolic homeostasis. MERCs achieve this goal through fluxes of Ca2+ ions and inter-organellar lipid exchange. Reactive oxygen species (ROS) that cause PTMs of mitochondria-associated membrane (MAM) proteins determine these intertwined MERC functions. Chronic changes of the pattern of these PTMs not only control physiological processes such as the circadian clock but could also lead to or worsen many human disorders such as cancer and neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

Transition metal cobalt (oxy)hydroxides are promising catalyst candidates for the oxygen evolution reaction (OER). Their activity can be significantly enhanced by doping chromium; however, the optimal catalyst elemental composition is unknown, and the exact role of Cr remains elusive. Here, density functional theory (DFT) calculations and comprehensive catalyst characterization are combined to address these two questions. Guided by DFT calculations, a series of amorphous ternary Co‐iron(Fe)‐Cr (oxy)hydroxides with systematically tuned elemental compositions are synthesized. Performance atlases of these catalysts are established based on different experimental descriptors, which show that the optimal Co5Fe3Cr2 (oxy)hydroxide reaches a current density of 10 mA cm−2 at an overpotential of 232 mV. It delivers a Co‐based mass activity of 1486 A g−1 and a high turnover frequency of 0.23 s−1, over two orders higher than monometallic Co (oxy)hydroxide. X‐ray absorption and photoelectron spectroscopies reveal that Cr promotes Co atoms to occupy octahedral sites and modifies the Co electronic structure. Quasi‐operando electron energy loss spectroscopy further experimentally confirm that Cr accelerates the pre‐oxidation of Co2+ to higher valence species, resulting in significantly higher catalytic activity. The findings here pave the way to use Co–Fe–Cr (oxy)hydroxides as an efficient OER catalyst. [ABSTRACT FROM AUTHOR]

Cells must adjust their redox state to an ever-changing environment that could otherwise result in compromised homeostasis. An obvious way to adapt to changing redox conditions depends on cysteine post-translational modifications (PTMs) to adapt conformation, localization, interactions and catalytic activation of proteins. Such PTMs should occur preferentially in the proximity of oxidative stress sources. A particular concentration of these sources is found near membranes where the endoplasmic reticulum (ER) and the mitochondria interact on domains called MERCs (Mitochondria-Endoplasmic Reticulum Contacts). Here, fine inter-organelle communication controls metabolic homeostasis. MERCs achieve this goal through fluxes of Ca2+ ions and inter-organellar lipid exchange. Reactive oxygen species (ROS) that cause PTMs of mitochondria-associated membrane (MAM) proteins determine these intertwined MERC functions. Chronic changes of the pattern of these PTMs not only control physiological processes such as the circadian clock but could also lead to or worsen many human disorders such as cancer and neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

Octahedral coordinated trivalent cobalt cations (CoOh3+) in metal oxyhydroxides are highly active catalytic sites for the oxygen evolution reaction (OER), a critical bottleneck for efficient water splitting; however, previous synthetic methods have limited control over these sites. Herein, a scalable electrodeposition method coupled with in situ oxidation to produce amorphous Co–Fe–W trimetallic oxyhydroxides enriched with CoOh3+ is developed. X‐ray absorption, in operando spectroscopic analysis, and computational studies reveal that 72% of the Co atoms are present in CoOh3+ sites. Fe and W synergistically affect the electronic structure of Co and provide a favorable coordination environment. The Co–Fe–W oxyhydroxide exhibits superior OER catalytic performance with an impressive turnover frequency of 1.96 s−1 at an overpotential of 300 mV, a low Tafel slope of 32 mV dec−1, and small activation energy of 53 kJ mol−1 in alkaline electrolyte. The catalyst directly deposited on Ni foams can serve as a robust OER electrode in two‐electrode water electrolyzers; they deliver a current density of 100 mA cm−2 at a small overpotential of 234 mV in alkaline electrolyte with excellent durability under 100 mA cm−2 over 120 h. These catalysts are excellent for practical water splitting applications. [ABSTRACT FROM AUTHOR]

This paper proposes an approach for detecting anomalies in a wind turbine (WT) based on multivariate analysis. Firstly, the stacked denoising autoencoders (SDAE) model with moving window and multiple noise levels is developed to reconstruct the normal operating data. The correlations among multivariable and temporal dependency inherent in each variable can be captured simultaneously with moving window processing. Both the coarse-grained and fine-grained features of input data can be learned by training with multiple noise levels. Then, the monitoring indicator is derived from the reconstruction error. The threshold value of monitoring indicator is determined by statistical analysis of the values of the monitoring indicator during normal operation. To identify the most relevant parameter related to the detected anomaly in WT, the contribution degree to which each parameter contributes to the exceedance of the threshold is calculated. Finally, the abnormal level is quantified according to the overlap between test behavior distribution and baseline condition to provide supports for operation and maintenance planning of WT. Demonstration on real SCADA data collected from a wind farm in Eastern China shows that the proposed method is effective for the anomaly detection and early warning of an actual WT. • A novel approach for detecting anomaly in wind turbine is presented. • Moving window processing is adopted to incorporate the temporal dependence. • Multiple noise levels training is proposed to improve the detection performance. • The abnormal level of a wind turbine is quantitatively assessed. [ABSTRACT FROM AUTHOR]

The sensing mechanism of a fluoride‐anion probe BODIPY‐amidothiourea (1c) has been elucidated through the density functional theory (DFT) and time‐dependent density functional theory (TDDFT) calculations. The theoretical study indicates that in the DMSO/water mixtures the fluorescent sensing has been regulated by the fluoride complex that formed between the probe 1c/two water molecules and the fluoride anion, and the excited‐state intermolecular hydrogen bond (H‐B) plays an important role in the fluoride sensing mechanism. In the first excited state, the H‐Bs of the fluoride complex 1cFH2 are overall strengthened, which induces the weak fluorescence emission. In addition, molecular orbital analysis demonstrates that 1cFH2 has more obvious intramolecular charge transfer (ICT) character in the S1 state than 1cH2 formed between the probe 1c and two water molecules, which also gives reason to the weaker fluorescence intensity of 1cFH2. Further, our calculated UV‐vis absorbance and fluorescence spectra are in accordance with the experimental measurements. © 2018 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Abstract: Lead‐free perovskite nanocrystals (NCs) were obtained mainly by substituting a Pb2+ cation with a divalent cation or substituting three Pb2+ cations with two trivalent cations. The substitution of two Pb2+ cations with one monovalent Ag+ and one trivalent Bi3+ cations was used to synthesize Cs2AgBiX6 (X=Cl, Br, I) double perovskite NCs. Using femtosecond transient absorption spectroscopy, the charge carrier relaxation mechanism was elucidated in the double perovskite NCs. The Cs2AgBiBr6 NCs exhibit ultrafast hot‐carrier cooling (<1 ps), which competes with the carrier trapping processes (mainly originate from the surface defects). Notably, the photoluminescence can be increased by 100 times with surfactant (oleic acid) added to passivate the defects in Cs2AgBiCl6 NCs. These results suggest that the double perovskite NCs could be potential materials for optoelectronic applications by better controlling the surface defects. [ABSTRACT FROM AUTHOR]

Abstract: Lead‐free perovskite nanocrystals (NCs) were obtained mainly by substituting a Pb2+ cation with a divalent cation or substituting three Pb2+ cations with two trivalent cations. The substitution of two Pb2+ cations with one monovalent Ag+ and one trivalent Bi3+ cations was used to synthesize Cs2AgBiX6 (X=Cl, Br, I) double perovskite NCs. Using femtosecond transient absorption spectroscopy, the charge carrier relaxation mechanism was elucidated in the double perovskite NCs. The Cs2AgBiBr6 NCs exhibit ultrafast hot‐carrier cooling (<1 ps), which competes with the carrier trapping processes (mainly originate from the surface defects). Notably, the photoluminescence can be increased by 100 times with surfactant (oleic acid) added to passivate the defects in Cs2AgBiCl6 NCs. These results suggest that the double perovskite NCs could be potential materials for optoelectronic applications by better controlling the surface defects. [ABSTRACT FROM AUTHOR]

Lead-based perovskite nanocrystals (NCs) have outstanding optical properties and cheap synthesis conferring them a tremendous potential in the field of optoelectronic devices. However, two critical problems are still unresolved and hindering their commercial applications: one is the fact of being lead-based and the other is the poor stability. Lead-free all-inorganic perovskite Cs3Bi2X9 (X=Cl, Br, I) NCs are synthesized with emission wavelength ranging from 400 to 560 nm synthesized by a facile room temperature reaction. The ligand-free Cs3Bi2Br9 NCs exhibit blue emission with photoluminescence quantum efficiency (PLQE) about 0.2 %. The PLQE can be increased to 4.5 % when extra surfactant (oleic acid) is added during the synthesis processes. This improvement stems from passivation of the fast trapping process (2-20 ps). Notably, the trap states can also be passivated under humid conditions, and the NCs exhibited high stability towards air exposure exceeding 30 days. [ABSTRACT FROM AUTHOR]

Lead-based perovskite nanocrystals (NCs) have outstanding optical properties and cheap synthesis conferring them a tremendous potential in the field of optoelectronic devices. However, two critical problems are still unresolved and hindering their commercial applications: one is the fact of being lead-based and the other is the poor stability. Lead-free all-inorganic perovskite Cs3Bi2X9 (X=Cl, Br, I) NCs are synthesized with emission wavelength ranging from 400 to 560 nm synthesized by a facile room temperature reaction. The ligand-free Cs3Bi2Br9 NCs exhibit blue emission with photoluminescence quantum efficiency (PLQE) about 0.2 %. The PLQE can be increased to 4.5 % when extra surfactant (oleic acid) is added during the synthesis processes. This improvement stems from passivation of the fast trapping process (2-20 ps). Notably, the trap states can also be passivated under humid conditions, and the NCs exhibited high stability towards air exposure exceeding 30 days. [ABSTRACT FROM AUTHOR]

In this article, the sensing mechanism of cyanide anion chemosensor 2-((2-phenyl-2H-1,2,3-triazol-4-yl)methylene)malononitrile ( M1 ) has been investigated through the density functional theory (DFT) and time-dependent density functional theory (TDDFT) methods. The theoretical results demonstrate that the reaction barrier of 13.02 kcal/mol means a favorable response speed of the chemosensor M1 for cyanide anion. Cyanide anion attacks C=C double bond and hinders the ICT process from the malononitrile moiety to the fluorophore phenyl ring. The high viscosity of DMSO restrains the twisting of the group, inhibits the formation of the ICT state in the first excited state. Due to weak ICT character, the nucleophilic addition product shows the dramatic “off–on” fluorescence enhancement. Meanwhile, intramolecular charge transfer (ICT) mechanism accounts for how different solvents influence the fluorescence spectra. That is, more obvious ICT character of product in EtOH causes fluorescence quenching. The “reaction-based” recognition mode and large bond energy between M1 and cyanide anion minimize the interference by other anions, such as F − , AcO − . Thus, the chemosensor M1 has a high selectivity for cyanide. [ABSTRACT FROM AUTHOR]

[Display omitted] • The CoRu/NC-700 electrocatalyst was synthesized with ZIF-67 as precursor. • CoRu/NC-700 exhibits excellent HER performance and stability in the wide range of pH. • Pyridinic N synergistically enhanced the HER activity of CoRu alloy nanoparticals. The construction of efficient pH-universal hydrogen evolution reaction (HER) electrocatalysts remain enormous challenges for hydrogen production from water electrolysis. Herein, we reported a HER electrocatalyst composed of cobalt-ruthenium alloy nanoparticles with the synergy of pyridinic N (CoRu/NC-700). CoRu/NC-700 exhibits excellent HER performance and stability in acidic, alkaline and neutral media, and can reach 10 mA cm−2 with overpotential of only 6, 10 and 30 mV, respectively. Especially in alkaline and acidic media, overpotential of only 217 and 227 mV are required to achieve 1000 mA cm−2, respectively, which is of great significance for industrialized hydrogen produced by electrolysis of water. KSCN and H 3 PO 4 poisoning experiments prove that such high HER activity is attributed to the synergistic enhancement effect of pyridinic N on CoRu nanoparticles. This work will lay the foundation for the designing and development of novel and efficient pH-universal HER electrocatalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel ruthenium single atom electrocatalyst coordinated with Cl and N (Ru–Cl–N SAC) was synthesized. • The Ru–Cl–N SAC exhibited outstanding electrocatalytic performance for HER, OER and ORR. • The introduction of Cl atom account for the improved trifunctional catalytic activity of Ru–Cl–N SAC. • A overall water splitting cell and a rechargeable Zn-air battery was fabricated using Ru–Cl–N SAC. Design and fabrication of multifunctional efficient and durable single-atom electrocatalyst is highly desirable and challenging for overall water splitting and zinc-air battery. Herein, a novel and efficient ruthenium coordinated with Cl and N single atom catalyst (Ru–Cl–N SAC) is synthesized. Electrochemical measurements disclose that the Ru–Cl–N SAC exhibits superior electrocatalytic activities toward hydrogen evolution reaction (HER), oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) with long-term durability in alkaline medium. Furthermore, the overall water splitting cell requiring only 1.49 V to achieve a current density of 10 mA cm−2 and a rechargeable zinc-air battery with a specific capacity of 804.26 mAh g−1 and long-term durability for 360 h are fabricated based on the Ru–Cl–N SAC. The present work will pave the way for design and fabrication of novel and efficient multifunctional electrocatalysts in the realm of energy conversion and storage. [ABSTRACT FROM AUTHOR]

So far, coumarin dyes have been extensively studied with various means to understand their photophysical behaviors and properties. Here, our performing time-dependent density functional theory calculation is aimed at exploring the excited-state hydrogen bonding dynamics of coumarin 153 (C153) in protic ethanol (EtOH) solvent. The calculated results suggest that the excited-state hydrogen bond CO⋯HO between CO group and OH group in the C153-EtOH complex is strengthened, and the S0 → S1 transition of the complex corresponds to the highest occupied molecular orbital (HOMO) hopping to the lowest unoccupied molecular orbital (LUMO). The excited-state hydrogen bond strengthening has been further confirmed by its larger binding energy in the S1 state than in the S0 state. In addition, because of the formation of the hydrogen bond CO⋯HO, a red shift of about 7 nm occurs in the electronic spectra of the C153-EtOH complex, which is in good accordance with the experiment result. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Glycopeptides such as vancomycin and telavancin are essential for treating infections caused by Gram-positive bacteria. But the dwindling availability of new antibiotics and the emergence of resistant bacteria are making effective antibiotic treatment increasingly difficult. Ramoplanin, an inhibitor of bacterial cell wall biosynthesis, is a highly effective antibiotic against a wide range of Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus, vancomycin-intermediate resistant Clostridium difficile and vancomycin-resistant Enterococcus sp. Here, two tailoring enzyme genes in the biosynthesis of ramoplanin were deleted by double in-frame gene knockouts to produce new ramoplanin derivatives. The deschlororamoplanin A2 aglycone was purified and its structure was identified with LC-MS/MS. Deschlororamoplanin A2 aglycone and ramoplanin aglycone showed similar activity to ramoplanin A2. The results showed that α-1,2-dimannosyl disaccharide at Hpg11 and chlorination at Chp17 in the ramoplanin structure are not essential for its antimicrobial activity. This work provides new precursor compounds for the semisynthetic modification of ramoplanin. [ABSTRACT FROM AUTHOR]

Sulfoxide is an ideal functional group containing S=O for exploring excited-state hydrogen bond dynamics. Benzene-pyrene-sulfoxide (BPS) molecule, as one of the important fluorescent chemosensors, was selected to complete the hydrogen bond dynamics of sulfoxides functional group connecting to methanol (MeOH). The ground-state and excited-state geometric structures were investigated based on density functional theory and the time-dependent density functional theory methods, respectively. The calculated absorption and emission spectra of BPS chemosensor agreed well with the experimental results, demonstrating the theory we adopted is reasonable and effective. The phenomenon of variable-length S=O and H-O bands in the first excited state (S) as well as variable-short hydrogen bond S=O···H-O demonstrated that the intermolecular hydrogen bond were strengthened. Bathochromic shift stretching vibrational modes of both S=O and H-O regions in the S state manifested hydrogen bond were strengthened authentically. In addition, the frontier molecular orbitals (MOs), depicting the nature of the electronically excited states, supported that the S state of BPS-MeOH was a local excited state with a π-π* transition, whereas the second excited state was the charge transfer state. [ABSTRACT FROM AUTHOR]

Abstract: Gentamicin is an aminoglycoside antibiotic obtained from cultures of Micromonospora as the important anti-infective agents. Gentamicin which lacks 3′-hydroxyl group can avoid the attack from the modification enzymes of antibiotic-resistant bacteria in clinic. Consequently, C-3′ dehydroxylation is the key step in gentamicins biosynthesis. We suppose that there are some enzymes responsible for converting intermediate JI-20A to 3′,4′-bisdehydroxylated final product gentamicin C1a, while phosphorylation of 3′-OH is possibly the first step for C-3′ dehydroxylation. The gentamicin biosynthetic gene gntI, encoding an aminoglycoside phosphotransferase, was cloned from Micromonospora echinospora ATCC15835 and overexpressed in Escherichia coli. The resulting phosphotransferase was purified, and the kinetic parameters for Kanamycin A, Kanamycin B, Neomycin B and Amikacin were determined. Elucidation of NMR data of phosphorylated kanamycin B has unambiguously demonstrated a regiospecific phosphorylation of 3′-hydroxyl of the 6-aminohexose ring. The results described here partly confirm that the 3′-dehydroxylation step is preceded by a 3′ phosphorylation step. It is predicted that GntI belongs to a new aminoglycoside phosphotransferase group involved with aminoglycoside antibiotics biosynthesis pathway. [Copyright &y& Elsevier]

Triplet exciton‐based long‐lived phosphorescence is severely limited by the thermal quenching at high temperature. Herein, we propose a novel strategy based on the energy transfer from triplet self‐trapped excitons to Mn2+ dopants in solution‐processed perovskite CsCdCl3. It is found the Mn2+ doped hexagonal phase CsCdCl3 could simultaneously exhibit high emission efficiency (81.5 %) and long afterglow duration time (150 s). Besides, the afterglow emission exhibits anti‐thermal quenching from 300 to 400 K. In‐depth charge‐carrier dynamics studies and density functional theory (DFT) calculation provide unambiguous evidence that carrier detrapping from trap states (mainly induced by Cl vacancy) to localized emission centers ([MnCl6]4−) is responsible for the afterglow emission with anti‐thermal quenching. Enlightened by the present results, we demonstrate the application of the developed materials for optical storage and logic operation applications. [ABSTRACT FROM AUTHOR]

Triplet exciton‐based long‐lived phosphorescence is severely limited by the thermal quenching at high temperature. Herein, we propose a novel strategy based on the energy transfer from triplet self‐trapped excitons to Mn2+ dopants in solution‐processed perovskite CsCdCl3. It is found the Mn2+ doped hexagonal phase CsCdCl3 could simultaneously exhibit high emission efficiency (81.5 %) and long afterglow duration time (150 s). Besides, the afterglow emission exhibits anti‐thermal quenching from 300 to 400 K. In‐depth charge‐carrier dynamics studies and density functional theory (DFT) calculation provide unambiguous evidence that carrier detrapping from trap states (mainly induced by Cl vacancy) to localized emission centers ([MnCl6]4−) is responsible for the afterglow emission with anti‐thermal quenching. Enlightened by the present results, we demonstrate the application of the developed materials for optical storage and logic operation applications. [ABSTRACT FROM AUTHOR]

Strong carrier‐phonon coupling‐induced self‐trapped excitons (STEs) limit the application of 2D double‐perovskites in optoelectronic devices because the separation and collection of the highly localized STEs are challenging. In this study, antimony (Sb) is incorporated into (BA)4AgBiBr8 (BA = CH3(CH2)3NH3+) to form (BA)4AgSbxBi1‐xBr8 (0 ≤ x ≤ 1) trivalent‐metal alloyed 2D double‐perovskites. It is found that introducing Sb into the (BA)4AgBiBr8 2D double‐perovskite will decrease the carrier‐phonon coupling strength and change STEs from "dark" states to "bright" states at room temperature. Combining detailed spectroscopic analysis with density functional theory calculation, it is concluded that STEs localized at [SbBr6] octahedron in (BA)4AgSbxBi1‐xBr8 give the broadband bright emission. The "bright" STEs with moderate carrier‐phonon coupling opens the possibility to efficiently separate and collect charge‐carriers in (BA)4AgSbBr8 2D double‐perovskites. Photodetectors based on (BA)4AgSbBr8 crystals are further fabricated. The photodetectors exhibit high responsivity up to 1368 A W−1 and an external quantum efficiency of 4.7 × 105. These figures are over three times higher than that in (BA)4AgBiBr8‐based photodetectors. This study provides a unique strategy for developing high‐performance optoelectronic devices based on STEs. [ABSTRACT FROM AUTHOR]

The stereodynamics for H+HD and its isotopic variant D+HD were studied with a quasi-classical trajectory (QCT) method at a collision energy of 0.7 eV on the ground 1A′ potential energy surface (PES). The polarization-dependent differential cross-sections (PDDCSs) in the center-of-mass frame are presented here. Furthermore, the distribution of the angle between k and j′, p( θ) and the distribution of the dihedral angle p( ϕ) were calculated and are discussed. The results indicate that isotopic substitution exerts substantial effects on the differential cross-section and the product's rotational polarization. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease for which there is currently no cure. Progress in the characterization of other neurodegenerative mechanisms has shifted the spotlight onto an intracellular structure called mitochondria-endoplasmic reticulum (ER) contacts (MERCs) whose ER portion can be biochemically isolated as mitochondria-associated membranes (MAMs). Within the central nervous system (CNS), these structures control the metabolic output of mitochondria and keep sources of oxidative stress in check via autophagy. The most relevant MERC controllers in the ALS pathogenesis are vesicle-associated membrane protein-associated protein B (VAPB), a mitochondria-ER tether, and the ubiquitin-specific chaperone valosin containing protein (VCP). These two systems cooperate to maintain mitochondrial energy output and prevent oxidative stress. In ALS, mutant VAPB and VCP take a central position in the pathology through MERC dysfunction that ultimately alters or compromises mitochondrial bioenergetics. Intriguingly, both proteins are targets themselves of other ALS mutant proteins, including C9orf72, FUS, or TDP-43. Thus, a new picture emerges, where different triggers cause MERC dysfunction in ALS, subsequently leading to well-known pathological changes including endoplasmic reticulum (ER) stress, inflammation, and motor neuron death. [ABSTRACT FROM AUTHOR]

[Display omitted] • CrCr PBA as a novel anode material for aqueous Na ion batteries. • Cr at both P and R sites in CrCr PBA participate Na ion intercalation/extraction, achieving a high specific capacity. • The low redox potentials of CrCr PBA boost the voltage of aqueous Na ion batteries. • Combining with a MnFe PBA cathode, the full aqueous Na ion battery displays excellent performances. Aqueous sodium-ion batteries (A-SIBs) are a cost-effective and safe battery candidate for stationary energy storage systems. Prussian blue and its analogues (PBAs) have been studied as cathode materials in A-SIBs. However, few studies have used PBAs as anode materials because of their small specific capacity and low cell voltages. Herein, we report that chromium hexacycnochromate (CrCr PBA) can serve as an efficient anode material to enable high-performance A-SIBs. CrCr PBA contains Cr ions at two types of sites coordinated by C and N, offering two redox pairs at −0.62/−0.65 V and −0.73/−0.77 V (vs. Ag/AgCl electrode), respectively. X-ray photoelectron and electron energy loss spectroscopic characterizations of CrCr PBA at different charge/discharge stages show that Cr at both types of coordinated sites can efficiently participate in Na+ storage, delivering a high specific capacity of 108.2 mAh g−1 at a discharge rate of 0.5 A g−1. Besides, low redox potentials of CrCr PBA also contribute to a higher battery voltage. Coupled with a manganese hexacyanoferrate cathode in a water-in-salt electrolyte (17 M NaClO 4), full coin cells exhibit a high energy density of 81.6 Wh kg−1 and a high capacity of 52.8 mAh g−1 at an average voltage of 1.55 V. They also display a long-cycle-life with 93.01% capacity retention over 500 cycles at 30C with around 100% Coulombic efficiency. Their performance is one of the best among recently reported A-SIBs. Because of their similar energy storage mechanisms, CrCr PBA may also serve as promising anode materials in other types of aqueous alkaline metal-ion batteries (e.g. , lithium-ion battery and potassium-ion battery). [ABSTRACT FROM AUTHOR]

Cell imaging, cyanostar macrocycles, fluorescent dyes, fluorescent nanoparticles, SMILES Keywords: cell imaging; cyanostar macrocycles; fluorescent dyes; fluorescent nanoparticles; SMILES EN cell imaging cyanostar macrocycles fluorescent dyes fluorescent nanoparticles SMILES 1 1 1 04/15/21 20210419 NES 210419 B Zellbildgebung b Ultrahelle Nanopartikel für die Zellbildgebung wurden von Amar H. Flood, Bo W. Laursen et al. im Forschungsartikel auf S. 9536 durch Nanopräzipitation eines Rhodaminfarbstoffs mit einem makrocyclischen Anionenrezeptor hergestellt. Frontispiz: Ultrabright Fluorescent Organic Nanoparticles Based on Small-Molecule Ionic Isolation Lattices. [Extracted from the article]

Cell imaging, cyanostar macrocycles, fluorescent dyes, fluorescent nanoparticles, SMILES Keywords: cell imaging; cyanostar macrocycles; fluorescent dyes; fluorescent nanoparticles; SMILES EN cell imaging cyanostar macrocycles fluorescent dyes fluorescent nanoparticles SMILES 1 1 1 04/15/21 20210419 NES 210419 B Cell Imaging b Ultrabright nanoparticles for live cell imaging were prepared by Amar H. Flood, Bo W. Laursen et al. in their Research Article on page 9450 by nanoprecipitation of fluorescent rhodamine dye with a macrocyclic anion receptor. Frontispiece: Ultrabright Fluorescent Organic Nanoparticles Based on Small-Molecule Ionic Isolation Lattices. [Extracted from the article]

All‐inorganic metal halides with afterglow emission have attracted increasing attention due to their significantly longer afterglow duration and higher stability compared to their organic–inorganic hybrid counterparts. However, their afterglow colors have not yet reached the blue spectral region. Here, we report all‐inorganic copper‐doped Rb2AgBr3 single crystals with ultralong blue afterglow (>300 s) by modulating defect states through doping engineering. The introduction of copper(I) ions into Rb2AgBr3 facilitates the formation of bromine vacancies, thus increasing the density of trap states available for charge storage and enabling bright, persistent emission after ceasing the excitation. Moreover, cascade energy transfer between distinct emissive centers in the crystals results in ultra‐broadband photoluminescence, not only covering the whole white light with near‐unity quantum yield but also extending into the near‐infrared region. This 'cocktail' of exotic light‐emission properties, in conjunction with the excellent stability of copper‐doped Rb2AgBr3 crystals, allowed us to demonstrate their implementation to solid‐state lighting, night vision, and intelligent anti‐counterfeiting. [ABSTRACT FROM AUTHOR]

All‐inorganic metal halides with afterglow emission have attracted increasing attention due to their significantly longer afterglow duration and higher stability compared to their organic–inorganic hybrid counterparts. However, their afterglow colors have not yet reached the blue spectral region. Here, we report all‐inorganic copper‐doped Rb2AgBr3 single crystals with ultralong blue afterglow (>300 s) by modulating defect states through doping engineering. The introduction of copper(I) ions into Rb2AgBr3 facilitates the formation of bromine vacancies, thus increasing the density of trap states available for charge storage and enabling bright, persistent emission after ceasing the excitation. Moreover, cascade energy transfer between distinct emissive centers in the crystals results in ultra‐broadband photoluminescence, not only covering the whole white light with near‐unity quantum yield but also extending into the near‐infrared region. This 'cocktail' of exotic light‐emission properties, in conjunction with the excellent stability of copper‐doped Rb2AgBr3 crystals, allowed us to demonstrate their implementation to solid‐state lighting, night vision, and intelligent anti‐counterfeiting. [ABSTRACT FROM AUTHOR]

Vacancy‐ordered perovskite nanocrystals (NCs) have recently attracted much interest owing to their unique structure and optical properties; however, regulating self‐trapped excitons (STEs) in vacancy‐ordered perovskite NCs to exhibit tunable multicolor emission is still challenging because of the highly localized charge distribution and strong carrier‐phonon coupling. Herein, the first colloidal synthesis of lead‐free vacancy‐ordered Cs2HfCl6 perovskite NCs by a hot‐injection method using hafnium acetylacetonate as metal precursors is reported. The passivation strategy of sub‐bandgap trap states inside Cs2HfCl6 NCs is proposed by doping Sb3+. X‐ray photoelectron spectroscopy (XPS) measurements verify that the passivation of sub‐bandgap trap states may be attributed to the enhanced chemical interaction between the Hf4+ cations and Cl– anions. Simultaneously, the introduction of Sb3+ ions yields a bright orange emission. Employing lanthanide acetylacetonate compounds, four lanthanide ions including Pr3+, Eu3+, Tb3+, and Ho3+ are doped into the Cs2HfCl6 NCs, which achieves tunable multicolor emissions (from blue to green to pink) through the energy transfer from STEs to lanthanide ions. This investigation not only develops a novel vacancy‐ordered perovskite NCs, but also provides effective strategies for tuning the optical properties of lead‐free vacancy‐ordered perovskite NCs. [ABSTRACT FROM AUTHOR]

Multiple facile synthetic strategies for all inorganic perovskite CsPbBr 3 nanocrystals (NCs) have been established and developed, profiting from their excellent performance and great potential applied in the field of photonic and optoelectronic. Here, CsPbBr 3 NCs were synthesized by both hot injection method (method 1) and conversion method (method 2), and the discrepancy of their photophysical properties is elucidated via the complementary studies between time-resolved photoluminescence (TRPL) and transient-absorption (TA) spectroscopy. We found that CsPbBr 3 NCs prepared by conversion method exhibited lower PL quantum yield (QY), which was ascribed to the larger partition of the NCs being passivated from the quenchers from the deep trap states. On the other hand, we also observed different radiative recombination rates between two samples which should be due to various trapping/detrapping times prior to the radiative recombination of the charge carriers in two samples. These results provide better guidance for the development and improvement of synthesis methodology for perovskite NCs. • Both hot injection method and conversion method were applied to prepare CsPbBr 3 NCs. • Time-resolved photoluminescence and transient absorption dynamics of two CsPbBr 3 samples were compared and analyzed. • Photophysical processes of CsPbBr 3 NCs were proposed and discussed. [ABSTRACT FROM AUTHOR]

Reasonable determination of the cyclic resistance of low-plasticity fine-grained tailings is important for the engineering design of new tailings dams. In this paper, a series of monotonic and cyclic triaxial undrained tests were conducted to investigate the mechanical response of low-plasticity fine-grained tailings (Taiping tailings). A unified Viscous Energy Dissipation Ratio (VEDR) was then used to develop an energy-based method to study the failure mode under cyclic loading. The VEDR is a normalized energy ratio based on the relationship between cyclic stress and strain. Collapse failure was observed when the dynamic properties suddenly changed beyond the peak point of VEDR (VEDR peak). These changes included a sudden decrease in VEDR, an abrupt increase in cyclic amplitude strain (ε cyc), and the prominent failure pattern of hysteresis curve. In this regard, VEDR failure criterion was proposed by considering VEDR peak as the failure point. Comparisons based on the effective stress path and the cyclic resistance ratio (CRR) indicate that the VEDR failure criterion is more suitable for determining the CRR than conventional strain-based failure criteria for Taiping tailings. Furthermore, a relationship between the VEDR failure criterion and strain-based failure criterion was introduced. In general, the VEDR failure criterion will provide an insight into the determination of CRR for low-plasticity fine-grained tailings. • An energy method was introduced to study the failure mode of Taiping tailings. • Sudden changes of dynamic properties were observed. • A new energy-based failure criterion was established. • Corresponding strain under the new failure criterion was presented. [ABSTRACT FROM AUTHOR]

CsPbI3 quantum dots (QDs) hold tremendous promise for quantum emitters, but they undergo a considerable energy loss when excited above their optical bandgap, which impedes the utilization of high‐energy photons. Different surface modification strategies have been proposed to improve the phase stability of CsPbI3 QDs, however, little progress has been made to realize high photoluminescence quantum yield (PLQY) with high‐energy photon excitation. Here, a non‐resonant barrier excitation (NRBE) mechanism in conjugated aromatic tetraphenylporphyrin (H2TPP)‐modified CsPbI3 QDs is presented, which enables a high PLQY in the high‐energy excitation regime as well as enhanced phase stability. Particularly, the proposed H2TPP ligand possesses adequate energy depth needed to realize NRBE in CsPbI3 QDs, which allows efficient charge injection from organic ligands to the inorganic core. As a result, the H2TPP‐modified CsPbI3 QDs exhibit enhanced light absorption, large Stokes shift, and near‐unity red emission when excited above the optical bandgap. The findings provide new insights into the ligand design strategies for improving optoelectronic properties. [ABSTRACT FROM AUTHOR]

Most of current metal halide materials, including all inorganic and organic–inorganic hybrids, are crystalline materials with poor workability and plasticity that limit their application scope. Here, we develop a novel class of materials termed polymeric metal halides (PMHs) through introducing polycations into antimony‐based metal halide materials as A‐site cations. A series of PMHs with orange‐yellow broadband emission and large Stokes shift originating from inorganic self‐trapped excitons are successfully prepared, which meanwhile exhibit the excellent processability and formability of polymers. The versatility of these PMHs is manifested as the broad choices of polycations, the ready extension to manganese‐ and copper‐based halides, and the tolerance to molar ratios between polycations and metal halides in the formation of PMHs. The merger of polymer chemistry and inorganic chemistry thus provides a novel generic platform for the development of metal halide functional materials. [ABSTRACT FROM AUTHOR]

Most of current metal halide materials, including all inorganic and organic–inorganic hybrids, are crystalline materials with poor workability and plasticity that limit their application scope. Here, we develop a novel class of materials termed polymeric metal halides (PMHs) through introducing polycations into antimony‐based metal halide materials as A‐site cations. A series of PMHs with orange‐yellow broadband emission and large Stokes shift originating from inorganic self‐trapped excitons are successfully prepared, which meanwhile exhibit the excellent processability and formability of polymers. The versatility of these PMHs is manifested as the broad choices of polycations, the ready extension to manganese‐ and copper‐based halides, and the tolerance to molar ratios between polycations and metal halides in the formation of PMHs. The merger of polymer chemistry and inorganic chemistry thus provides a novel generic platform for the development of metal halide functional materials. [ABSTRACT FROM AUTHOR]

For display applications, it is highly desirable to obtain tunable red/green/blue emission. However, lead‐free perovskite nanocrystals (NCs) generally exhibit broadband emission with poor color purity. Herein, we developed a unique phase transition strategy to engineer the emission color of lead‐free cesium manganese bromides NCs and we can achieve a tunable red/green/blue emission with high color purity in these NCs. Such phase transition can be triggered by isopropanol: from one dimensional (1D) CsMnBr3 NCs (red‐color emission) to zero dimensional (0D) Cs3MnBr5 NCs (green‐color emission). Furthermore, in a humid environment both 1D CsMnBr3 NCs and 0D Cs3MnBr5 NCs can be transformed into 0D Cs2MnBr4⋅2 H2O NCs (blue‐color emission). Cs2MnBr4⋅2 H2O NCs could inversely transform into the mixture of CsMnBr3 and Cs3MnBr5 phase during the thermal annealing dehydration step. Our work highlights the tunable optical properties in single component NCs via phase engineering and provides a new avenue for future endeavors in light‐emitting devices. [ABSTRACT FROM AUTHOR]

For display applications, it is highly desirable to obtain tunable red/green/blue emission. However, lead‐free perovskite nanocrystals (NCs) generally exhibit broadband emission with poor color purity. Herein, we developed a unique phase transition strategy to engineer the emission color of lead‐free cesium manganese bromides NCs and we can achieve a tunable red/green/blue emission with high color purity in these NCs. Such phase transition can be triggered by isopropanol: from one dimensional (1D) CsMnBr3 NCs (red‐color emission) to zero dimensional (0D) Cs3MnBr5 NCs (green‐color emission). Furthermore, in a humid environment both 1D CsMnBr3 NCs and 0D Cs3MnBr5 NCs can be transformed into 0D Cs2MnBr4⋅2 H2O NCs (blue‐color emission). Cs2MnBr4⋅2 H2O NCs could inversely transform into the mixture of CsMnBr3 and Cs3MnBr5 phase during the thermal annealing dehydration step. Our work highlights the tunable optical properties in single component NCs via phase engineering and provides a new avenue for future endeavors in light‐emitting devices. [ABSTRACT FROM AUTHOR]

Background: Cholangiocarcinoma (CCA) refers to a collection of malignancies that are associated with a dismal prognosis. Currently, surgical resection is the only way to cure patients with CCA. Available systemic therapy is limited to gemcitabine plus cisplatin; however, this treatment is palliative in nature. Therefore, there is still a need to explore new effective therapeutic targets to intervene against CCA. Methods: We analyzed the expression of EZH2 and the prognosis of patients in CCA. The proliferation, migration and invasion of CCA cells after gene knockdown and overexpression were examined and validated by a xenograft model and a primary CCA mouse model with corresponding gene intervention. Targeting DNA methylation, and RNA‐sequencing‐based transcriptomic analysis in EZH2 and SUZ12 knockout CCA cells was performed. Bisulfite sequencing polymerase chain reaction (PCR), chromatin immunoprecipitation‐quantitative PCR (ChIP‐qPCR) and reverse‐ChIP assays were performed for research purposes. Results: Increased expression of EZH2 in CCA exhibited a significantly poorer prognosis. DNA hypomethylation of the promoter and increased mRNA levels of secreted frizzled‐related protein 1 (SFRP1) were observed in CCA cells following the inhibition of polycomb repressor complex 2 (PRC2), which was achieved through a knockout of EZH2, SUZ12 and EED, respectively, or treatment with GSK126 and GSK343. Targeting the SFRP1 promoter DNA hypermethylation with dCas9‐DNMT3a decreased the mRNA level of SFRP1. The expression of SFRP1 is regulated by both H3K27me3 and DNA methylation and H3K27me3 plays a crucial role in promoting SFRP1 promotor DNA methylation. GSK343 is a small molecule inhibitor that targets the catalytic activity of EZH2. It effectively inhibits the progression and development of subcutaneous xenografts and primary CCA mouse models. Conclusion: Overall, our data strongly suggested that targeting PRC2 promotes the expression of SFRP1, thereby inhibiting the progression of CCA. Key Points/Headlights: Cholangiocarcinoma (CCA) exhibits elevated expression of EZH2, SUZ12 and EED, resulting in increased levels of H3K27me3.Targeting polycomb repressor complex 2 (PRC2) leads to the removal of H3K27me3 from the secreted frizzled‐related protein 1 (SFRP1) promoter and DNA hypomethylation, thereby activating the transcription of SFRP1.Inhibiting PRC2, including the use of EZH2 inhibitors, holds promise as a potential strategy for developing anti‐cancer drugs for CCA. [ABSTRACT FROM AUTHOR]

High-molybdenum-vanadium high-speed steel is a new type of high-hardenability tool steel with excellent wear resistance, castability, and high-temperature red hardness. This paper proposes a composition design of high-molybdenum-vanadium high-speed steel for rolls, and its specific chemical composition is as follows (wt.%): C2%, Mo7.0%, V7.0%, Si0.3%, Mn0.3%, Ni0.4%, Cr3.0%, and the rest of the iron. This design is characterized by the increase in molybdenum and vanadium in high-speed steel to replace traditional high-speed steel rolls with the tungsten element in order to reduce the heavy elements' tungsten-specific gravity segregation caused by centrifugal casting so that the roll performance is uniform and the stability of use is improved. JMatPro (version 7.0) simulation software is used for the composition design of high-molybdenum-vanadium high-speed steel. The phase composition diagram is analyzed under different temperatures. The content of different phases of the organization in different temperatures is also studied. The martensitic transformation temperature and different tempering temperatures with the different types of compounds and grain sizes are calculated. The process parameters of heat treatment of high-molybdenum-vanadium high-speed steel are optimized. The selection of carbon content and the temperature of M50 are calculated and optimized, and the results show that the range of pouring temperatures, quenching temperatures, annealing temperatures, and tempering temperatures are 1360~1410 °C, 1190~1200 °C, 818~838 °C, and 550~600 °C, respectively. Scanning electron microscope (SEM) analysis of the samples obtained by using the above heat treatment parameters is consistent with the simulation results, which indicates that the simulation has important reference significance for guiding the actual production. [ABSTRACT FROM AUTHOR]

Background: Cholangiocarcinoma (CCA) refers to a collection of malignant tumors that develop from the biliary epithelium. Extensive clinical evidence and epidemiological observations indicate a concerning increase in both the incidence and mortality rates of CCA. Surgical resection is currently the sole available cure for CCA. However, it is unfortunate that only a fraction of patients has access to surgery at the time of diagnosis. Moreover, there is a high incidence of cancer recurrence after resection, and systemic treatments have limited efficacy. Therefore, the identification of novel biomarkers for CCA-targeted molecular therapy remains a crucial task in oncology research. Results: Our study demonstrated that low expression of RSPO3 was associated with poorer survival rates in patients with CCA. We found that the RSPO3 promoter DNA was hypermethylated in CCA, which was correlated with the low expression of RSPO3. The expression of RSPO3 was influenced by the balance between the DNA methyltransferase DNMT3a and the DNA demethylase TET1 in CCA. In vitro and in vivo experiments showed that targeting RSPO3 promoter DNA methylation using dCas9DNMT3a promoted tumorigenicity of CCA, while targeted RSPO3 promoter DNA demethylation using dCas9TET1CD inhibited CCA tumorigenicity. Additionally, in our primary CCA model, knockdown of Rspo3 promoted CCA progression, whereas overexpression of Rspo3 inhibited CCA progression. Conclusions: Our findings suggest that increased methylation and decreased expression of RSPO3 may indicate a poor prognosis in CCA. Restoring RSPO3 expression by targeting promoter DNA demethylation could offer insights for precise treatment of CCA. [ABSTRACT FROM AUTHOR]

Low dimensional lead‐free metal halides have become the spotlight of the research on developing multifunctional optoelectronic materials as their properties show a wide range of tunability. However, most reported low dimensional metal halides only function in the ultra‐violet to visible range due to their large bandgap. Moreover, the organic cation based low dimensional metal halides show limited thermal stability; on the other hand, their inorganic cation based counterparts suffer from limited solution processability. A hybrid cation approach is proposed, where a zero dimensional (0D) metal halide ((DFPD)2CsBiI6) is developed by using mixed organic–inorganic cations: 4, 4‐difluoropiperidine (DFPD) and cesium (Cs+). This ensures both thermal stability and solution processability. Furthermore, [BiI6]3− octahedra are serving as active light absorption units, which ensures the bandgap to be located at the visible region. Its photoluminescence (PL) is further shifted to the near infrared (NIR) region by doping (DFPD)2CsBiI6 with antimony (Sb3+). The developed materials show multifunctional properties: thermochromic behavior, light detection, and NIR light emitting. This study expands the scope of developing multifunctional 0D metal halides. [ABSTRACT FROM AUTHOR]

Single‐component metal halides with white light emission are highly attractive for solid‐state lighting applications, but it is still challenging to develop all‐inorganic lead‐free metal halides with high white‐light emission efficiency. Herein, by rationally introducing silver (Ag) into zero‐dimensional (0D) Cs3Cu2Br5 as new structural building unit, a one‐dimensional (1D) bimetallic halide Cs6Cu3AgBr10 is designed that emits strong warm‐white light with an impressive photoluminescence quantum yield (PLQY) of 94.5% and excellent stability. This structural transformation lowers the conduction band minimum while maintaining the localized nature of the valence band maximum, which is crucial in expanding the excitation spectrum and obtaining efficient self‐trapped excitons (STEs) emission simultaneously. Detailed spectroscopy studies reveal that the white‐light originates from triplet STEs emission, which can be remarkably improved by weakening the strong electron‐phonon coupling and thus suppressing phonon‐induced non‐radiative processes. Moreover, the interesting temperature‐dependent emission behavior, together with self‐absorption‐free property, make Cs6Cu3AgBr10 as sensitive luminescent thermometer and high‐performance X‐ray scintillator, respectively. These findings demonstrate a general approach to achieving effective single‐component white‐light emitters based on lead‐free, all‐inorganic metal halides, thereby opening up a new avenue to explore their versatile applications such as lighting, temperature detection and X‐ray imaging. [ABSTRACT FROM AUTHOR]

Thermally activated delayed fluorescence (TADF) is generally observed in solid‐state organic molecules or metal‐organic complexes. However, TADF in all‐inorganic colloidal nanocrystals (NCs) is rare. Herein, we report the first colloidal synthesis of an air‐stable all‐inorganic lead‐free Cs2ZrCl6 perovskite NCs. The Cs2ZrCl6 NCs exhibit long‐lived triplet excited state (138.2 μs), and feature high photoluminescence (PL) quantum efficiency (QY=60.37 %) due to TADF mechanism. The emission color can be easily tuned from blue to green by synthesizing the mixed‐halide Cs2ZrBrxCl6−x (0≤x≤1.5) NCs. Femtosecond transient absorption and temperature dependent PL measurements are performed to clarify the emission mechanism. In addition, Bi3+ ions are successfully doped into Cs2ZrCl6 NCs, which further extends the PL properties. This work not only develops a new lead‐free halide perovskite NCs for potential optoelectronic applications, but also offers unique strategies for developing new inorganic phosphors. [ABSTRACT FROM AUTHOR]

Thermally activated delayed fluorescence (TADF) is generally observed in solid‐state organic molecules or metal‐organic complexes. However, TADF in all‐inorganic colloidal nanocrystals (NCs) is rare. Herein, we report the first colloidal synthesis of an air‐stable all‐inorganic lead‐free Cs2ZrCl6 perovskite NCs. The Cs2ZrCl6 NCs exhibit long‐lived triplet excited state (138.2 μs), and feature high photoluminescence (PL) quantum efficiency (QY=60.37 %) due to TADF mechanism. The emission color can be easily tuned from blue to green by synthesizing the mixed‐halide Cs2ZrBrxCl6−x (0≤x≤1.5) NCs. Femtosecond transient absorption and temperature dependent PL measurements are performed to clarify the emission mechanism. In addition, Bi3+ ions are successfully doped into Cs2ZrCl6 NCs, which further extends the PL properties. This work not only develops a new lead‐free halide perovskite NCs for potential optoelectronic applications, but also offers unique strategies for developing new inorganic phosphors. [ABSTRACT FROM AUTHOR]

DNA‐stabilized silver nanoclusters (DNA‐AgNCs) are easily tunable emitters with intriguing photophysical properties. Here, a DNA‐AgNC with dual emission in the red and near‐infrared (NIR) regions is presented. Mass spectrometry data showed that two DNA strands stabilize 18 silver atoms with a nanocluster charge of 12+. Besides determining the composition and charge of DNA2[Ag18]12+, steady‐state and time‐resolved methods were applied to characterize the picosecond red fluorescence and the relatively intense microsecond‐lived NIR luminescence. During this process, the luminescence‐to‐fluorescence ratio was found to be excitation‐intensity‐dependent. This peculiar feature is very rare for molecular emitters and allows the use of DNA2[Ag18]12+ as a nanoscale excitation intensity probe. For this purpose, calibration curves were constructed using three different approaches based either on steady‐state or time‐resolved emission measurements. The results showed that processes like thermally activated delayed fluorescence (TADF) or photon upconversion through triplet‐triplet annihilation (TTA) could be excluded for DNA2[Ag18]12+. We, therefore, speculate that the ratiometric excitation intensity response could be the result of optically activated delayed fluorescence. [ABSTRACT FROM AUTHOR]

DNA‐stabilized silver nanoclusters (DNA‐AgNCs) are easily tunable emitters with intriguing photophysical properties. Here, a DNA‐AgNC with dual emission in the red and near‐infrared (NIR) regions is presented. Mass spectrometry data showed that two DNA strands stabilize 18 silver atoms with a nanocluster charge of 12+. Besides determining the composition and charge of DNA2[Ag18]12+, steady‐state and time‐resolved methods were applied to characterize the picosecond red fluorescence and the relatively intense microsecond‐lived NIR luminescence. During this process, the luminescence‐to‐fluorescence ratio was found to be excitation‐intensity‐dependent. This peculiar feature is very rare for molecular emitters and allows the use of DNA2[Ag18]12+ as a nanoscale excitation intensity probe. For this purpose, calibration curves were constructed using three different approaches based either on steady‐state or time‐resolved emission measurements. The results showed that processes like thermally activated delayed fluorescence (TADF) or photon upconversion through triplet‐triplet annihilation (TTA) could be excluded for DNA2[Ag18]12+. We, therefore, speculate that the ratiometric excitation intensity response could be the result of optically activated delayed fluorescence. [ABSTRACT FROM AUTHOR]