In the brain, a reduction in extracellular osmolality causes water-influx and swelling, which subsequently triggers Cl − - and osmolytes-efflux via volume-regulated anion channel (VRAC). Although LRRC8 family has been recently proposed as the pore-forming VRAC which is activated by low cytoplasmic ionic strength but not by swelling, the molecular identity of the pore-forming swelling-dependent VRAC (VRAC swell ) remains unclear. Here we identify and characterize Tweety-homologs (TTYH1, TTYH2, TTYH3) as the major VRAC swell in astrocytes. Gene-silencing of all Ttyh1/2/3 eliminated hypo-osmotic-solution-induced Cl − conductance (I Cl,swell ) in cultured and hippocampal astrocytes. When heterologously expressed in HEK293T or CHO-K1 cells, each TTYH isoform showed a significant I Cl,swell with similar aquaporin-4 dependency, pharmacological properties and glutamate permeability as I Cl,swell observed in native astrocytes. Mutagenesis-based structure-activity analysis revealed that positively charged arginine residue at 165 in TTYH1 and 164 in TTYH2 is critical for the formation of the channel-pore. Our results demonstrate that TTYH family confers the bona fide VRAC swell in the brain.

The lack of cost effective, industrial‐scale production methods hinders the widespread applications of graphene materials. In spite of its applicability in the mass production of graphene flakes, arc discharge has not received considerable attention because of its inability to control the synthesis and heteroatom doping. In this study, a facile approach is proposed for improving doping efficiency in N‐doped graphene synthesis through arc discharge by utilizing anodic carbon fillers. Compared to the N‐doped graphene (1–1.5% N) synthesized via the arc process according to previous literature, the resulting graphene flakes show a remarkably increased doping level (≈3.5% N) with noticeable graphitic N enrichment, which is rarely achieved by the conventional process, while simultaneously retaining high turbostratic crystallinity. The electrolyte ion storage of synthesized materials is examined in which synthesized N‐doped graphene material exhibits a remarkable area normalized capacitance of 63 µF cm−2. The surprisingly high areal capacitance, which is superior to that of most carbon materials, is attributed to the synergistic effect of extrinsic pseudocapacitance, high crystallinity, and abundance of exposed graphene edges. These results highlight the great potentials of N‐doped graphene flakes produced by arc discharge in graphene‐based supercapacitors, along with well‐studied active exfoliated graphene and reduced graphene oxide.

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Fiber-shaped supercapacitors (FSSCs) are the most state-of-the-art power supplies suitable for wearable devices, but the intrinsically limited cylindrical space of fibers restricts their high electrochemical performance, which must be overcome with a delicate and systematic architectural process. Here, a simple but effective 3D architectural strategy for fabricating FSSCs with high performance and flexibility is proposed. Highly conductive liquid crystal spun carbon nanotube fiber (CNTF) is an excellent 1D core fiber for the electrophoretic deposition of graphene oxide (GO). The deposited GO forms a vertical 3D structure on the CNTF (VG@CNTF), which can be successfully preserved by a consecutive coating of pseudocapacitive active materials onto the surface of VG. Notably, a solid-state asymmetric FSSC shows an outstanding performance of 65 Wh kg −1 at 100 kW kg −1 and exceptional stability and flexibility (capacitance retention of 98.60% at bending angles of 90° and 93.1% after 5000 bending cycles). This work can provide new insight into the development of high-performance FSSCs for practical wearable applications.

CNT fibers (CNTFs) are excellent platforms for fiber-shaped supercapacitors, offering both high electric conductivity and mechanical resilience. Here, we propose a polyaniline (PANI)/CNTF composite structure that utilizes a state-of-the-art liquidcrystal (LC)-spun CNTF as the ultimate conductive and flexible electrode. CNTFs assume a highly dense LC phase with a high electrical conductivity of 14 kS cm −1 , which is similar to that of its metal counterpart and suitable as a good current collector. Pseudocapacitive PANI can be homogeneously polymerized directly onto the smooth surface of the CNTFs by using the sonochemical polymerization method. The optimized synthetic process produces PANI in a favorable chemical state with good contact properties at the CNTF interface, exhibiting a high capacitance (738 F g −1 at 1 A g −1 ) even at an extremely fast charge/ discharge rate (604 F g −1 at 100 A g −1 ). Moreover, the superior mechanical resilience of the CNTFs enables excellent flexibility, showing a negligible capacitance decay after 15 000 bending cycles, even with tight knots in the middle. These results highlight the excellent potential of highly densified CNTFs in next-generation flexible supercapacitors for practical wearable applications.

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