A long-life, high-capacity, highly safe and wearable solid-state zinc ion battery was constructed using a novel gelatin and PAM based electrolyte.

Emerging research toward next-generation flexible and wearable electronics has stimulated the efforts to build highly wearable, durable, and deformable energy devices with excellent electrochemical performances. Here, we develop a high-performance, waterproof, tailorable, and stretchable yarn zinc ion battery (ZIB) using double-helix yarn electrodes and a cross-linked polyacrylamide (PAM) electrolyte. Due to the high ionic conductivity of the PAM electrolyte and helix structured electrodes, the yarn ZIB delivers a high specific capacity and volumetric energy density (302.1 mAh g and 53.8 mWh cm, respectively) as well as excellent cycling stability (98.5% capacity retention after 500 cycles). More importantly, the quasi-solid-state yarn ZIB also demonstrates superior knittability, good stretchability (up to 300% strain), and superior waterproof capability (high capacity retention of 96.5% after 12 h underwater operation). In addition, the long yarn ZIB can be tailored into short ones, and each part still functions well. Owing to its weavable and tailorable nature, a 1.1 m long yarn ZIB was cut into eight parts and woven into a textile that was used to power a long flexible belt embedded with 100 LEDs and a 100 cm flexible electroluminescent panel.

Stretchability and compressibility of supercapacitors is an essential element of modern electronics, such as flexible, wearable devices. Widely used polyvinyl alcohol-based electrolytes are neither very stretchable nor compressible, which fundamentally limits the realization of supercapacitors with high stretchability and compressibility. A new electrolyte that is intrinsically super-stretchable and compressible is presented. Vinyl hybrid silica nanoparticle cross-linkers were introduced into polyacrylamide hydrogel backbones to promote dynamic cross-linking of the polymer networks. These cross-linkers serve as stress buffers to dissipate energy when strain is applied, providing a solution to the intrinsically low stretchability and compressibility shortcomings of conventional supercapacitors. The newly developed supercapacitor and electrolyte can be stretched up to an unprecedented 1000 % strain with enhanced performance, and compressed to 50 % strain with good retention of the initial performance.

With intrinsic safety and much higher energy densities than supercapacitors, rechargeable nickel/cobalt-zinc-based textile batteries are promising power sources for next generation personalized wearable electronics. However, high-performance wearable nickel/cobalt-zinc-based batteries are rarely reported because there is a lack of industrially weavable and knittable highly conductive yarns. Here, we use scalably produced highly conductive yarns uniformly covered with zinc (as anode) and nickel cobalt hydroxide nanosheets (as cathode) to fabricate rechargeable yarn batteries. They possess a battery level capacity and energy density, as well as a supercapacitor level power density. They deliver high specific capacity of 5 mAh cm and energy densities of 0.12 mWh cm and 8 mWh cm (based on the whole solid battery). They exhibit ultrahigh rate capabilities of 232 C (liquid electrolyte) and 116 C (solid electrolyte), which endows the batteries excellent power densities of 32.8 mW cm and 2.2 W cm (based on the whole solid battery). These are among the highest values reported so far. A wrist band battery is further constructed by using a large conductive cloth woven from the conductive yarns by a commercial weaving machine. It powers various electronic devices successfully, enabling dual functions of wearability and energy storage.

No abstract

Sec1/Munc18-family (SM) proteins are required for SNARE-mediated membrane fusion, but their mechanism(s) of action remain controversial. Using single-molecule force spectroscopy, we found that the SM protein Munc18-1 catalyzes step-wise zippering of three synaptic SNAREs (syntaxin, VAMP2, and SNAP-25) into a four-helix bundle. Catalysis requires formation of an intermediate template complex in which Munc18-1 juxtaposes the N-terminal regions of the SNARE motifs of syntaxin and VAMP2, while keeping their C-terminal regions separated. SNAP-25 binds the templated SNAREs to induce full SNARE zippering. Munc18-1 mutations modulate the stability of the template complex in a manner consistent with their effects on membrane fusion, indicating that chaperoned SNARE assembly is essential for exocytosis. Two other SM proteins, Munc18-3 and Vps33, similarly chaperone SNARE assembly via a template complex, suggesting that SM protein mechanism is conserved.

the realization of fully flexible and wear able electronics, appropriate flexible and wearable power supply devices with small volume, light weight, and good electro chemical performances, such as flexible supercapacitors and batteries, are highly demanded. [1][2][3][4][5][6] In particular, high safety, accompanied with good mechanical dura bility in terms of stretching or twisting reliability, compression stability, and high energy density is the key component for designing and fabricating wearable energy storage devices. [7][8][9][10][11][12][13][14][15] Supercapacitors, also named ultracapac itors or electrochemical capacitors, store energy through ion adsorption or redox reaction which can be safely and quickly charged/discharged and easily packaged by sandwiching an active layer between two electrodes. [7,8,16,17] Due to their high power density of up to 10 kW kg −1 , small volume, long cycling ability of ≈10 000 times, and environmental friendliness, supercapacitors are regarded as one of the most promising energy storage devices. [7,8,18] However, con ventional supercapacitors are stiff and cumbersome which are extremely difficult to perform as flexible energy supply.To date, a research frontier in energy storage has focused on developing flexible supercapacitors with promising electro chemical and mechanical performances. [2,7,19,20] With regard to flexible supercapacitors, their superior electrochemical per formances, i.e., high power density, superior stability and high safety, and the integration of flexibility in supercapacitors, are of great importance for powering various flexible electro nics and enabling applications in multifunctional flexible electronics. [21,22] Also, substantial efforts have been made to improve the electro chemical and mechanical performances of flexible supercapacitors. [1,10,16,[22][23][24][25][26] In this regard, flexible and wearable supercapacitors hold great promise as new energy storage devices for wearable electronics. The increasing expan sion of practical applications has boosted the development of supercapacitors, including yarn/fiber shaped and planar ones, which exhibit excellent electrochemical performances. [1,10,16,[22][23][24][25][26] Herein, we provide a comprehensive view of the recent progress and advances made in flexible and wearable superca pacitors by categorizing different flexible electrodes. Through a material based classification, the electrode materials based on carbon materials, metal based materials, and conductive Recently, wearable electronic devices including electrical sensors, flexible displays, and health monitors have received considerable attention and experienced rapid progress. Wearable supercapacitors attract tremendous attention mainly due to their high stability, low cost, fast charging/discharging, and high efficiency; properties that render them value for developing fully flexible devices. In this Concept, the recent achievements and advances made in flexible and wearable supercapacitors are presented, especially highlighting the...

Many antimicrobial peptides (AMPs) selectively target and form pores in microbial membranes. However, the mechanisms of membrane targeting, pore formation and function remain elusive. Here we report an experimentally guided unbiased simulation methodology that yields the mechanism of spontaneous pore assembly for the AMP maculatin at atomic resolution. Rather than a single pore, maculatin forms an ensemble of structurally diverse temporarily functional low-oligomeric pores, which mimic integral membrane protein channels in structure. These pores continuously form and dissociate in the membrane. Membrane permeabilization is dominated by hexa-, hepta- and octamers, which conduct water, ions and small dyes. Pores form by consecutive addition of individual helices to a transmembrane helix or helix bundle, in contrast to current poration models. The diversity of the pore architectures—formed by a single sequence—may be a key feature in preventing bacterial resistance and could explain why sequence–function relationships in AMPs remain elusive.