Arranging ionic liquids (ILs) with long‐range order can not only enhance their performance in a desired application, but can also help elucidate the vital between structure and properties. However, ...this is still a challenge and no example has been reported to date. Herein, we report a feasible strategy to achieve a crystalline IL via coordination self‐assembly based reticular chemistry. IL1MOF, was prepared by designing an IL bridging ligand and then connecting them with metal clusters. IL1MOF has a unique structure, where the IL ligands are arranged on a long‐range ordered framework but have a labile ionic center. This structure enables IL1MOF to break through the typical limitation where the solid ILs have lower proton conductivity than their counterpart bulk ILs. IL1MOF shows 2–4 orders of magnitude higher proton conductivity than its counterpart IL monomer across a wide temperature range. Moreover, by confining the IL within ultramicropores (<1 nm), IL1MOF suppresses the liquid–solid phase transition temperatures to lower than −150 °C, allowing it to function with high conductivity in a subzero temperature range.
A reticular chemistry based strategy opens a facile toolbox for designing liquid molecules with long‐rang‐ordered framework of MOF. IL1MOF is the first crystalline ionic liquid (IL) combining a balance of good mechanical properties and high conductivity. It expands the use of IL electrolytes to an low temperature region.
The unstable feature of the widely employed organic hole‐transporting materials (HTMs) (e.g., spiro‐MeOTAD) significantly limits the practical application of perovskite solar cells (PSCs). Therefore, ...it is desirable to design new structured PSCs with stable HTMs presenting excellent carrier extraction and transfer properties. This work demonstrates a new inverted PSC configuration. The new PSC has a graded band alignment and bilayered inorganic HTMs (i.e., compact NiOx and mesoporous CuGaO2). In comparison with planar‐structured PSCs, the mesoporous CuGaO2 can effectively extract holes from perovskite due to the increased contact area of the perovskite/HTM. The graded energy alignment constructed in the ultrathin compact NiOx, mesoporous CuGaO2, and perovskite can facilitate carrier transfer and depress charge recombination. As a result, the champion device based on the newly designed mesoscopic PSCs yields a stabilized efficiency of ≈20%, which is considered one of the best results for inverted PSCs with inorganic HTMs. Additionally, the unencapsulated PSC device retains more than 80% of its original efficiency when subjected to thermal aging at 85 °C for 1000 h in a nitrogen atmosphere, thus demonstrating superior thermal stability of the device. This study may pave a new avenue to rational design of highly efficient and stable PSCs.
A graded bilayered inorganic hole‐transporting layer (including compact NiOx and mesoporous CuGaO2) is developed for inverted perovskite solar cells. The resulting devices demonstrate both high efficiency, with the champion one giving a stabilized efficiency of ≈20% and superior thermal stability with >80% of the initial efficiency being retained subject to 1000 hours' thermal aging at 85 °C.
We report acute antibody responses to SARS-CoV-2 in 285 patients with COVID-19. Within 19 days after symptom onset, 100% of patients tested positive for antiviral immunoglobulin-G (IgG). ...Seroconversion for IgG and IgM occurred simultaneously or sequentially. Both IgG and IgM titers plateaued within 6 days after seroconversion. Serological testing may be helpful for the diagnosis of suspected patients with negative RT-PCR results and for the identification of asymptomatic infections.
Dysregulated prefrontal control over amygdala is engaged in the pathogenesis of psychiatric diseases including depression and anxiety disorders. Here we show that, in a rodent anxiety model induced ...by chronic restraint stress (CRS), the dysregulation occurs in basolateral amygdala projection neurons receiving mono-directional inputs from dorsomedial prefrontal cortex (dmPFC→BLA PNs) rather than those reciprocally connected with dmPFC (dmPFC↔BLA PNs). Specifically, CRS shifts the dmPFC-driven excitatory-inhibitory balance towards excitation in the former, but not latter population. Such specificity is preferential to connections made by dmPFC, caused by enhanced presynaptic glutamate release, and highly correlated with the increased anxiety-like behavior in stressed mice. Importantly, low-frequency optogenetic stimulation of dmPFC afferents in BLA normalizes the enhanced prefrontal glutamate release onto dmPFC→BLA PNs and lastingly attenuates CRS-induced increase of anxiety-like behavior. Our findings thus reveal a target cell-based dysregulation of mPFC-to-amygdala transmission for stress-induced anxiety.
One‐dimensional (1D) nanostructured oxides are proposed as excellent electron transport materials (ETMs) for perovskite solar cells (PSCs); however, experimental evidence is lacking. A facile ...hydrothermal approach was employed to grow highly oriented anatase TiO2 nanopyramid arrays and demonstrate their application in PSCs. The oriented TiO2 nanopyramid arrays afford sufficient contact area for electron extraction and increase light transmission. Moreover, the nanopyramid array/perovskite system exhibits an oriented electric field that can increase charge separation and accelerate charge transport, thereby suppressing charge recombination. The anatase TiO2 nanopyramid array‐based PSCs deliver a champion power conversion efficiency of approximately 22.5 %, which is the highest power conversion efficiency reported to date for PSCs consisting of 1D ETMs. This work demonstrates that the rational design of 1D ETMs can achieve PSCs that perform as well as typical mesoscopic and planar PSCs.
Nanopyramid arrays of 1D highly oriented anatase TiO2 present an oriented electric field distribution, which is favorable for charge separation and transport. An impressive power conversion efficiency of approximately 22.5 % was achieved, which is the highest efficiency reported for perovskite solar cells consisting of 1D electron transport materials to date.
A copper(I) 3,5‐diphenyltriazolate metal–organic framework (CuTz‐1) was synthesized and extensively characterized by using a multi‐technique approach. The combined results provided solid evidence ...that CuTz‐1 features an unprecedented Cu5tz6 cluster as the secondary building unit (SBU) with channels approximately 8.3 Å in diameter. This metal–organic framework (MOF) material, which is both thermally and chemically (basic and acidic) stable, exhibited semiconductivity and high photocatalytic activity towards the degradation of dyes in the presence of H2O2. Its catalytic performance was superior to that of reported MOFs and comparable to some composites, which has been attributed to its high efficiency in generating .OH, the most active species for the degradation of dyes. It is suggested that the photogenerated holes are trapped by CuI, which yields CuII, the latter of which behaves as a catalyst for a Fenton‐like reaction to produce an excess amount of .OH in addition to that formed through the scavenging of photogenerated electrons by H2O2. Furthermore, it was shown that a dye mixture (methyl orange, methyl blue, methylene blue, and rhodamine B) could be totally decolorized by using CuTz‐1 as a photocatalyst in the presence of H2O2 under the irradiation of a Xe lamp or natural sunlight.
In the frame: A thermally and chemically stable CuI–triazolate metal–organic framework (CuTz‐1) was prepared and demonstrated to exhibit high photocatalytic activity towards the degradation of dyes in the presence of H2O2 (see figure for dye decolorization). CuTz‐1 could be used as a catalyst for at least four cycles without significant change to the crystallinity and catalytic activity.
Gaining information about an unknown gas source is a task of great importance with applications in several areas, including responding to gas leaks or suspicious smells, quantifying sources of ...emissions, or in an emergency response to an industrial accident or act of terrorism. In this paper, a method to estimate the source term of a gaseous release using measurements of concentration obtained from an unmanned aerial vehicle (UAV) is described. The source term parameters estimated include the three‐dimensional location of the release, its emission rate and other important variables needed to forecast the spread of the gas using an atmospheric transport and dispersion model. The parameters of the source are estimated by fusing concentration observations from a gas detector on‐board the aircraft, with meteorological data and an appropriate model of dispersion. Two models are compared in this paper, both derived from analytical solutions to the advection–diffusion equation. Bayes’ theorem, implemented using a sequential Monte Carlo algorithm, is used to estimate the source parameters to take into account the large uncertainties in the observations and formulated models. The system is verified with novel, outdoor, fully automated experiments, where observations from the UAV are used to estimate the parameters of a diffusive source. The estimation performance of the algorithm is assessed subject to various flight path configurations and wind speeds. Observations and lessons learned during these unique experiments are discussed, and areas for future research are identified.
In this paper we present new methods for solving multi-criteria decision-making problem in an intuitionistic fuzzy environment. First, we define an evaluation function for the decision-making problem ...to measure the degrees to which alternatives satisfy and do not satisfy the decision-maker’s requirement. Then, we introduce and discuss the concept of intuitionistic fuzzy point operators. By using the intuitionistic fuzzy point operators, we can reduce the degree of uncertainty of the elements in a universe corresponding to an intuitionistic fuzzy set. Furthermore, a series of new score functions are defined for multi-criteria decision-making problem based on the intuitionistic fuzzy point operators and the evaluation function and their effectiveness and advantage are illustrated by examples.
Antimony is an attractive anode material for sodium‐ion batteries (SIBs) owing to its high theoretical capacity and appropriate sodiation potential. However, its practical application is severely ...impeded by its poor cycling stability caused by dramatic volumetric variations during sodium uptake and release processes. Here, to circumvent this obstacle, Sb@C@TiO2 triple‐shell nanoboxes (TSNBs) are synthesized through a template‐engaged galvanic replacement approach. The TSNB structure consists of an inner Sb hollow nanobox protected by a conductive carbon middle shell and a TiO2‐nanosheet‐constructed outer shell. This structure offers dual protection to the inner Sb and enough room to accommodate volume expansion, thus promoting the structural integrity of the electrode and the formation of a stable solid–electrolyte interface film. Benefiting from the rational structural design and synergistic effects of Sb, carbon, and TiO2, the Sb@C@TiO2 electrode exhibits superior rate performance (212 mAh g−1 at 10 A g−1) and outstanding long‐term cycling stability (193 mAh g−1 at 1 A g−1 after 4000 cycles). Moreover, a full cell assembled with a configuration of Sb@C@TiO2//Na3(VOPO4)2F displays a high output voltage of 2.8 V and a high energy density of 179 Wh kg−1, revealing the great promise of Sb@C@TiO2 TSNBs as the electrode in SIBs.
Sb@C@TiO2 triple‐shell nanoboxes (TSNBs) composed of an inner Sb hollow nanobox protected by a conductive carbon middle shell and a TiO2‐nanosheet‐constructed outer shell are synthesized through a template‐engaged galvanic replacement approach. Benefiting from the rational structural design,the Sb@C@TiO2 TSNBs exhibit enhanced sodium storage performance in terms of superior rate performance and outstanding long‐term cycling stability.
Catalytic kinetic resolution (KR) and dynamic kinetic asymmetric transformation (DyKAT) are alternative and complementary avenues to access chiral stereoisomers of both starting materials and ...reaction products. The development of highly efficient chiral catalytic systems for kinetically controlled processes has therefore been one of the linchpins in asymmetric synthesis. N‐heterocyclic carbene (NHC)/copper cooperative catalysis has enabled highly efficient KR and DyKAT of racemic N‐tosylaziridines by 3+3 annulation with isatin‐derived enals, leading to highly enantioenriched N‐tosylaziridine derivatives (up to >99 % ee) and a large library of spirooxindole derivatives with high structural diversity and stereoselectivity (up to >95:5 d.r., >99 % ee). Mechanistic studies suggest that the NHC can bind reversibly to the copper catalyst without compromising its catalytic activity and regulate the catalytic activity of the copper complex to switch the chemoselection between KR and DyKAT.
Highly efficient kinetic resolution and dynamic kinetic asymmetric transformation of racemic N‐tosylaziridines with isatin‐derived enals have been achieved by the cooperative catalysis of chiral N‐heterocyclic carbene (NHC) and copper complexes, leading to highly enantioenriched N‐tosylaziridines and spirooxindole derivatives with high structural diversity.
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