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Ion exchange membranes (IEMs) play a critical role in aqueous organic redox flow batteries (AORFBs). Traditional IEMs that feature microphase‐separated microstructures are well‐developed and easily available but suffer from the conductivity/selectivity tradeoff. The emerging charged microporous polymer membranes show the potential to overcome this tradeoff, yet their commercialization is still hindered by tedious syntheses and demanding conditions. We herein combine the advantages of these two types of membrane materials via simple in situ hypercrosslinking of conventional IEMs into microporous ones. Such a concept is exemplified by the very cheap commercial quaternized polyphenylene oxide membrane. The hypercrosslinking treatment turns poor‐performance membranes into high‐performance ones, as demonstrated by the above 10‐fold selectivity enhancement and much‐improved conductivities that more than doubled. This turn is also confirmed by the effective and stable pH‐neutral AORFB with decreased membrane resistance and at least an order of magnitude lower capacity loss rate. This battery shows advantages over other reported AORFBs in terms of a low capacity loss rate (0.0017 % per cycle) at high current density. This work provides an economically feasible method for designing AORFB‐oriented membranes with microporosity. [ABSTRACT FROM AUTHOR]

NaAsO2-induced liver damage leads to autophagy, which plays an important role in cell quality control. Mitophagy plays an important role in hepatocyte damage, and PINK1 and Parkin constitute an important pathway in mitophagy. PINK1 selectively degrades abnormal mitochondria, and Parkin can recognize damaged mitochondria. However, the mechanism underlying the involvement of PINK1/Parkin in NaAsO2-induced mitophagy is unclear. Transfection plasmids containing dsRNA were used to interfere with the expression of Parkin in the following groups: the empty plasmid group was established by add the empty plasmid only, the PINK1-knockdown (KD) group was established by adding 5 μg of PINK1 dsRNA and then by adding 10 mM NaAsO2, and the Parkin-KD group was established by adding 5 μg of Parkin dsRNA and then by adding 10 mM NaAsO2. The expression of PINK1 and Parkin in autophagy was detected by western blotting and immunofluorescence staining. The ultrastructures of autophagosomes and mitochondria were observed by transmission electron microscopy. The successful KD of PINK1 and Parkin aggravated the NaAsO2-induced damage to mitophagy. The degeneration of mitochondrial vacuoles and the appearance of autophagosomes were detected in the NaAsO2, NaAsO2 + PINK1-KD and NaAsO2 + Parkin-KD groups. NaAsO2 can induce mitophagy in rat hepatocytes, and the silencing of PINK1 and Parkin can aggravate mitochondrial damage during this process. This study explored the mechanism of NaAsO2-induced mitophagy in BRL-3A cells after PINK1 and Parkin gene silencing. [ABSTRACT FROM AUTHOR]

Zinc–iodine (Zn−I2) batteries are gaining popularity due to cost‐effectiveness and ease of manufacturing. However, challenges like polyiodide shuttle effect and Zn dendrite growth hinder their practical application. Here, we report a cation exchange membrane to simultaneously prevent the polyiodide shuttle effect and regulate Zn2+ deposition. Comprised of rigid polymers, this membrane shows superior swelling resistance and ion selectivity compared to commercial Nafion. The resulting Zn−I2 battery exhibits a high Coulombic efficiency of 99.4 % and low self‐discharge rate of 4.47 % after 48 h rest. By directing a uniform Zn2+ flux, the membrane promotes a homogeneous electric field, resulting in a dendrite‐free Zn surface. Moreover, its microporous structure enables pre‐adsorption of additional active materials prior to battery assembly, boosting battery capacity to 287 mAh g−1 at 0.1 A g−1. At 2 A g−1, the battery exhibits a steady running for 10,000 cycles with capacity retention up to 96.1 %, demonstrating high durability of the membrane. The practicality of the membrane is validated via a high‐loading (35 mg cm−2) pouch cell with impressive cycling stability, paving a way for membrane design towards advanced Zn−I2 batteries. [ABSTRACT FROM AUTHOR]

Membranes which allow fast and selective transport of protons and cations are required for a wide range of electrochemical energy conversion and storage devices, such as proton-exchange membrane (PEM) fuel cells (PEMFCs) and redox flow batteries (RFBs). Herein we report a new approach to designing solution-processable ion-selective polymer membranes with both intrinsic microporosity and ion-conductive functionality. Polymers are synthesized with rigid and contorted backbones, which incorporate hydrophobic fluorinated and hydrophilic sulfonic acid functional groups, to produce membranes with negatively charged subnanometer-sized confined ionic channels. The ready transport of protons and cations through these membranes, and the high selectivity towards nanometer-sized redox-active molecules, enable efficient and stable operation of an aqueous alkaline quinone redox flow battery and a hydrogen PEM fuel cell., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)