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A multi-functional ionogel modified perovskite film was fabricated in situ by a R2R-compatible fabrication method and an efficiency of 21.76% was achieved in flexible solar cells with excellent operational, mechanical and water-resistant stability.

Solution-processed organic‒inorganic halide perovskite (OIHP) single crystals (SCs) have demonstrated great potential in ionizing radiation detection due to their outstanding charge transport properties and low-cost preparation. However, the energy resolution (ER) and stability of OIHP detectors still lag far behind those of melt-grown inorganic perovskite and commercial CdZnTe counterparts due to the absence of detector-grade high-quality OIHP SCs. Here, we reveal that the crystallinity and uniformity of OIHP SCs are drastically improved by relieving interfacial stress with a facial gel-confined solution growth strategy, thus enabling the direct preparation of large-area detector-grade SC wafers up to 4 cm with drastically suppressed electronic and ionic defects. The resultant radiation detectors show both a small dark current below 1 nA and excellent baseline stability of 4.0×10− 8 nA cm− 1 s− 1 V− 1, which are rarely realized in OIHP detectors. Consequently, a record high ER of 4.9% at 59.6 keV is achieved under a standard 241Am gamma-ray source with an ultralow operating bias of 5 V, representing the best gamma-ray spectroscopy performance among all solution-processed semiconductor radiation detectors ever reported.

A novel photodynamic inactivation (PDI)-mediated antimicrobial film of polylactic acid/5-aminolevulinic acid (PLA/ALA) was successfully fabricated by a covalent grafting method using low-temperature plasma. The chemical structure, surface morphology, hydrophilic ability, and mechanical and barrier properties of the films were characterized, and their antibacterial, anti-biofilm potency and preservation effects on ready-to-eat salmon were investigated during storage. Results showed that the amino group of ALA was covalently grafted with the carboxyl group on the surface of PLA after the plasma treatment, with the highest grafting rate reaching ∼50%. The fabricated PLA/ALA films displayed an enhanced barrier ability against water vapor and oxygen. Under blue light-emitting diode illumination, the PLA/ALA films generated massive reactive oxygen species from the endogenous porphyrins in cells induced by ALA and then fatally destroyed the cell wall of planktonic cells and the architectural structures of sessile biofilms of the pathogens (

Although seeking an effective strategy for further improving their optical properties is a great challenge, two-dimensional (2D) halide perovskites have attracted a significant amount of attention because of their performance. In this regard, the pressure-induced emission accompanied by a remarkable pressure-enhanced emission is achieved without a phase transition in 2D vacancy-ordered perovskite Cs

Low-dimensional hybrid lead-halide perovskites with broadband white-light emission upon near-UV excitation have attracted immense scientific interest due to their potential application for the next...

Here, we show that flexible perovskite solar cells (PSCs) with high operational stability and power conversion efficiency (PCE) approaching 20% were achieved by elastic grain boundary (GB) encapsul...

Antibacterial packaging film mediated by photodynamic inactivation (PDI) is a new concept in food industry. The objective of this study was to fabricate a green 2,3-dialdehyde cellulose (DAC)-based antimicrobial film with PDI potency by incorporating the β-cyclodextrin/curcumin (β-CD/Cur) complex as a photosensitizer. The PDI-mediated films were characterized by evaluating the surface morphology, chemical structure, light transmittance, mechanical properties, photochemical and thermal stability, and water solubility. The results showed that the DAC-CD/Cur films were soluble in water and mechanically strong with a tensile strength of 63.87 MPa and an elongation break of 1.32%, which was attributed to the formation of hydrogen bonds between DAC and β-CD/Cur molecules. Meanwhile, the composite films possessed a good light transmittance but impeded the penetration of ultraviolet light and efficiently delayed the degradation of curcumin. More importantly, the PDI-mediated films exhibited a broad-spectrum ability to kill Listeria monocytogenes, Vibrio parahaemolyticus, and Shewanella putrefaciens in pure culture. Notably, they also potently inactivated these harmful bacteria on ready-to-eat salmon with a maximum of ∼4 Log CFU/g (99.99%) reduction after 60 min irradiation (13.68 J/cm2). Therefore, the PDI-mediated DAC-CD/Cur films are novel and promising antimicrobial food packaging films in food industry.

A highly crystalline tempered-glass-like perovskite grain structure with compressed surface lattice realized by a thermal-shocking fabrication is shown. The strained perovskite grain structure is stabilized by Cl

Lead-free Cs

In tumor tissue, basic fibroblast growth factor (bFGF) and vascular endothelial growth factor A (VEGFA) promote tumorigenesis by activating angiogenesis, but targeting single factor may produce drug resistance and compensatory angiogenesis. The Peptibody with bFGF/VEGFA was designed to simultaneously blockade these two factors. We were aiming to produce this Fc fusion protein in a large scale. The biological characterizations of Peptibody strains were identified as Escherichia coli and the fermentation mode was optimized in the shake flasks and 10‐L bioreactor. The fermentation was scaled up to 100 L, with wet cell weight (WCW) 126 g/L, production 1.41 g/L, and productivity 0.35 g/(L·h) of IPTG induction. The target protein was isolated by cation‐exchange, hydrophobic and Protein A chromatography, with total recovery of 60.28% and HPLC purity of 86.71%. The host cells protein, DNA, and endotoxin residues were within the threshold. In mouse model, immunization of Peptibody vaccine could significantly suppressed the tumor growth and angiogenesis, with inhibition rate of 57.73 and 39.34%. The Peptibody vaccine could elicit high‐titer anti‐bFGF and anti‐VEGFA antibodies, which inhibited the proliferation and migration of Lewis lung cancer cell cells by decreasing the Akt/MAPK signal pathways. Therefore, the Peptibody with bFGF/VEGFA might be used as a therapeutic tumor vaccine. The large‐scale process we developed could support its industrial production and pre‐clinical study in the future.

Defect density is one of the most significant characteristics of perovskite single crystals (PSCs) that determines their optical and electrical properties, but few strategies are available to tune this property. Here, we demonstrate that voltage regulation is an efficient method to tune defect density, as well as the optical and electrical properties of PSCs. A three-step carrier transport model of MAPbBr3 PSCs is proposed to explore the defect regulation mechanism and carrier transport dynamics via an applied bias. Dynamic and steady-state photoluminescence measurements subsequently show that the surface defect density, average carrier lifetime, and photoluminescence intensity can be efficiently tuned by the applied bias. In particular, when the regulation voltage is 20 V (electrical poling intensity is 0.167 V μm−1), the surface defect density of MAPbBr3 PSCs is reduced by 24.27%, the carrier lifetime is prolonged by 32.04%, and the PL intensity is increased by 112.96%. Furthermore, a voltage-regulated MAPbBr3 PSC memristor device shows an adjustable multiresistance, weak ion migration effect and greatly enhanced device stability. Voltage regulation is a promising engineering technique for developing advanced perovskite optoelectronic devices., Perovskite devices: Digital memories thrive by tuning out defects Innovative materials gaining favor as replacements for silicon solar cells can also be transformed into memory logic circuits using a new fabrication procedure. Lead halide perovskites can be turned into optoelectronic devices through low-cost solution depositions, but these approaches often leave numerous charge-trapping defects in the perovskite. Weili Yu from China’s Changchun Institute of Optics and colleagues have now developed a technique for modifying the defect population of perovskite crystals without requiring chemical additives. The team used probes to apply an electric field to the surface of a perovskite sample for helping move injected charges into defect sites with a high degree of control, which further modulated the optical and electrical properties of perovskite sample. Optimized defect populations enabled the perovskite to act as memristor device, capable of activating multiple resistance states.

The efficiency of perovskite solar cells (PSCs) has developed rapidly in recent years, but the stability has still lagged behind. The ion migration effect, especially from small methylammonium (MA) cations, is a main factor for stability issues, and the use of MA-free perovskites is one potential pathway to suppress ion migration. In this work, we reveal that there is a much lower valence band maximum (VBM) of −5.8 eV for the most studied MA-free perovskite FA0.83Cs0.17PbI2.7Br0.3, which is much different from that of traditional perovskites, and the huge energy level mismatch between perovskites and the hole transport layer (HTL) is a major factor in limiting the device performance of MA-free PSCs. It was found that doping the conjugated polyelectrolyte poly[(9,9-bis(3′-((N,N-dimethyl)-N-ethylammonium)-propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)] (PFN-Br) into the perovskite can significantly promote anode contact and result in better device performance as well as stability of FA0.83Cs0.17PbI2.7Br0.3 based MA-free PSCs in an inverted planar structure. PFN-Br increases the energy position of the VBM of perovskites and results in well-matched energy levels between the perovskite and HTL of poly[bis(4-phenyl) (2,4,6-trimethylphenyl) amine (PTAA). Carrier extraction and transportation are highly encouraged at the surface of PTAA/perovskite, and corresponding interface recombination is effectively suppressed. As a result, a 60 mV increase in VOC is achieved, and this promotes an excellent device efficiency of 20.32%. At the same time, the efficient device displays significant stability under continuous illumination and bias under MPP conditions, and could maintain 80% of its initial power conversion efficiency (PCE) under continuous operation under one sun illumination over 500 hours.

Flexible perovskite solar cells (FPSCs) have attracted great attention due to their advantageous traits such as low cost, portability, light-weight, etc. However, mechanical stability is still the weak point in their practical application. Herein, we prepared efficient FPSCs with remarkable mechanical stability by a dynamic thermal self-healing effect, which can be realized by the usage of a supramolecular adhesive. The supramolecular adhesive, which was obtained by random copolymerization of acrylamide and n-butyl acrylate, is amphiphilic, has a proper glass transition temperature and a high density of hydrogen-bond donors and receptors, providing the possibility of thermal dynamic repair of mechanical damage in FPSCs. The adhesive also greatly improves the leveling property of the precursor solution on the hydrophobic poly[bis(4-phenyl)(2,4,6-trimethylphenyl)]amine (PTAA) surface. PSCs containing this adhesive achieve more than a 20 % power conversion efficiency (PCE) on flexible substrates and a 21.99 % PCE on rigid substrates (certified PCE of 21.27 %), with improved electron mobility and reduced defect concentration.

Fabrication of organic-metal-halide perovskite micro-nano array structures draws attention to the potential application in polarized light, high-resolution X-ray imaging, light-emitting diodes, and lasers. However, it is still challenging to achieve the growth of controllable long-range ordered nanostructure arrays by chemical solution-based techniques. Herein, controllable epitaxial growth of long-range ordered micro-nano arrays on MAPbI

Organic-inorganic halide perovskites have exhibited bright prospects in high-sensitivity X-ray detection. However, they generally suffer from the severe field-driven polarization issue that remarkably deteriorates the detection performance. Here, it is demonstrated that the interfacial electrochemical reaction between Au electrodes and halogen in MAPbI3 single crystals (SCs) is the major source of the dark current polarization in the metal-semiconductor-metal (MSM)-structured perovskite X-ray detectors at the initial stage of biasing. By introducing the p- and n-type charge transport layers to isolate the electrodes from contacting the SC surface, the polarization is fully eliminated under a large electric field up to 1000 V cm-1 . Moreover, the resultant lateral p-i-n heterojunction suppresses the dark current of the devices by nearly 3 orders of magnitude as compared to the MSM counterparts and therefore enables a high sensitivity of 5.2 × 106 µC Gy-1air cm-2 and a record low X-ray detection limit down to 0.1 nGyair s-1 . The excellent biasing stability and sensitivity of the devices allow to prepare the linear detector arrays for X-ray imaging applications.

For the purpose of more accurate reliability of interconnection networks, the g-extra connectivity has been proposed by Fabrega et al. [Discrete Mathematics 155 (1996) 49–57]. Given a graph G and a positive integer g, the g-extra connectivity of G, say κ o ( g ) ( G ) , is the minimum cardinality of a vertex subset V ( S ) such that G − S is disconnected and every remaining component has at least g + 1 vertices. The g-extra diagnosability of G, denoted by t ˜ g ( G ) , is the maximum number of faulty vertices that the system can guarantee to identify under the condition that every fault-free component contains at least g + 1 vertices. In this paper, we first determine κ o ( g ) ( H F Q ( n ) ) = ( g + 1 ) n − ( g 2 ) + 2 for n ≥ 4 , 0 ≤ g ≤ n − 4 , where H F Q ( n ) is the n-dimensional hierarchical folded cube. Moreover, we establish t ˜ g ( H F Q ( n ) ) = ( g + 1 ) ( n + 1 ) − ( g 2 ) + 1 under the PMC model ( n ≥ 4 , 1 ≤ g ≤ n − 4 ) and under the MM* model ( n ≥ 7 , 1 ≤ g ≤ n − 3 4 ), respectively.

Background: 3,3,7,7-tetrakis (difluoramino) octahydro-1,5-dinitro-1,5-diazocine (HNFX), as an important oxidizer in propellants, has received much attention due to its high density and energy. However, there are many difficulties that need to be solved, such as complex synthetic processes, low product yield, high cost of raw materials and complicated purification. In the synthesis of HNFX, the intermediate named 1,5-bis (p-toluenesulfonyl)-3,7-dihydroxyoctahydro-1, 5-diazocine (gem-diol), is difficult to synthesize. Methods: A simple method was used to synthesize the gem-diol. This prepared gem-diol was characterized by FT-IR, 1H NMR, melting point and mass spectrometry. In order to increase the yield of gem-diol, response surface methodology (RSM) was introduced to optimize experimental conditions. Results: After the establishment of the model, the optimal conditions of synthesis were found to be 9.33h for reaction time, 6.13wt. % for the concentration of NaOH and 1.38:1 for ratio of ECH (p-toluenesulfonamide): TCA (epichlorohydrin). Under the optimal conditions, the experimental value and the predicted value of yield were 22.18% and 22.92%, respectively. Conclusion: 1,5-bis (p-toluenesulfonyl)-3,7-dihydroxyoctahydro-1,5-diazocine (gem-diol) can be synthesized using the low cost of chemical materials, including p-toluenesulfonamide, epichlorohydrin, sodium hydroxide and ethanol. Response surface methodology (RSM) is an effective method to optimize the synthesis process, thereby improving the yield of gem-diol.

This work aimed to develop and characterize a novel indicator film for monitoring fish freshness based on agar incorporated with natural dye extracted from Arnebia euchroma root (AEREs). The Fourier transform infrared spectroscopy results reflected that some new interactions have occurred between polymer matrix and natural dye. And the results of X-ray diffraction and scanning electron microscopy indicated that AEREs were well dispersed in the agar base film. A certain decrease was observed in water solubility, swelling ratio and elongation at break of colorimetric film but tensile strength, Young's modulus, water vapor permeability and water contact angle of colorimetric film were increased by addition of AEREs. The prepared indicator films were used as freshness labels in an application trial, which was conducted to monitor the freshness of Wuchang bream (Megalobrama amblycephala) under refrigeration (4 °C) and at room temperature (25 °C). The total volatile basic nitrogen (TVB-N) and total viable count (TVC) of fish sample were determined periodically, and the color change of freshness labels was recorded simultaneously. The results showed that the indicator film with lower content of AEREs demonstrated more conspicuous color change during fish spoilage. And the color response of freshness label was consistent with the spoilage threshold of TVC and TVB-N content in fish sample. Thus, these colorimetric indicator films could indicate the fish spoilage by visible color change. The developed colorimetric indicator film is expected to provide a convenient, non-destructive and visual method to estimate fish freshness during storage.

Although formamidinium lead iodide (FAPbI3) perovskite shows excellent prospects in the field of optoelectronics, it is limited by the conversion of the black perovskite phase (α-FAPbI3) to the yellow non-perovskite phase (δ-FAPbI3). Here, we first introduce diamine cations [EDBE, 2,2-(ethylenedioxy)bis(ethylamine)] into FAPbI3 for stable and efficient near-infrared perovskite light-emitting diodes (NIR PeLEDs). By rationally regulating the α/δ phase, we have successfully prepared a NIR PeLED with an external quantum efficiency (EQE) of ≤11.40%. In addition, the perovskite film has excellent stability and does not undergo any significant change after being in air for 270 days. These results show that the introduction of EDBE reduces the formation energy of α-FAPbI3 perovskite and the hydrogen bonds formed between adjacent EDBE molecules increase the stability of the perovskite devices. This work could help guide the phase transition mechanism of FAPbI3 and further improve the performance of LEDs.

Active packaging is an innovative and effective way to extend the shelf life of food, but few studies have focused on the effect of its active ingredients on food flavor. This study aimed to develop slow-release polylactic acid/polyhydroxyalkanoates (PLA/PHA) active packaging containing oregano essential oil (OEO) and investigate the effect of active composite packaging on the flavor and quality of pufferfish fillets. The plasticizing effect of OEO increased the elongation at break (EAB) of the films from 23.36% to 65.80%. The adsorption of montmorillonite (MMT) reduces the loss of OEO during processing. The amount of active substance (carvacrol) released from PLA/PHA/OEO/MMT film to pufferfish was 9.70 mg/kg. The pufferfish fillets packed in PLA/PHA/OEO/MMT film showed the slightest difference on the 8th day from the beginning of storage. The slow-release composite films could extend the shelf life of pufferfish fillets by 2-3 days at 4 °C ± 1 °C.