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For the state-of-the-art quantum dot light-emitting diodes, while the ZnO nanoparticle layers can provide effective electron injections into quantum dots layers, the hole transporting materials usually cannot guarantee sufficient hole injection owing to the deep valence band of quantum dots. Developing proper hole transporting materials to match energy levels with quantum dots remains a great challenge to further improve the device efficiency and operation lifetime. Here we demonstrate high-performance quantum dot light-emitting diodes with much extended operation lifetime using quantum dots with tailored energy band structures that are favorable for hole injections. These devices show a T 95 operation lifetime of more than 2300 h with an initial brightness of 1000 cd m −2 , and an equivalent T 50 lifetime at 100 cd m −2 of more than 2,200,000 h, which meets the industrial requirement for display applications. The commercialization of light-emitting diodes based on emissive quantum dots (e.g. QLEDs) is hindered by their inherent poor operational lifetime. Using an intelligent energy-level design strategy, Qian et al. demonstrate QLEDs with operational lifetime that meets industrial display standards.

Solid polymer electrolytes (SPEs), which are favorable to form intimate interfacial contacts with electrodes, are promising electrolyte of choice for long-cycling lithium metal batteries (LMBs). However, typical SPEs with easily oxidized oxygen-bearing polar groups exhibit narrow electrochemical stability window (ESW), making it impractical to increase specific capacity and energy density of SPE based LMBs with charging cut-off voltage of 4.5 V or higher. Here, we apply a polyfluorinated crosslinker to enhance oxidation resistance of SPEs. The crosslinked network facilitates transmission of the inductive electron-withdrawing effect of polyfluorinated segments. As a result, polyfluorinated crosslinked SPE exhibits a wide ESW, and the Li|SPE|LiNi 0.5 Co 0.2 Mn 0.3 O 2 cell with a cutoff voltage of 4.5 V delivers a high discharge specific capacity of ~164.19 mAh g −1 at 0.5 C and capacity retention of ~90% after 200 cycles. This work opens a direction in developing SPEs for long-cycling high-voltage LMBs by using polyfluorinated crosslinking strategy. Solid polymer electrolytes are commonly used in lithium-metal batteries, but their capacity and energy density cannot be easily increased beyond a charging cut-off voltage of 4.5 V due to the presence of easily oxidized oxygen-bearing polar groups. Here, authors apply a polyfluorinated crosslinker to enhance the oxidation resistance to solve this issue

Tin perovskite is rising as a promising candidate to address the toxicity and theoretical efficiency limitation of lead perovskite. However, the voltage and efficiency of tin perovskite solar cells are much lower than lead counterparts. Herein, indene-C 60 bisadduct with higher energy level is utilized as an electron transporting material for tin perovskite solar cells. It suppresses carrier concentration increase caused by remote doping, which significantly reduces interface carriers recombination. Moreover, indene-C 60 bisadduct increases the maximum attainable photovoltage of the device. As a result, the use of indene-C 60 bisadduct brings unprecedentedly high voltage of 0.94 V, which is over 50% higher than that of 0.6 V for device based on [6,6]-phenyl-C61-butyric acid methyl ester. The device shows a record power conversion efficiency of 12.4% reproduced in an accredited independent photovoltaic testing lab. Despite the lower device efficiency, tin perovskite based solar cells are preferred choices compared to lead-based counterparts due to much lower toxicity. Here Jiang et al. use a fullerene derivative to greatly suppress carrier interface recombination and obtain record high cell efficiency of 12%.

The electrocatalytic valorization of polyethylene terephthalate-derived ethylene glycol to valuable glycolic acid offers considerable economic and environmental benefits. However, conventional methods face scalability issues due to rapid activity decay of noble metal electrocatalysts. We demonstrate that a dynamic potential cycling approach, which alternates the electrode potential between oxidizing and reducing values, significantly mitigates surface deactivation of noble metals during electrochemical oxidation of ethylene glycol. This method enhances catalyst activity by 20 times compared to a constant-potential approach, maintaining this performance for up to 60 h with minimal deactivation. In situ Raman and X-ray absorption spectroscopy show that this effectiveness results from efficient removal of surface oxide during the reaction. The strategy is applicable to polyethylene terephthalate hydrolysates and various noble metals, such as palladium, gold, and platinum, with palladium showing a high conversion rate in recent studies. Our approach offers an efficient and durable method for electrochemical upcycling of biomass-derived compounds. The value-added electrochemical conversion of ethylene glycol using noble metal catalysts is often hindered by rapid deactivation. In this study, the authors present a dynamic potential cycling method that effectively suppresses oxide-induced deactivation and enhances both catalyst activity and stability.

The insertion of an insulating layer into a multilayer light-emitting diode (LED) based on quantum dots and produced by depositing the layers from solution increases the performance of the LEDs to levels comparable to those of state-of-the-art organic LEDs produced by vacuum deposition, while retaining the advantages of solution processing. Efficient LEDs made from solution Light-emitting diodes (LEDs) form the basis of many modern display and solid-state lighting technologies. LEDs that can be processed from solution are especially appealing as they offer the potential for low-cost, large-area fabrication on a variety of substrates. Solution-processed diodes are generally less efficient that their vacuum-deposited counterparts, but Xiaogang Peng and colleagues now show how subtle changes in device architecture can be used to enhance the performance of solution-processed quantum-dot LEDs. By inserting an insulating layer into a solution-processed multilayer LED, the authors achieve performance levels comparable to those of state-of-the-art organic LEDs produced by vacuum deposition, while retaining the advantages of solution processing. Solution-processed optoelectronic and electronic devices are attractive owing to the potential for low-cost fabrication of large-area devices and the compatibility with lightweight, flexible plastic substrates. Solution-processed light-emitting diodes (LEDs) using conjugated polymers or quantum dots as emitters have attracted great interest over the past two decades 1 , 2 . However, the overall performance of solution-processed LEDs 2 , 3 , 4 , 5 —including their efficiency, efficiency roll-off at high current densities, turn-on voltage and lifetime under operational conditions—remains inferior to that of the best vacuum-deposited organic LEDs 6 , 7 , 8 . Here we report a solution-processed, multilayer quantum-dot-based LED with excellent performance and reproducibility. It exhibits colour-saturated deep-red emission, sub-bandgap turn-on at 1.7 volts, high external quantum efficiencies of up to 20.5 per cent, low efficiency roll-off (up to 15.1 per cent of the external quantum efficiency at 100 mA cm −2 ), and a long operational lifetime of more than 100,000 hours at 100 cd m −2 , making this device the best-performing solution-processed red LED so far, comparable to state-of-the-art vacuum-deposited organic LEDs 2 , 3 , 4 , 5 , 6 , 7 , 8 . This optoelectronic performance is achieved by inserting an insulating layer between the quantum dot layer and the oxide electron-transport layer to optimize charge balance in the device and preserve the superior emissive properties of the quantum dots. We anticipate that our results will be a starting point for further research, leading to high-performance, all-solution-processed quantum-dot-based LEDs ideal for next-generation display and solid-state lighting technologies.

Aqueous polysulfide/iodide redox flow batteries are attractive for scalable energy storage due to their high energy density and low cost. However, their energy efficiency and power density are usually limited by poor electrochemical kinetics of the redox reactions of polysulfide/iodide ions on graphite electrodes, which has become the main obstacle for their practical applications. Here, CoS 2 /CoS heterojunction nanoparticles with uneven charge distribution, which are synthesized in situ on graphite felt by a one-step solvothermal process, can significantly boost electrocatalytic activities of I − /I 3 − and S 2− /S x 2− redox reactions by improving absorptivity of charged ions and promoting charge transfer. The polysulfide/iodide flow battery with the graphene felt-CoS 2 /CoS heterojunction can deliver a high energy efficiency of 84.5% at a current density of 10 mA cm −2 , a power density of 86.2 mW cm −2 and a stable energy efficiency retention of 96% after approximately 1000 h of continuous operation. Polysulfide/iodide redox flow batteries are promising due to low cost and high-solubility components, but are limited by energy efficiency and power density. Here the authors fabricate heterojunction electrocatalysts to achieve improved performance in a polysulfide/iodide redox flow battery.

Charged defects at the surface of the organic–inorganic perovskite active layer are detrimental to solar cells due to exacerbated charge carrier recombination. Here we show that charged surface defects can be benign after passivation and further exploited for reconfiguration of interfacial energy band structure. Based on the electrostatic interaction between oppositely charged ions, Lewis-acid-featured fullerene skeleton after iodide ionization (PCBB-3N-3I) not only efficiently passivates positively charged surface defects but also assembles on top of the perovskite active layer with preferred orientation. Consequently, PCBB-3N-3I with a strong molecular electric dipole forms a dipole interlayer to reconfigure interfacial energy band structure, leading to enhanced built-in potential and charge collection. As a result, inverted structure planar heterojunction perovskite solar cells exhibit the promising power conversion efficiency of 21.1% and robust ambient stability. This work opens up a new window to boost perovskite solar cells via rational exploitation of charged defects beyond passivation. Charged surface defects are expected to undermine the charge extraction in organic-inorganic perovskite solar cells. Here Zhang et al. design ionic fullerene derivatives to not only passivate the charged defects, but also optimize the interfacial energy due to aligned orientation of the fullerenes.

Stable solid electrolyte interface (SEI) is highly sought after for lithium metal batteries (LMB) owing to its efficient electrolyte consumption suppression and Li dendrite growth inhibition. However, current design strategies can hardly endow a multifunctional SEI formation due to the non-uniform, low flexible film formation and limited capability to alter Li nucleation/growth orientation, which results in unconstrained dendrite growth and short cycling stability. Herein, we present a novel strategy to employ electrolyte additives containing catechol and acrylic groups to construct a stable multifunctional SEI by in-situ anionic polymerization. This self-smoothing and robust SEI offers multiple sites for Li adsorption and steric repulsion to constrain nucleation/growth process, leading to homogenized Li nanosphere formation. This isotropic nanosphere offers non-preferred Li growth orientation, rendering uniform Li deposition to achieve a dendrite-free anode. Attributed to these superiorities, a remarkable cycling performance can be obtained, i.e., high current density up to 10 mA cm −2 , ultra-long cycle life over 8500 hrs operation, high cumulative capacity over 4.25 Ah cm −2 and stable cycling under 60 °C. A prolonged lifespan can also be achieved in Li-S and Li-LiFePO 4 cells under lean electrolyte content, low N/P ratio or high temperature conditions. This facile strategy also promotes the practical application of LMB and enlightens the SEI design in related fields. Stable solid electrolyte interface (SEI) is heavily investigated due to its role in improving lithium metal batteries. Here, the authors present a new strategy by employing electrolyte additives to construct stable multifunctional SEI via in situ anionic polymerization.

This systematic review aimed to evaluate the long-term (≥ 5 years) outcomes of bariatric surgery on diabetes remission, microvascular and macrovascular events, and mortality among type 2 diabetes (T2D) patients. Ten articles (one randomized controlled trial and nine cohorts) met the inclusion criteria and were included in this review. Pooled estimates of nine cohort studies showed that surgery significantly increased the diabetes remission (relative risk (RR) = 5.90; 95% CI 3.75–9.28), reduced the microvascular (RR = 0.37; 95% CI = 0.30–0.46) and macrovascular events (RR = 0.52; 95% CI 0.44–0.61), and mortality (RR = 0.21; 95% CI 0.20–0.21) as compared to non-surgical treatment. Available evidence suggests better remission and lower risks of microvascular and macrovascular disease and mortality in the surgery group as compared to non-surgical treatment group in T2D patients after at least 5 years of follow-up.

The quest for efficient non-Pt/Pd catalysts has proved to be a formidable challenge for auto-exhaust purification. Herein, we present an approach to construct a robust catalyst by embedding single-atom Ru sites onto the surface of CeO 2 through a gas bubbling-assisted membrane deposition method. The formed single-atom Ru sites, which occupy surface lattice sites of CeO 2 , can improve activation efficiency for NO and O 2 . Remarkably, the Ru 1 /CeO 2 catalyst exhibits exceptional catalytic performance and stability during auto-exhaust carbon particle oxidation (soot), rivaling commercial Pt-based catalysts. The turnover frequency (0.218 h −1 ) is a nine-fold increase relative to the Ru nanoparticle catalyst. We further show that the strong interfacial charge transfer within the atomically dispersed Ru active site greatly enhances the rate-determining step of NO oxidation, resulting in a substantial reduction of the apparent activation energy during soot oxidation. The single-atom Ru catalyst represents a step toward reducing dependence on Pt/Pd-based catalysts. Here, the authors report a study exploring surface lattice-confined single-atom ruthenium sites which demonstrate remarkable stability and exceptional catalytic performance for auto-exhaust purification, making them a promising alternative to costly Pt/Pd-based catalysts.