All‐inorganic lead halide perovskite quantum dots (IHP QDs) have great potentials in photodetectors. However, the photoresponsivity is limited by the low charge transport efficiency of the IHP QD ...layers. High‐performance phototransistors based on IHP QDs hybridized with organic semiconductors (OSCs) are developed. The smooth surface of IHP QD layers ensures ordered packing of the OSC molecules above them. The OSCs significantly improve the transportation of the photoexcited charges, and the gate effect of the transistor structure significantly enhances the photoresponsivity while simultaneously maintaining high Iphoto/Idark ratio. The devices exhibit outstanding optoelectronic properties in terms of photoresponsivity (1.7 × 104 A W−1), detectivity (2.0 × 1014 Jones), external quantum efficiency (67000%), Iphoto/Idark ratio (8.1 × 104), and stability (100 d in air). The overall performances of our devices are superior to state‐of‐the‐art IHP photodetectors. The strategy utilized here is general and can be easily applied to many other perovskite photodetectors.
High‐performance hybrid phototransistors based on all‐inorganic lead halide perovskite quantum dots and organic semiconductors are fabricated and characterized. Because of the outstanding properties of the materials, the gate‐tunable phototransistors exhibit significantly high performance, including photoresponsivity (≈1.7 × 104 A W−1), detectivity (≈2.0 × 1014 Jones), EQE (≈67000%), Iphoto/Idark ratio (≈8.1 × 104), and long‐term stability in air.
Though fluorescence‐tag‐based anti‐counterfeiting technology has distinguished itself with cost‐effective features and huge information loading capacity, the clonable decryption process of ...spatial‐resolved anti‐counterfeiting cannot meet the requirements for high‐security‐level anti‐counterfeiting. Herein, we demonstrate a spatial‐time‐dual‐resolved anti‐counterfeiting system based on new organic–inorganic hybrid halides BAPPZn2(ClyBr1−y)8 (BAPP=1,4‐bis(3‐ammoniopropyl)piperazinium, y=0–1) with ultra‐long room‐temperature phosphorescence (RTP). Remarkably, the afterglow lifetime can be facilely tuned by regulating the halide‐induced heavy‐atom effect and can be identified by the naked eyes or with the help of a simple machine vision system. Therefore, the short‐lived unicolor fluorescence and lasting‐time‐tunable RTP provide the prerequisites for unicolor‐time‐resolved anti‐counterfeiting, which lowers the decryption‐device requirements and further provides the design strategy of advanced portable anti‐counterfeiting technology.
A new zero‐dimensional Zn‐based metal halide with ultra‐long room‐temperature phosphorescence (RTP) is reported. The RTP lifetimes can be facilely regulated via halide engineering, paving the way for designing spatial‐time‐dual‐resolved anti‐counterfeiting materials.
•Interaction quality influences continuance intention via user satisfaction.•Environment quality influences continuance intention via user satisfaction.•Outcome quality does not affect user ...satisfaction and continuance intention.•User satisfaction influences continuance intention.•Inertia mediates the effects of the other factors on continuance intention.
Vendors of mobile communication applications/services (apps) aim at improve their designs to attract and retain users, and thus achieve the critical mass needed to ensure the success of their services. Despite the significant number of prior mobile service studies, few works have examined the effects of inertia and satisfaction on the users’ continuance intention with regard to specific mobile communication apps from a mobile-service-quality perspective. By integrating the mobile service quality framework, inertia, and user satisfaction, this study develops a model for interpreting the development of the continuance intention of users of mobile communication apps. Data collected from 238 users of such apps provided support for the model. The results indicated that interaction quality, environment quality, inertia, and user satisfaction are key determinants of continuance intention, while outcome quality is not. The theoretical and practical implications of this work are discussed.
High‐energy‐density lithium (Li) metal batteries suffer from a short lifespan owing to apparently ceaseless inactive Li accumulation, which is accompanied by the consumption of electrolyte and active ...Li reservoir, seriously deteriorating the cyclability of batteries. Herein, a triiodide/iodide (I3−/I−) redox couple initiated by stannic iodide (SnI4) is demonstrated to reclaim inactive Li. The reduction of I3− converts inactive Li into soluble LiI, which then diffuses to the cathode side. The oxidation of LiI by the delithiated cathode transforms cathode into the lithiation state and regenerates I3−, reclaiming Li ion from inactive Li. The regenerated I3− engages the further redox reactions. Furthermore, the formation of Sn mitigates the corrosion of I3− on active Li reservoir sacrificially. In working Li | LiNi0.5Co0.2Mn0.3O2 batteries, the accumulated inactive Li is significantly reclaimed by the reversible I3−/I− redox couple, improving the lifespan of batteries by twice. This work initiates a creative solution to reclaim inactive Li for prolonging the lifespan of practical Li metal batteries.
A triiodide/iodide (I3−/I−) redox couple is introduced with a SnI4 initiator to reclaim inactive Li. The reduction of I3− converts inactive Li into soluble LiI, and the oxidation of LiI by a delithiated cathode realizes the restoration of Li ion in cathode from inactive Li. The regenerated I3− by oxidation engages the further redox reactions.
Ag electrode is widely used in inverted perovskite solar cells (PSCs), but its easy reaction and corrosive nature with perovskite always induces severe stability issue. Here, from typical theory of ...metal anticorrosion, a chemical anticorrosion approach for Ag electrode in inverted PSCs through introducing 2‐mercaptobenzothiazole (MBT) as a corrosion inhibitor is reported. MBT can strongly bond to Ag and form a compact MBT‐Ag chain on Ag surface owing to its N atom in thiazolyl ring and exocyclic thiol groups. As a result, Ag anticorrosion ability is greatly enhanced by increasing the corrosion potential and decreasing the corrosion current, thus effectively inhibiting possible chemical reaction and corrosion between perovskite and Ag electrodes. PSCs containing MBT/Ag exhibit high efficiency of over 23% with good stability, retaining 95 ± 4.1% of initial efficiency after storage for 3800 h in glovebox. Importantly, resulting PSCs also show excellent thermal stability, maintaining 90 ± 1.8% of initial efficiency after aging for 900 h at 85 °C.
A chemical anticorrosion strategy is proposed to inhibit Ag electrode corrosion in inverted perovskite solar cells through introducing 2‐mercaptobenzothiazole (MBT) inhibitor. MBT can bond on Ag surface to inhibit Ag corrosion. Resulting devices exhibit >23% efficiency with good stability, retaining >90% of initial efficiency whether after N2 storage for 3800 h or 85 °C aging for 900 h.
Co-sensitization of two or more dyes with complementary absorption spectra on a semiconductor film is an effective approach to enhance the performance of a dye-sensitized solar cell (DSSC). Porphyrin ...sensitizer YD2-oC8 showed outstanding photovoltaic performance co-sensitized with an organic dye to cover the entire visible spectral region, 400-700 nm. To promote the light-harvesting capability beyond 700 nm, a porphyrin dimer (YDD6) was synthesized for a co-sensitized system. We report a systematic approach for engineering of molecular co-sensitization of TiO sub(2) films in a cocktail solution containing YD2-oC8, an organic dye (CD4) and YDD6 in a specific molar ratio to optimize the photovoltaic performance of the device. The resulting device showed panchromatic spectral features in the IPCE action spectrum in the region 400-700 nm attaining efficiencies of 75-80%; the spectrum is extended to the near-IR region attaining 40-45% in 700-800 nm region, giving J sub(SC)/mA cm super(-2) = 19.28, V sub(OC)/mV = 753, FF = 0.719, and eta = 10.4% under standard AM 1.5 G one-sun irradiation. This performance is superior to what is obtained from the individual single-dye devices and the two-dye co-sensitized systems. The shifts of TiO sub(2) potential upon dye uptake and the kinetics of charge recombination were examined through measurements of the charge extraction (CE) and intensity-modulated photovoltage spectroscopy (IMVS), respectively. Five co-sensitized systems were investigated to demonstrate that suppression of dye aggregation of YDD6 in the co-sensitized film is a key factor to further improve the device performance.
Lung adenocarcinoma (ADC) is the predominant histological type of lung cancer, and radiotherapy is one of the current therapeutic strategies for lung cancer treatment. Unfortunately, biological ...complexity and cancer heterogeneity contribute to radioresistance development. Karyopherin α2 (KPNA2) is a member of the importin α family that mediates the nucleocytoplasmic transport of cargo proteins. KPNA2 overexpression is observed across cancer tissues of diverse origins. However, the role of KPNA2 in lung cancer radioresistance is unclear. Herein, we demonstrated that high expression of KPNA2 is positively correlated with radioresistance and cancer stem cell (CSC) properties in lung ADC cells. Radioresistant cells exhibited nuclear accumulation of KPNA2 and its cargos (OCT4 and c‐MYC). Additionally, KPNA2 knockdown regulated CSC‐related gene expression in radioresistant cells. Next‐generation sequencing and bioinformatic analysis revealed that STAT1 activation and nuclear phospholipid scramblase 1 (PLSCR1) are involved in KPNA2‐mediated radioresistance. Endogenous PLSCR1 interacting with KPNA2 and PLSCR1 knockdown suppressed the radioresistance induced by KPNA2 expression. Both STAT1 and PLSCR1 were found to be positively correlated with dysregulated KPNA2 in radioresistant cells and ADC tissues. We further demonstrated a potential positive feedback loop between PLSCR1 and STAT1 in radioresistant cells, and this PLSCR1‐STAT1 loop modulates CSC characteristics. In addition, AKT1 knockdown attenuated the nuclear accumulation of KPNA2 in radioresistant lung cancer cells. Our results collectively support a mechanistic understanding of a novel role for KPNA2 in promoting radioresistance in lung ADC cells.
Nuclear KPNA2 promotes radioresistance and regulates cancer stem cell properties in lung adenocarcinoma cells. A loop between PLSCR1 and STAT1 is involved in KPNA2‐mediated radioresistance.
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•Ordered porous hierarchical TiO2 (hier-TiO2) was synthesized by sintering MOFs.•The scaffold of scattered distribution was prepared by hier-TiO2 nanostructures.•The crystallization ...of perovskite was controlled due to ordered porous hier-TiO2.•Grains with enlarged sizes were formed due to scaffold of scattered distribution.•PSCs with hier-TiO2 scaffold show higher efficiency and better stability.
A type of quasi-mesoscopic perovskite solar cells (QM-PSCs) with porous hierarchical TiO2 (hier-TiO2) nanostructures of scattered distribution as scaffold was investigated. The porous hier-TiO2 nanostructures were synthesized by sintering MIL-125(Ti) of metal-organic frameworks (MOFs) at 500°C in air and which were partly inherited from the ordered porosity of MIL-125(Ti). The ordered hier-TiO2 nanostructures were scattered on compact TiO2 layer to form a quasi-mesoscopic scaffold of scattered distribution, which can offer enough growth space for perovskite grains and promote the ordered growth of perovskite grains. The QM-PSCs shows a power conversion efficiency (PCE) of 16.56%, much higher than PCE (11.38%) of PSCs with conventional small TiO2 nanoparticles (npt-TiO2) as scaffold and PCE (6.07%) of planar PSCs with compact TiO2 layer. The PCEs of PSCs with hier-TiO2 and npt-TiO2 remain 47% and 22% of the initial PCE values aging for 30days in air, indicating that PSCs with hier-TiO2 scaffold shown better stability and moisture resistance. The enhanced performance of QM-PSCs is primarily attributed to the superior wettability quasi-mesoscopic scaffold with ordered porous hier-TiO2 nanostructures, which help to form the high quality perovskite film with better crystillinity and less pin-holes, and improve the contact properties between perovksite and electron transport layer.
Carbon nanotube (CNT) has been considered as an ideal cathode material for field emission application for a long time. To improve field emission properties, coating CNT films to form a composite ...cathode is an effective approach. However, few reports have studied and revealed the effect of coated layer thickness. Hence, in this study, we employed an Au layer to coat CNT cathodes with capability to precisely control the coated film thickness and systematically investigated the film thickness effect on field emission properties of the CNT composite field-emission devices. A nonmonotonic relationship between field emission performances and cathode film thickness was observed, and a high performance with a rather low turn-on field of 0.60 V/μm and an ultrahigh field enhancement factor near to 20000 was optimally demonstrated for the CNT composite cathode with an Au layer thickness of 3 nm. Based on experimental data and analysis, the nonmonotonic tendency was found mainly due to effective field emitter density, and the cathode conductivity works only for ultrathin films. Besides, the CNT composite cathode had good stability and uniformity for low heat contact resistant. The superior performance of the CNT cathode composited with a proper Au layer demonstrated potential applications in vacuum electronic devices and an optimized thickness of the coated layer was important for field emission enhancement of composite cathodes.
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•Screen-printed DWCNTs coated with controllable thicknesses of Au films act as the composite field emission cathodes.•The effective field emitter density is the main factor influencing the thickness dependent field emission performance.•Best performance of rather low Eto and Eth with an ultrahigh β is achieved for the cathode with an optimized Au layer thickness of 3 nm.•The conductivity of composite cathode only has a slight influence on field emission properties for thick films.
Gloeobacter rhodopsin (GR) is a cyanobacterial proton pump which can be potentially applied to optogenetics. We solved the crystal structure of GR and found that it has overall similarity to the ...homologous proton pump from Salinibacter ruber, xanthorhodopsin (XR). We identified distinct structural characteristics of GR's hydrogen bonding network in the transmembrane domain as well as the displacement of extracellular sides of the transmembrane helices relative to those of XR. Employing Raman spectroscopy and flash-photolysis, we found that GR in the crystals exists in a state which displays retinal conformation and photochemical cycle similar to the functional form observed in lipids. Based on the crystal structure of GR, we selected a site for spin labeling to determine GR's oligomerization state using double electron-electron resonance (DEER) spectroscopy and demonstrated the pH-dependent pentamer formation of GR. Determination of the structure of GR as well as its pentamerizing propensity enabled us to reveal the role of structural motifs (extended helices, 3-omega motif and flipped B-C loop) commonly found among light-driven bacterial pumps in oligomer formation. Here we propose a new concept to classify these pumps based on the relationship between their oligomerization propensities and these structural determinants.
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