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The TAA passivation mechanism improves the alignment of energy levels between TiO2and perovskite, facilitating electron transport and reducing carrier recombination.

Description: In this review, we have highlighted recent developments in one-dimensional electron transport materials for perovskite solar cells. The potential strategies to further boost device performance are also discussed.

Anxiety is a normal and transitory emotional state that allows the organisms to cope well with the real or perceived threats, while excessive or prolonged anxiety is a key characteristic of anxiety disorders. We have recently revealed that prolonged anxiety induced by chronic stress is associated with the circuit-varying dysfunction of basolateral amygdala projection neurons (BLA PNs). However, it is not yet known whether similar mechanisms also emerge for acute stress-induced, short-lasting increase of anxiety. Here, using a mouse model of acute restraint stress (ARS), we found that ARS mice showed increased anxiety-like behavior at 2 h but not 24 h after stress, and this effect was accompanied by a transient increase of the activity of BLA PNs. Specifically, ex vivo patch-clamp recordings revealed that the increased BLA neuronal activity did not differ among the distinct BLA neuronal populations, regardless of their projection targets being the dorsomedial prefrontal cortex (dmPFC) or elsewhere. We further demonstrated that such effects were mainly mediated by the enhanced presynaptic glutamate release in dmPFC-to-BLA synapses but not lateral amygdala-to-BLA ones. Furthermore, while optogenetically weakening the presynaptic glutamate release in dmPFC-to-BLA synapses ameliorated ARS-induced anxiety-like behavior, strengthening the release increased in unstressed mice. Together, these findings suggest that acute stress causes short-lasting increase in anxiety-like behavior by facilitating synaptic transmission from the prefrontal cortex to the amygdala in a circuit-independent fashion.

Introduction:We developed a convergent trigonometric functions technique (arcCOS, arcSIN) capable of dealing with the virtual source position delivered by different carbon ion energies from the pattern of scanning-passive scatter beam in this study.

A three-dimensional (3D) metal–organic framework (MOF) of [Et2NH2]2[Cd5(BTB)4(DEF)2]·4.75DEF (1; H3BTB = benzene-1,3,5-tribenzoic acid and DEF = N,N′-diethylformamide) sustained by symmetrical Z-shaped Cd5secondary building units (SBUs) with an intrinsically metastable host framework has been prepared and characterized. Upon gentle vacuum (800 Pa) at 50 °C, some encapsulated DEF solvates are released, leading to pore-shape changes and Cd2+coordination geometry distortion. This is followed by DEF solvate migration to only one end of the SBU with concomitant symmetry breaking. Additional time under vacuum promoted further structural distortion and topology changes as authenticated by single-crystal X-ray diffraction studies. This work was initially inspired by unusual gas adsorption isotherms and points to the potentially complicated, nonspectator role of coordinative solvents such as DEF during MOF activation.

Defects at the surface and grain boundaries of the perovskite films are extremely detrimental to both the efficiency and stability of perovskite solar cells (PSCs). Herein, a simple and stable quaternary ammonium halide, named chlormequat chloride (i.e., chlorinated choline chloride, CCC), is introduced to regulate the upper surface chemical environment of perovskite films. The anion (Cl−) and cation [ClCH2CH2N(CH3)3]+in CCC could effectively self-search and passivate positively and negatively charged ionic defects in perovskites, respectively, which contributes to inhibited nonradiative recombination and reduced energy loss in PSCs. As a result, the champion power conversion efficiency (PCE) of PSCs can be significantly enhanced from 22.82% to 24.07%. Moreover, the unencapsulated device with CCC modification retains 92.0% of its original PCE even subject to thermal aging at 85 °C for 2496 h. This work provides guidance for the rational design of functional molecules as defect passivators in PSCs, which is beneficial for the improvements in both device performance and stability.

The domain boundaries act as interface barriers to bulk ionic conductivity in La2/3−xLi3xTiO3. Here we reveal for the first time the domain boundary structure plays a dominant role in determining the bulk conductivity, instead of domain boundary concentration.

Recently, surface passivation has been proved to be an essential approach for obtaining efficient and stable perovskite light-emitting diodes (Pero-LEDs). Phosphine oxides performed well as passivators in many reports. However, the most commonly used phosphine oxides are insulators, which may inhibit carrier transport between the perovskite emitter and charge-transporter layers, limiting the corresponding device performance. Here, 2,7-bis(diphenylphosphoryl)-9,9′-spirobifluorene (SPPO13), a conductive molecule with two phosphine oxide functional groups, is introduced to modify the perovskite emitting layer. The bifunctional SPPO13 can passivate the nonradiative defects of perovskite and promote electron injection at the interface of perovskite emitter and electron-transporter layers. As a result, the corresponding Pero-LEDs obtain a maximum external quantum efficiency (EQE) of 22.3%. In addition, the Pero-LEDs achieve extremely high brightness with a maximum of around 190 000 cd/m2.

All-inorganic cesium lead halide perovskite (CsPbX_3; X = Cl, Br) nanocrystals (NCs) are synthesized via a modified hot injection method using 3-mercaptopropyltrimethoxysilane (MPTMS), together with oleic acid and oleylamine, for in situ passivation of the surface defects. The surface chemistry, revealed by Fourier transform infrared spectroscopy (FTIR) and x-ray photoelectron spectroscopy (XPS) techniques, shows an absence of Si-O-Si network and C-O groups on these in situ passivated CsPbX_3 NCs, denoted as InMP-CsPbX_3, which is in strong contrast to the counterpart NCs obtained via a postsynthesis exchange strategy. The x-ray diffraction (XRD) pattern indicates a lattice structure significantly strained from the cubic structure. The synthesis of these InMP-CsPbX_3 NCs is highly reproducible, and the colloids are stable in nonpolar solvents. The emission wavelength of CsPb(Cl/Br)_3 mixed halide perovskite NCs is tuned from 405 nm to 508 nm by reducing the nominal Cl/Br ratio, while the photoluminescence quantum yield (PLQY) is greatly enhanced over the whole spectral range. More importantly, the InMP-treatment is among the few strategies that are promising for electroluminescence in light-emitting diodes.

Full-spectrum photofixation of N2with remarkable NH3production rate of 228 μmol/(g·h) was achieved by W atoms doped Ti3C2TxMXene (W/Ti3C2Tx-U) catalyst without sacrificial agents at room temperature. The effects of W doping and ultrasonic intercalation of Ti3C2TxMXene were studied. Scanning transmission electron microscope, electron spin resonance spectra, X-ray photoemission spectroscopy, UV-Vis spectrophotometer, temperature programmed adsorption analyzer and density functional theory calculation were used to characterize the obtained catalysts. Results showed that Ti3C2TxMXene harvested ultraviolet-visible and near-infrared light to generate hot electrons. In addition, the doped W atoms played an effective role in adsorbing and activating N2molecules by donating electrons to the anti-bonding orbitalof N2molecules to elongate the bond length of N≡N.

Spiro-OMeTAD, one of the most widely used hole-transport materials (HTMs) in optoelectronic devices, typically requires chemical doping with a lithium compound (LiTFSI) to attain sufficient conductivity and efficient hole extraction. However, the doping step requires an activation process that comprises exposure of the blend films to an ambient atmosphere. Additionally, the lithium dopant induces crystallization, and its hygroscopic nature negatively impacts device performance and lifetime. Here we report a facile approach based on the incorporation of a low-cost alkylthiol additive (1-dodecanethiol, DDT) in the spiro-OMeTAD HTM. We discover that DDT provides a more efficient and controllable doping process with significantly reduced doping duration, enabling the HTM to achieve comparable performance before air activation. The coordination between DDT and LiTFSI increases the concentration of dopants in the HTM bulk, reduces their accumulation at interfaces, and enhances the structural integrity of the HTM under wetting, heat and light stress. We fabricate perovskite solar cells using DDT-treated spiro-OMeTAD as the HTM. Our best devices exhibit a certified power conversion efficiency of 23.1%. Furthermore, the devices can retain 90% of peak performance under continuous illumination for 1,000 h. Our findings represent an important step forward in the production of doped spiro-OMeTAD, as well as its reliable application and future device commercialization.

Background: Blue laser imaging (BLI) can provide useful information on colorectal laterally spreading tumors (LSTs) by visualizing the surface and vessel patterns in detail. The present research aimed to evaluate the diagnostic performance of BLI-combined JNET (Japan NBI Expert Team) classification for identifying LSTs. Methods: This retrospective, multicenter study included 172 LSTs consisted of 6 hyperplastic polyps/sessile serrated polyps, 94 low-grade dysplasias (LGD), 60 high-grade dysplasias (HGD), 6 superficial submucosal invasive (m-SMs) carcinomas, and 4 deep submucosal invasive carcinomas. The relationship between the JNET classification and the histologic findings of these lesions were then analyzed. Results: For all LSTs, non-experts and experts had a 79.7% and 90.7% accuracy for Type 2A (P= 0.004), a sensitivity of 94.7% and 96.8% (P= 0.718), and a specificity of 61.5% and 83.3% (P= 0.002) for prediction of LGD, respectively. The results also demonstrated 80.8% and 91.3% accuracy for Type 2B (P= 0.005), a sensitivity of 65.2% and 83.3% (P= 0.017), and a specificity of 90.6% and 96.2% (P= 0.097) for predicting HGD or m-SMs. For LST-granular (LST-G) lesions, Type 2A in experts had higher specificity (65.6% vs. 83.6%, P= 0.022) and accuracy (81.8% vs. 91.2%, P= 0.022). Type 2B in experts only had higher accuracy (82.5% vs. 92.0%, P= 0.019). However, no significant differences were noted for any comparisons between non-experts and experts for LST-non-granular (LST-NG) lesions. Conclusions: BLI combined with JNET classification was an effective method for the precise prediction of pathological diagnosis in patients with LSTs. Diagnostic performance of JNET classification by experts was better than that by non-experts for all examined LST or LST-G lesions when delineating between Type 2A and 2B, but there was no difference for the identification of LST-NG lesions by these two groups.

Sensitive and reliable X-ray detectors are essential for medical radiography, industrial inspection and security screening. Lowering the radiation dose allows reduced health risks and increased frequency and fidelity of diagnostic technologies for earlier detection of disease and its recurrence. Three-dimensional (3D) organic–inorganic hybrid lead halide perovskites are promising for direct X-ray detection – they show improved sensitivity compared to conventional X-ray detectors. However, their high and unstable dark current, caused by ion migration and high dark carrier concentration in the 3D hybrid perovskites, limits their performance and long-term operation stability. Here we report ultrasensitive, stable X-ray detectors made using zero-dimensional (0D) methylammonium bismuth iodide perovskite (MA3Bi2I9) single crystals. The 0D crystal structure leads to a high activation energy (Ea) for ion migration (0.46 eV) and is also accompanied by a low dark carrier concentration (~ 106cm−3). The X-ray detectors exhibit sensitivity of 10,620 µC Gyair−1cm−2, a limit of detection (LoD) of 0.62 nGyairs−1, and stable operation even under high applied biases; no deterioration in detection performance was observed following sensing of an integrated X-ray irradiation dose of ~23,800 mGyair, equivalent to > 200,000 times the dose required for a single commercial X-ray chest radiograph. Regulating the ion migration channels and decreasing the dark carrier concentration in perovskites provide routes for stable and ultrasensitive X-ray detectors.

•Crystal quality of perovskite was tuned by chlorine incorporation derived from PbCl2.•Crystal grains and PL lifetimes of perovskite films have been effectively improved.•21.30% Efficiency has been achieved for the methylammonium-free perovskite device.•A VOCof 1.18 V has been obtained due to the reduced non-radiation recombination.•The unsealed device demonstrated superior long-term ambient and thermal stability.

The light weight, good bending resistance and low production cost make flexible perovskite solar cells (PSCs) good candidates in wearable electronics, portable charger, remote power, and flying objects. High power conversion efficiency (PCE) plays a crucial role on obtaining the high mass specific power of flexible devices. However, the performance for flexible PSCs is still having a large room to be improved. Here, we added the 2-amino-5-cyanopyridine (ACP) molecule with a polar electron density distribution in the perovskite precursor solution to improve the performance of flexible PSCs. The cyano groups with electron-withdrawing ability are expected to passivate positively charged point defects, while amines with electron donating ability are expected to passivate negatively charged point defects in perovskite films. Thanks to the effective passivation of defects at the grain boundary and surface of perovskite films, the PCE of flexible PSCs is obviously increased from 16.9% to 18.0%. These results provide a universal approach to improve performance of flexible PSCs by healing the defects in perovskite films through electrostatic interactions.

Antimony (Sb) is regarded as an attractive anode material for sodium-ion batteries (SIBs) due to its high theoretical capacity of 660 mAh g–1. Combining Sb with carbonaceous materials has been considered as an effective way to resolve the serious volume expansion issues. Sb/C composites mainly consist of two types, that is, Sb confined inside a carbon matrix and Sb deposited on the surface of a carbon matrix, and both have shown superior sodium storage performance. However, which structure is more beneficial for achieving high electrochemical performance is still unclear. In this work, peapod-like Sb@C and corn-like C@Sb nanotubes are synthesized viaa nanoconfined galvanic replacement reaction and used as model materials for sodium storage to explore the above issue. When evaluated as anode materials for SIBs, the peapod-like Sb@C shows a higher rate capability and a significantly better long-term cycling stability compared to those of the corn-like C@Sb. Electrochemical analysis reveals that the peapod-like Sb@C exhibits faster Na+and electron transport kinetics and higher proportions of surface capacitive contributions. These results demonstrate the structural superiority of the nanoconfined structure and provide valuable information for the rational design and construction of Sb-based anode materials for high-performance electrochemical energy storage.

Commercialization of perovskite solar cells (PSCs) requires developing high-efficiency devices with good stability. Ionic defects existing in the perovskite layer can serve as nonradiative recombination centers to deteriorate the performance of PSCs and can introduce chemical degradation of the perovskite material introducing instability issues. Here, passivation molecules with various electron density distributions (EDD) are employed as an ideal model to reveal the role of EDD on defect passivation in perovskite thin films. Power conversion efficiency (PCE) exceeding 21% with good stability in humid air was obtained for planar PSCs with the 4-aminobenzonitrile (ABN) additive, higher than the reference PSCs with a PCE of 20.22%. The improved stability and performance features are attributed to the efficient passivation for charged defects in perovskites by adding ABN, which guarantees a smaller Urbach energy, longer carrier lifetime, and less traps in the perovskite films.

Highlights: The modification of perovskite precursor by a series of phosphoryl chloride molecules can indeed improve the performance of perovskite LEDs (Pero-LEDs). The bis(2-oxo-3-oxazolidinyl) phosphinic chloride can not only regulate the phase distribution by controlling the crystallization rate but also passivate the defects of the quasi-2D perovskite. Highly efficient and reproducible Pero-LEDs are achieved with an maximum external quantum efficiency (EQEmax) of 20.82% and an average EQE (EQEave) of around 20% on 50 devices. Abstract: Quasi-2D perovskites have attracted tremendous interest for application as light-emission layers in light-emitting diodes (LEDs). However, the heterogeneous n phase and non-uniform distribution still severely limit the further development of quasi-2D perovskite LEDs (Pero-LEDs). Meanwhile, the increased defect density caused by the reduced dimension and grain size induces non-radiative recombination and further deteriorates the device performance. Here, we found that a series of molecules containing phosphoryl chloride functional groups have noticeable enhancement effects on the device performance of quasi-2D Pero-LEDs. Then, we studied the modification mechanism by focusing on the bis(2-oxo-3-oxazolidinyl) phosphinic chloride (BOPCl). It is concluded that the BOPCl can not only regulate the phase distribution by decreasing the crystallization rate but also remain in the grain boundaries and passivate the defects. As a result, the corresponding quasi-2D Pero-LEDs obtained a maximum external quantum efficiency (EQEmax) of 20.82% and an average EQE (EQEave) of around 20% on the optimal 50 devices, proving excellent reproducibility. Our work provides a new selection of molecular types for regulating the crystallization and passivating the defects of quasi-2D perovskite films.

The δ subunit-containing GABAAreceptor [GABAA(δ)R], which is exclusively situated in the extrasynaptic space, has considerable influence on emotion and behavior. Although the expression of this receptor experiences dramatic fluctuation during postnatal development, it remains unknown whether it regulates emotion in a development-dependent manner. Here, by using mice with genetic deletion of GABAA(δ)R (knockout) and their wild-type littermates, we examined the role of GABAA(δ)R in regulating anxiety-like behavior, as measured with open field test (OFT) and elevated plus maze during the transition from puberty to adulthood. We observed that for female mice, the knockout ones at puberty but not adulthood showed increased anxiety-like behavior in the OFT relative to their wild-type littermates. However, such increase was not observed in elevated plus maze. For male mice, no between-genotype differences were observed in both tests at the above two developmental stages. Our results suggest that GABAA(δ)R preferentially affects the anxiety-like behavior in OFT in a development-dependent manner, but only in female mice.

SnTe has been regarded as an environment-friendly alternative of PbTe thermoelectrics, although its performance is limited by its high thermal conductivity, partly owing to its high carrier concentration. In SnTe + xAgSbSe2, we observe a significant decrease of the total thermal conductivity from 3.37 to 1.27 W m–1K–1at 850 K, even though the hole concentration is at a high level of 1021cm–3. With the increase of the AgSbSe2fraction, both the electrical and thermal conductivities decrease to their minima at x= 20%, and then they start to increase simultaneously, indicating strong electron–phonon coupling. By applying the first-principles calculations, it is unraveled that the minimum of thermal conductivity is due to the nonmonotonic dependence of electron–phonon coupling on the lattice constant. At x= 20%, a ZTvalue of 0.95 at 850 K is achieved, accompanied by an ultralow lattice thermal conductivity. This study reveals that tuning the electron–phonon coupling could be an efficient way to improve the thermoelectric performance, if it is constrained within the process of intravalley scattering.

Despite incredible success has been achieved for perovskite solar cells (PSCs) in pursuing high power conversion efficiency (PCE), their practical application is prevented by the low stability issues, especially an accelerating stability test at high temperature still needs to be demonstrated. Herein, we present an inverted mesoscopic PSCs with Zn2+doped CuGaO2(Zn:CuGaO2) as both the scaffold and hole transporting materials (HTM). Both theoretical and experimental results indicate that the carrier density and conductivity of CuGaO2is significantly improved via Zn2+doping, which is beneficial for the hole transfer. Moreover, the mesoporous structure combined with the well matched energy levels between Zn:CuGaO2and perovskite can effectively extract holes from perovskite, reduce charge transfer barrier, and depress the charge-carrier recombination. As a result, the champion device with Zn:CuGaO2as HTM gives a power conversion efficiency of 20.67% from reverse scan and a stabilized efficiency of 20.15%, which is among the best results for PSCs based on methylammonium-free, cesium-formamidinium (Cs-FA) double-cation perovskite and inorganic HTM. Moreover, PCE of the unencapsulated device retains over 85% after thermal annealing at 85 °C for 1000 h in a nitrogen atmosphere, demonstrating the superior thermal stability of the present PSCs with the metal doped inorganic HTM.

One-dimensional nanotubes are very useful for achieving excellent performance in lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) due to the fact that tubular structures can effectively alleviate the structural strain and shorten the ion diffusion length during repeated cycling. In this work, we report a Cu2Sb-mediated growth strategy to controllably fabricate highly uniform Sb nanotubes (NTs), as well as Cu@Cu2Sb and Cu2Sb@Sb composite NTs, viaa facile galvanic replacement reaction using Cu nanowires (NWs) as sacrificial templates. Benefiting from their structural merits, the Sb NTs manifest excellent sodium storage performance with superior rate performance (286 mAh g–1at 10 A g–1) and extraordinary cycling stability (342 mAh g–1after 6000 cycles at 1 A g–1). Furthermore, a full cell with Sb NTs as anode and Na3(VOPO4)2F as cathode exhibits a high energy density (252 Wh kg–1) and high output voltage (2.7 V), revealing their significant application promise in the next-generation SIBs.

Metabotropic glutamate receptor 2 (mGlu2) belongs to the group-II metabotropic glutamate (mGlu) receptors and is a neurotransmitter G protein-coupled receptor. The group-II mGlu receptors are promising antipsychotic targets, but the specific role of mGlu2 signaling remains unclear. Receptor tyrosine kinases (RTKs) are also believed to participate in brain pathogenesis. To investigate whether there is any communication between mGlu2 and RTKs, we generated a CHO-mGlu2 cell line that stably expresses mGlu2 and showed that activation of mGlu2 by LY379268, a group II mGlu agonist, was able to transactivate insulin-like growth factor 1 receptor (IGF-1R). We further determined that the Gi/oprotein, Gβγsubunits, phospholipase C, and focal adhesion kinase (FAK) were involved in the IGF-1R transactivation signaling axis, which further induced the phosphorylation of extracellular signal-regulated kinase1/2 (ERK1/2) and cAMP response element-binding protein. In primary mouse cortical neurons, similar signaling pathways were observed when mGlu2 were stimulated by LY487379, an mGlu2 positive allosteric modulator. Transactivation of IGF-1R through FAK in response to mGlu2 should provide a better understanding of the association of mGlu2 with brain disease.

The single-crystal to single-crystal (SCSC) conversion of metal–organic frameworks (MOFs) represents a facile route to new MOFs with structures and functionalities that are challenging to obtain by direct synthesis. However, conversion products are often structurally limited for a given precursor. We herein report that a two-dimensional (2D) MOF featuring a linear Cd3cluster secondary building unit (SBU) converts into one type of three-dimensional (3D) interpenetrated and two types of 3D non-interpenetrated MOFs upon reaction with dipyridyl ligands. One of the interpenetrated 3D MOFs, in turn, undergoes either ligand substitution to give isoreticular interpenetrated MOFs, or ligand addition to give a self-penetrated 3D MOF. This rich SCSC conversion library is made possible by the inclined nature of the Cd3SBU with respect to the 2D plane of the starting material to create an anisotropic environment around the SBU.

Hierarchical nanosheet-based nanotubes are very attractive because their unique structure endows them with large surface areas and exposes massive active sites for functional applications. We herein demonstrate a facile one-pot hydrothermal approach to fabricate the hierarchical nanosheet-based MS2(M = Re, Mo, W) nanotubes by using Te nanowires as sacrificial templates. The hierarchical nanotubes show tube channels of ∼30 nm and hierarchical channel walls with a tunable thickness of up to ∼50 nm. As exemplified for application in Li-ion and Na-ion batteries, the ReS2hierarchical nanotubes exhibit excellent specific capacities (1137 mA h g–1for Li-ion batteries and 375 mA h g–1for Na-ion batteries at 0.1 A g–1after 100 cycles), good cycling stabilities, and high rate capabilities, demonstrating their promising applicability in rechargeable batteries. This work may open up new opportunities for further exploration of new types of hierarchical nanostructures for applications, e.g., in catalysis, energy chemistry, and gas adsorption and separation.