Air-Stable and Low-Cost High-Voltage Hydrated Eutectic Electrolyte for High-Performance Aqueous Aluminum-Ion Rechargeable Battery with Wide-Temperature Range.

Aqueous aluminum-ion batteries (AAIBs) are considered as a promising alternative to lithium-ion batteries due to their large theoretical capacity, high safety, and low cost. However, the uneven deposition, hydrogen evolution reaction (HER), and corrosion during cycling impede the development of AAIBs, especially under a harsh environment. Here, a hydrated eutectic electrolyte (AATH40) composed of Al(OTf)3, acetonitrile (AN), triethyl phosphate (TEP), and H2O was designed to improve the electrochemical performance of AAIBs in a wide temperature range. The combination of molecular dynamics simulations and spectroscopy analysis reveals that AATH40 has a less-water-solvated structure [Al(AN)2(TEP)(OTf)2(H2O)]3+, which effectively inhibits side reactions, decreases the freezing point, and extends the electrochemical window of the electrolyte. Furthermore, the formation of a solid electrolyte interface, which effectively inhibits HER and corrosion, has been demonstrated by X-ray photoelectron spectroscopy, X-ray diffraction tests, and in situ differential electrochemical mass spectrometry. Additionally, operando synchrotron Fourier transform infrared spectroscopy and electrochemical quartz crystal microbalance with dissipation monitoring reveal a three-electron storage mechanism for the Al//polyaniline full cells. Consequently, AAIBs with this electrolyte exhibit improved cycling stability within the temperature range of -10-50 °C. This present study introduces a promising methodology for designing electrolytes suitable for low-cost, safe, and stable AAIBs over a wide temperature range.

Advanced cathodes for aqueous Zn batteries beyond Zn2+ intercalation.

Aqueous zinc (Zn) batteries have attracted global attention for energy storage. Despite significant progress in advancing Zn anode materials, there has been little progress in cathodes. The predominant cathodes working with Zn2+/H+ intercalation, however, exhibit drawbacks, including a high Zn2+ diffusion energy barrier, pH fluctuation(s) and limited reproducibility. Beyond Zn2+ intercalation, alternative working principles have been reported that broaden cathode options, including conversion, hybrid, anion insertion and deposition/dissolution. In this review, we report a critical assessment of non-intercalation-type cathode materials in aqueous Zn batteries, and identify strengths and weaknesses of these cathodes in small-scale batteries, together with current strategies to boost material performance. We assess the technical gap(s) in transitioning these cathodes from laboratory-scale research to industrial-scale battery applications. We conclude that S, I2 and Br2 electrodes exhibit practically promising commercial prospects, and future research is directed to optimizing cathodes. Findings will be useful for researchers and manufacturers in advancing cathodes for aqueous Zn batteries beyond Zn2+ intercalation.

Electropolymerized Bipolar Poly(2,3-diaminophenazine) Cathode for High-Performance Aqueous Al-Ion Batteries with An Extended Temperature Range of -20 to 45 °C.

Achieving reversible insertion/extraction in most cathodes for aqueous aluminum ion batteries (AAIBs) is a significant challenge due to the high charge density of Al3+ and strong electrostatic interactions. Organic materials facilitate the hosting of multivalent carriers and rapid ions diffusion through the rearrangement of chemical bonds. Here, a bipolar conjugated poly(2,3-diaminophenazine) (PDAP) on carbon substrates prepared via a straightforward electropolymerization method is introduced as cathode for AAIBs. The integration of n-type and p-type active units endow PDAP with an increased number of sites for ions interaction. The long-range conjugated skeleton enhances electron delocalization and collaborates with carbon to ensure high conductivity. Moreover, the strong intermolecular interactions including π-π interaction and hydrogen bonding significantly enhance its stability. Consequently, the Al//PDAP battery exhibits a large capacity of 338 mAh g-1 with long lifespan and high-rate capability. It consistently demonstrates exceptional electrochemical performances even under extreme conditions with capacities of 155 and 348 mAh g-1 at -20 and 45 °C, respectively. In/ex situ spectroscopy comprehensively elucidates its cation/anion (Al3+ /H3 O+ and ClO4 - ) storage with 3-electron transfer in dual electroactive centers (C═N and -NH-). This study presents a promising strategy for constructing high-performance organic cathode for AAIBs over a wide temperature range.

Wiskott-Aldrich syndrome: A new synonym mutation in the WAS gene.

Wiskott-Aldrich syndrome (WAS) is a rare X-linked recessive primary immunodeficiency disorder. Mutations in the WAS gene are considered to be the primary cause of WAS. In this work, we report a boy who presented with intracranial hemorrhage (ICH) as an initial symptom and detects a novel pathogenic synonymous mutation in his WAS gene. His mother was a carrier of the mutant gene. The mutation, located at position c.273 (c.273 G>A) in exon 2, is a synonym mutation and predicted to affect protein expression by disrupting gene splicing. This study summarizes the diagnosis and treatment process of the patient and expands the genetic spectrum of WAS.

Alkaline-based aqueous sodium-ion batteries for large-scale energy storage.

Aqueous sodium-ion batteries are practically promising for large-scale energy storage, however energy density and lifespan are limited by water decomposition. Current methods to boost water stability include, expensive fluorine-containing salts to create a solid electrolyte interface and addition of potentially-flammable co-solvents to the electrolyte to reduce water activity. However, these methods significantly increase costs and safety risks. Shifting electrolytes from near neutrality to alkalinity can suppress hydrogen evolution while also initiating oxygen evolution and cathode dissolution. Here, we present an alkaline-type aqueous sodium-ion batteries with Mn-based Prussian blue analogue cathode that exhibits a lifespan of 13,000 cycles at 10 C and high energy density of 88.9 Wh kg-1 at 0.5 C. This is achieved by building a nickel/carbon layer to induce a H3O+-rich local environment near the cathode surface, thereby suppressing oxygen evolution. Concurrently Ni atoms are in-situ embedded into the cathode to boost the durability of batteries.

Hydrated Eutectic Electrolyte Induced Bilayer Interphase for High-Performance Aqueous Zn-Ion Batteries with 100 °C Wide-Temperature Range.

The practical implementation of aqueous zinc-ion batteries (AZIBs) encounters challenges such as dendrite growth, parasitic reactions, and severe decay in battery performance under harsh environments. Here, a novel hydrated eutectic electrolyte (HEE) composed of Zn(ClO4 )2 ·6H2 O, ethylene glycol (EG), and InCl3 solution is introduced to effectively extend the lifespan of AZIBs over a wide temperature range from -50 to 50 °C. Molecular dynamics simulations and spectroscopy analysis demonstrate that the H2 O molecules are confined within the liquid eutectic network through dual-interaction, involving coordination with Zn2+ and hydrogen bonding with EG, thus weakening the activity of free water and extending the electrochemical window. Importantly, cryo-transmission electron microscopy and spectroscopy techniques reveal that HEE in situ forms a zincophobic/zincophilic bilayer interphase by the dissociation-reduction of eutectic molecules. Specifically, the zincophilic interphase reduces the energy barrier for Zn nucleation, promoting uniform Zn deposition, while the zincophobic interphase prevents active water from contacting the Zn surface, thus inhibiting the side reactions. Furthermore, the relationships between the structural evolution of the liquid eutectic network and interfacial chemistry at electrode/electrolyte interphase are further discussed in this work. The scalability of this design strategy can bring benefits to AZIBs operating over a wide temperature range.

High-Reversibility Sulfur Anode for Advanced Aqueous Battery.

Despite being extensively explored as cathodes in batteries, sulfur (S) can function as a low-potential anode by changing charge carriers in electrolytes. Here, a highly reversible S anode that fully converts from S8 0 to S2- in static aqueous S-I2 batteries by using Na+ as the charge carrier is reported. This S anode exhibits a low potential of -0.5 V (vs standard hydrogen electrode) and a near-to-theoretical capacity of 1404 mA h g-1 . Importantly, it shows significant advantages over the widely used Zn anode in aqueous media by obviating dendrite formation and H2 evolution. To suppress "shuttle effects" faced by both S and I2 electrodes, a scalable sulfonated polysulfone (SPSF) membrane is proposed, which is superior to commercial Nafion in cost (US$1.82 m-2  vs $3500 m-2 ) and environmental benignity. Because of its ultra-high selectivity in blocking polysulfides/iodides, the battery with SPSF displays excellent cycling stability. Even under 100% depth of discharge, the battery demonstrates high capacity retention of 87.6% over 500 cycles, outperforming Zn-I2 batteries with 3.1% capacity under the same conditions. These findings broaden anode options beyond metals for high-energy, low-cost, and fast-chargeable batteries.

A biocompatible electrolyte enables highly reversible Zn anode for zinc ion battery.

Progress towards the integration of technology into living organisms requires power devices that are biocompatible and mechanically flexible. Aqueous zinc ion batteries that use hydrogel biomaterials as electrolytes have emerged as a potential solution that operates within biological constraints; however, most of these batteries feature inferior electrochemical properties. Here, we propose a biocompatible hydrogel electrolyte by utilising hyaluronic acid, which contains ample hydrophilic functional groups. The gel-based electrolyte offers excellent anti-corrosion ability for zinc anodes and regulates zinc nucleation/growth. Also, the gel electrolyte provides high battery performance, including a 99.71% Coulombic efficiency, over 5500 hours of long-term stability, improved cycle life of 250 hours under a high zinc utilization rate of 80%, and high biocompatibility. Importantly, the Zn//LiMn2O4 pouch cell exhibits 82% capacity retention after 1000 cycles at 3 C. This work presents a promising gel chemistry that controls zinc behaviour, offering great potential in biocompatible energy-related applications and beyond.

Low-cost and Non-flammable Eutectic Electrolytes for Advanced Zn-I2 Batteries.

As a burgeoning electrolyte system, eutectic electrolytes based on ZnCl2 /Zn(CF3 SO3 )2 /Zn(TFSI)2 have been widely proposed in advanced Zn-I2 batteries; however, safety and cost concerns significantly limit their applications. Here, we report new-type ZnSO4 -based eutectic electrolytes that are both safe and cost-effective. Their universality is evident in various solvents of polyhydric alcohols, in which multiple -OH groups not only involve in Zn2+ solvation but also interact with water, resulting in the high stability of electrolytes. Taking propylene glycol-based hydrated eutectic electrolyte as an example, it features significant advantages in non-flammability and low price that is <1/200 cost of Zn(CF3 SO3 )2 /Zn(TFSI)2 -based eutectic electrolytes. Moreover, its effectiveness in confining the shuttle effects of I2 cathode and side reactions of Zn anodes is evidenced, resulting in Zn-I2 cells with high reversibility at 1 C and 91.4 % capacity remaining under 20 C. After scaling up to the pouch cell with a record mass loading of 33.3 mg cm-2 , super-high-capacity retention of 96.7 % is achieved after 500 cycles, which exceeds other aqueous counterparts. This work significantly broadens the eutectic electrolyte family for advanced Zn battery design.

Suppressing Hydrogen Evolution via Anticatalytic Interfaces toward Highly Efficient Aqueous Zn-Ion Batteries.

Aqueous Zn-ion batteries hold practical promise for large-scale energy storage because of the safety and affordability of aqueous-based electrolytes; in addition, the manufacturing process is significantly simplified by direct employment of Zn metal as an anode. However, hydrogen evolution due to near-surface water dissociation has hindered large-scale applications of them. Here, we report the suppression of the hydrogen evolution reaction via a CuN3-coordinated graphitic carbonitride (CuN3-C3N4) anticatalytic interface to achieve highly efficient aqueous Zn-ion batteries. Based on in situ gas chromatography and in situ synchrotron-based X-ray diffraction spectroscopy, we demonstrated that the hydrogen evolution reaction triggers the Zn4SO4(OH)6·xH2O formation. A combination of in situ infrared spectroscopy and density functional theory simulations has proved to stabilize near-surface H3O+ species and regulate adsorption of H* intermediates by an anticatalytic interface for hydrogen evolution reaction suppression. Consequently, the anticatalytic interface greatly improves the Coulombic efficiency of Zn plating/stripping to ∼99.7% for 5500 cycles and the cycling reversibility to over 1300 h at 1 mA cm-2 and 1 mAh cm-2. With an anticatalytic interface, the full cell shows an excellent Coulombic efficiency of 98.3% over 400 cycles at 1C. These findings provide strategic insight for targeted designing of highly efficient aqueous Zn-ion batteries.

pH-Triggered Molecular Switch Toward Texture-Regulated Zn Anode.

Zn electrodes in aqueous media exhibit an unstable Zn/electrolyte interface due to severe parasitic reactions and dendrite formation. Here, a dynamic Zn interface modulation based on the molecular switch strategy is reported by hiring γ-butyrolactone (GBL) in ZnCl2 /H2 O electrolyte. During Zn plating, the increased interfacial alkalinity triggers molecular switch from GBL to γ-hydroxybutyrate (GHB). GHB strongly anchors on Zn surface via triple Zn-O bonding, leading to suppressive hydrogen evolution and texture-regulated Zn morphology. Upon Zn stripping, the fluctuant pH turns the molecular switch reaction off through the cyclization of GHB to GBL. This dynamic molecular switch strategy enables high Zn reversibility with Coulombic efficiency of 99.8 % and Zn||iodine batteries with high-cyclability under high Zn depth of discharge (50 %). This study demonstrates the importance of dynamic modulation for Zn electrode and realizes the reversible molecular switch strategy to enhance its reversibility.

Triple-Function Electrolyte Regulation toward Advanced Aqueous Zn-Ion Batteries.

The poor Zn reversibility has been criticized for limiting applications of aqueous Zn-ion batteries (ZIBs); however, its behavior in aqueous media is not fully uncovered yet. Here, this knowledge gap is addressed, indicating that Zn electrodes face a O2 -involving corrosion, besides H2 evolution and dendrite growth. Differing from aqueous Li/Na batteries, removing O2 cannot enhance ZIB performance because of the aggravated competing H2 evolution. To address Zn issues, a one-off electrolyte strategy is reported by introducing the triple-function C3 H7 Na2 O6 P, which can take effects during the shelf time of battery. It regulates H+ concentration and reduces free-water activity, inhibiting H2 evolution. A self-healing solid/electrolyte interphase (SEI) can be triggered before battery operation, which suppresses O2 adsorption corrosion and dendritic deposition. Consequently, a high Zn reversibility of 99.6% is achieved under a high discharge depth of 85%. The pouch full-cell with a lean electrolyte displays a record lifespan with capacity retention of 95.5% after 500 cycles. This study not only looks deeply into Zn behavior in aqueous media but also underscores rules for the design of active metal anodes, including Zn and Li metals, during shelf time toward real applications.

Understanding H2 Evolution Electrochemistry to Minimize Solvated Water Impact on Zinc-Anode Performance.

H2 evolution is the reason for poor reversibility and limited cycle stability with Zn-metal anodes, and impedes practical application in aqueous zinc-ion batteries (AZIBs). Here, using a combined gas chromatography experiment and computation, it is demonstrated that H2 evolution primarily originates from solvated water, rather than free water without interaction with Zn2+ . Using linear sweep voltammetry (LSV) in salt electrolytes, H2 evolution is evidenced to occur at a more negative potential than zinc reduction because of the high overpotential against H2 evolution on Zn metal. The hypothesis is tested and, using a glycine additive to reduce solvated water, it is confirmed that H2 evolution and "parasitic" side reactions are suppressed on the Zn anode. This electrolyte additive is evidenced to suppress H2 evolution, reduce corrosion, and give a uniform Zn deposition in Zn|Zn and Zn|Cu cells. It is demonstrated that Zn|PANI (highly conductive polyaniline) full cells exhibit boosted electrochemical performance in 1 M ZnSO4 -3 M glycine electrolyte. It is concluded that this new understanding of electrochemistry of H2 evolution can be used for design of relatively low-cost and safe AZIBs for practical large-scale energy storage.

Polyiodide Confinement by Starch Enables Shuttle-Free Zn-Iodine Batteries.

Aqueous Zn-iodine (Zn-I2 ) batteries have been regarded as a promising energy-storage system owing to their high energy/power density, safety, and cost-effectiveness. However, the polyiodide shuttling results in serious active mass loss and Zn corrosion, which limits the cycling life of Zn-I2 batteries. Inspired by the chromogenic reaction between starch and iodine, a structure confinement strategy is proposed to suppress polyiodide shuttling in Zn-I2 batteries by hiring starch, due to its unique double-helix structure. In situ Raman spectroscopy demonstrates an I5 - -dominated I- /I2 conversion mechanism when using starch. The I5 - presents a much stronger bonding with starch than I3 - , inhibiting the polyiodide shuttling in Zn-I2 batteries, which is confirmed by in situ ultraviolet-visible spectra. Consequently, a highly reversible Zn-I2 battery with high Coulombic efficiency (≈100% at 0.2 A g-1 ) and ultralong cycling stability (>50 000 cycles) is realized. Simultaneously, the Zn corrosion triggered by polyiodide is effectively inhibited owing to the desirable shuttling-suppression by the starch, as evidenced by X-ray photoelectron spectroscopy analysis. This work provides a new understanding of the failure mechanism of Zn-I2 batteries and proposes a cheap but effective strategy to realize high-cyclability Zn-I2 batteries.

Harnessing Plasma-Assisted Doping Engineering to Stabilize Metallic Phase MoSe2 for Fast and Durable Sodium-Ion Storage.

Metallic-phase selenide molybdenum (1T-MoSe2 ) has become a rising star for sodium storage in comparison with its semiconductor phase (2H-MoSe2 ) owing to the intrinsic metallic electronic conductivity and unimpeded Na+ diffusion structure. However, the thermodynamically unstable nature of 1T phase renders it an unprecedented challenge to realize its phase control and stabilization. Herein, a plasma-assisted P-doping-triggered phase-transition engineering is proposed to synthesize stabilized P-doped 1T phase MoSe2 nanoflower composites (P-1T-MoSe2 NFs). Mechanism analysis reveals significantly decreased phase-transition energy barriers of the plasma-induced Se-vacancy-rich MoSe2 from 2H to 1T owing to its low crystallinity and reduced structure stability. The vacancy-rich structure promotes highly concentrated P doping, which manipulates the electronic structure of the MoSe2 and urges its phase transition, acquiring a high transition efficiency of 91% accompanied with ultrahigh phase stability. As a result, the P-1T-MoSe2 NFs deliver an exceptional high reversible capacity of 510.8 mAh g-1 at 50 mA g-1 with no capacity fading over 1000 cycles at 5000 mA g-1 for sodium storage. The underlying mechanism of this phase-transition engineering verified by profound analysis provides informative guide for designing advanced materials for next-generation energy-storage systems.

Catalytic Oxidation of K2S via Atomic Co and Pyridinic N Synergy in Potassium-Sulfur Batteries.

Potassium-sulfur batteries hold practical promise for next-generation batteries because of their high theoretical gravimetric energy density and low cost. However, significant impediments are the sluggish K2S oxidation kinetics and a lack of atomic-level understanding of K2S oxidation. Here, for the first time, we report the catalytic oxidation of K2S on a sulfur host with Co single atoms immobilized on nitrogen-doped carbon. On the basis of combined spectroscopic characterizations, electrochemical evaluation, and theoretical computations, we show a synergistic effect of dynamic Co-S and N-K interactions to catalyze K2S oxidation. The resultant potassium-sulfur battery exhibited high capacities of 773 and 535 mAh g-1 under high current densities of 1 and 2 C, respectively. These findings provide atomic-scale insights for the rational design of highly efficient sulfur hosts.

Studying the Conversion Mechanism to Broaden Cathode Options in Aqueous Zinc-Ion Batteries.

Aqueous Zn-ion batteries (ZIBs) are regarded as alternatives to Li-ion batteries benefiting from both improved safety and environmental impact. The widespread application of ZIBs, however, is compromised by the lack of high-performance cathodes. Currently, only the intercalation mechanism is widely reported in aqueous ZIBs, which significantly limits cathode options. Beyond Zn-ion intercalation, we comprehensively study the conversion mechanism for Zn2+ storage and its diffusion pathway in a CuI cathode, indicating that CuI occurs a direct conversion reaction without Zn2+ intercalation due to the high energy barrier for Zn2+ intercalation and migration. Importantly, this direct conversion reaction mechanism can be readily generalized to other high-capacity cathodes, such as Cu2 S (336.7 mA h g-1 ) and Cu2 O (374.5 mA h g-1 ), indicating its practical universality. Our work enriches the Zn-ion storage mechanism and significantly broadens the cathode horizons towards next-generation ZIBs.

Crystallographic-Site-Specific Structural Engineering Enables Extraordinary Electrochemical Performance of High-Voltage LiNi0.5 Mn1.5 O4 Spinel Cathodes for Lithium-Ion Batteries.

The development of reliable and safe high-energy-density lithium-ion batteries is hindered by the structural instability of cathode materials during cycling, arising as a result of detrimental phase transformations occurring at high operating voltages alongside the loss of active materials induced by transition metal dissolution. Originating from the fundamental structure/function relation of battery materials, the authors purposefully perform crystallographic-site-specific structural engineering on electrode material structure, using the high-voltage LiNi0.5 Mn1.5 O4 (LNMO) cathode as a representative, which directly addresses the root source of structural instability of the Fd 3 ¯ m structure. By employing Sb as a dopant to modify the specific issue-involved 16c and 16d sites simultaneously, the authors successfully transform the detrimental two-phase reaction occurring at high-voltage into a preferential solid-solution reaction and significantly suppress the loss of Mn from the LNMO structure. The modified LNMO material delivers an impressive 99% of its theoretical specific capacity at 1 C, and maintains 87.6% and 72.4% of initial capacity after 1500 and 3000 cycles, respectively. The issue-tracing site-specific structural tailoring demonstrated for this material will facilitate the rapid development of high-energy-density materials for lithium-ion batteries.

Selective Interface Synthesis of Cobalt Metaphosphate Nanosheet Arrays Motivated by Functionalized Carbon Cloths for Fast and Durable Na/K-Ion Storage.

Exploiting novel nanomaterials with fast and durable sodium/potassium ion storage capability is key to alleviate the application limitations of lithium-ion batteries. Herein, a novel energy storage material based on cobalt metaphosphate nanosheet arrays self-supported on carbon cloths [Co(PO3)2 NSs/CC] is fabricated by a two-step strategy. This rationally designed strategy avoids the preparation of the complex {Co[O2P(OtBu)2]2}n precursor, which significantly simplifies the synthesis process. The active CC acts not only as an electrically conductive substrate as usual but also as a functional basis to suppress PH3-involved reaction and to promote HPO3-involved reaction during the phosphating process, contributing to the formation of Co(PO3)2. The mutual cross-linked porous Co(PO3)2 nanosheets vertically grow on the surface of activated CC, ensuring sufficient electrolyte infiltration and fast electron transport among the electrodes. Sodium ion storage analysis for the Co(PO3)2 NSs/CC electrode reveals a multi-step reaction mechanism with high reversibility, as reflected by the high reversible capacity (667 mA h g-1 at 50 mA g-1) and excellent cyclability (with almost no capacity decay over 500 cycles). This novel electrode is also well capable of storing potassium ions, exhibiting high reversible capacity, which outperforms most reported anodes for potassium-ion batteries. The development of this novel high-performance nanomaterial would advance the performance of sodium/potassium-ion batteries toward practical applications.

Electrolyte Design for In Situ Construction of Highly Zn2+ -Conductive Solid Electrolyte Interphase to Enable High-Performance Aqueous Zn-Ion Batteries under Practical Conditions.

Rechargeable aqueous Zn-ion batteries promise high capacity, low cost, high safety, and sustainability for large-scale energy storage. The Zn metal anode, however, suffers from the dendrite growth and side reactions that are mainly due to the absence of an appropriate solid electrolyte interphase (SEI) layer. Herein, the in situ formation of a dense, stable, and highly Zn2+ -conductive SEI layer (hopeite) in aqueous Zn chemistry is demonstrated, by introducing Zn(H2 PO4 )2 salt into the electrolyte. The hopeite SEI (≈140 nm thickness) enables uniform and rapid Zn-ion transport kinetics for dendrite-free Zn deposition, and restrains the side reactions via isolating active Zn from the bulk electrolyte. Under practical testing conditions with an ultrathin Zn anode (10 µm), a low negative/positive capacity ratio (≈2.3), and a lean electrolyte (9 µL mAh-1 ), the Zn/V2 O5 full cell retains 94.4% of its original capacity after 500 cycles. This work provides a simple yet practical solution to high-performance aqueous battery technology via building in situ SEI layers.