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Light‐emitting diodes (LEDs) based on perovskite quantum dots (QDs), abbreviated as P‐QLEDs have been regarded as significantly crucial emitters for lighting and displays. Efficient and stable P‐QLEDs still lack ideal electron transport materials (ETM), which could efficiently block hole, transport electron, reduce interface non‐radiative recombination and possess high thermal stability. Here, we report 2,4,6‐Tris(3′‐(pyridine‐3‐yl) biphenyl‐3‐yl)‐1,3,5‐triazine (TmPPPyTz, 3P) with strong electron‐withdrawing moieties of pyridine and triazine to modulate the performance of P‐QLEDs. Compared with commonly used 1,3,5‐Tris(1‐phenyl‐1H‐benzimidazol‐2‐yl)benzene (TPBi), the pyridine in 3P have a strong interaction with perovskites, which can effectively suppress the interface non‐radiative recombination caused by the Pb2+ defects on the surface of QDs. In addition, 3P have deep highest occupied molecular orbital (HOMO) (enhancing hole‐blocking properties), matched lowest unoccupied molecular orbital (LUMO) and excellent electron mobility (enhancing electron transport properties), realizing the carrier balance and maximizing the exciton recombination. Furthermore, high thermal resistance of 3P obviously improves the stability of QDs under variable temperature, continuous UV illumination, and electric field excitation. Resultantly, the P‐QLEDs using the 3P as ETM achieved an outstanding performance with a champion EQE of 30.2 % and an operational lifetime T50 of 3220 hours at an initial luminance of 100 cd m−2, which is 151 % and about 11‐fold improvement compared to control devices (EQE=20 %, T50=297 hours), respectively. These results provide a new concept for constructing the efficient and stable P‐QLEDs from the perspective of selective ETM. [ABSTRACT FROM AUTHOR]

Perovskite quantum dot-based light-emitting diodes (QLEDs) have been considered as a promising luminescent technology due to high color purity and wide color gamut. However, the realization of high-performance QLED is still hindered by near-perfect quantum dots (QDs) with efficient and stable exciton recombination behavior. Here, we proposed a ligand compensation (LC) strategy to optimize the QDs by introducing a ligand pair of tri-n-octylphosphine (TOP) and CsBr. The ligand pair could enhance the clarity and colloidal stability of the QD ink, facilitating the fabrication of highly smooth films. On one hand, TOP engages in interactions with Pb and effectively passivates the surface uncoordinated Pb2+. On the other hand, the supplement of CsBr provides a Br-rich environment to reduce Br vacancies (VBr). Through LC, QD films possess a high photoluminescence quantum efficiency of 82% and a shallow hole level, which enables efficient exciton recombination. In addition, the LC makes QD films exhibit stable exciton combination behavior and electrical transport characteristics. Resultantly, the LC-optimized QLEDs show a maximum external quantum efficiency (EQE) of 24.7% and an operational lifetime T50 of 182 h at an initial luminance of 100 cd m−2, which is obviously higher than that of the control device (EQE of 15.8%, T50 of 11 h). The proposed LC strategy for optimizing perovskite QDs presents a novel concept for achieving high-performance QLEDs and holds great potential for widespread application in various optoelectronics. [ABSTRACT FROM AUTHOR]

The traditional packaging concept has reached its limits when it comes to ensuring the quality of food and extending its shelf life. Compared to traditional packaging materials, food packaging with self-healing function is becoming more and more popular. This is because they can automatically repair the damaged area, restore the original properties and prevent the decline of food quality and loss of nutrients. Materials based on various self-healing mechanisms have been developed and used on a laboratory scale in the form of coatings and films for food packaging. However, more efforts are needed for the commercial application of these new self-healing packaging materials. Understanding the self-healing mechanism of these packaging materials is very important for their commercial application. This article first discusses the self-healing mechanism of different packaging materials and compares the self-healing efficiency of self-healing materials under different conditions. Then, the application potential of self-healing coatings and films in the food industry is systematically analyzed. Finally, we give an outlook on the application of self-healing materials in the field of food packaging. [ABSTRACT FROM AUTHOR]

Food spoilage caused by foodborne microorganisms will not only cause significant economic losses, but also the toxins produced by some microorganisms will also pose a serious threat to human health. Essential oil (EOs) has significant antimicrobial activity, but its application in the field of food preservation is limited because of its volatile, insoluble in water and sensitive to light and heat. Therefore, in order to solve these problems effectively, this paper first analyzed the antibacterial effect of EOs as an antimicrobial agent on foodborne bacteria and its mechanism. Then, the application strategies of EOs as a sustained-release antimicrobial agent in food preservation were reviewed. On this basis, the release mechanism and application cases of EOs in different antibacterial composites were analyzed. The purpose of this paper is to provide technical support and solutions for the preparation of new antibacterial packaging materials based on plant active components to ensure food safety and reduce food waste. [ABSTRACT FROM AUTHOR]

Aqueous rechargeable batteries (ARBs) are generally safer than non-aqueous analogues, they are also less-expensive, and more friendly to the environment. However, the inherent disadvantage of the narrow electrochemical window of H2O seriously restricts the energy density and output voltage of ARBs, especially aqueous rechargeable Fe-based batteries. Herein, we introduce a new battery system: the anode contains C@Fe/Fe2O3 composite, which is interfaced with an alkaline electrolyte; the cathode contains LiMn2O4 in contact with a neutral electrolyte. A Li+-conducting membrane is carefully selected to decouple the electrode-electrolyte, which effectively widens the electrochemical window to above 2.65 V, thereby enables an aqueous rechargeable iron battery. Its average output voltage is 1.83 V and its energy density is 235.3 Wh/kg at 549 W/kg. In this work, we propose the energy storage mechanism with the aid of density functional theory (DFT). The calculated reduction potential of the anode agrees with the experimental value. Furthermore, this battery system demonstrates long cycle lifespan of approximately 2500 cycles at 2 A/g, corresponding to a capacity retention of 82.1%. These results are very far superior than those of mainstream aqueous rechargeable Fe-based batteries, which guarantee future investigation for storing electricity energy. [ABSTRACT FROM AUTHOR]