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This article, titled "Guest Editorial for the Special Issue on Aqueous Electrolyte Batteries," discusses the advancements in aqueous energy storage systems over the past decade. Aqueous energy storage is seen as a viable alternative to lithium-ion batteries, particularly for large-scale energy storage due to its high safety and low cost. However, there are still challenges to overcome, such as side reactions caused by aqueous environment electrolytes and the stability of electrode materials in an aqueous environment. The article also highlights a special issue that focuses on various topics related to aqueous energy storage, including proton-based battery chemistry, aqueous aluminum metal batteries, aqueous lithium-ion batteries, aqueous zinc ion batteries, smart aqueous batteries, and energy storage and conversion in electric eels biomimetics. The authors express gratitude to all contributors for their efforts in promoting the development of aqueous energy storage. [Extracted from the article]

We report a hard X-ray photoelectron spectroscopy (HX-PES) investigation on valence band structure of Boron Nitrides (BN) having different morphologies, including nanosheets, nanotubes, and micro-sized particles. Very weak morphology/valence band structure dependence was observed. For each case, the B-N π-band overlapping with σ-band between 0 to -12.5 eV and the s-band below -15 eV were identified. No obvious morphology-induced band shifts and intensity variations were observed. First-principles calculations based on density functional theory were performed and the results were compared with the experimental data. This theoretical analysis well explains the weak morphology dependent valence band spectra of BN nanomaterials obtained during HX-PES measurements. [ABSTRACT FROM AUTHOR]

The preparation of high specific-capacity pseudocapacitive transition-metal-oxide/hydroxide (TMH) materials into transparent micro-structure electrodes is a great challenge and has become the bottleneck restricting the performance of transparent flexible supercapacitors. Beyond that, extending the operating voltage window is an urgent need for improving energy density. Here, Co(OH) 2 nanosheets and amorphous FeOOH nanowires were prepared into transparent films through a simple and scalable bio-inspired method at the air-solution interface. Both nanostructures are enwrapped in graphene shells (Co@Gr-TFandFe@Gr-TF) for use as transparent asymmetric pseudocapacitive electrodes. The unique encapsulation structures (1) provide pseudocapacitive electrode materials, especially an amorphous FeOOH structure cathode, (2) build up rapid three-dimensional electron and ion transport pathways together with the underlying ITO layer, (3) alleviate the exfoliation and dissolution of the active materials into electrolyte, and (4) extend the potential window of the FeOOH cathode from −0.8 ∼ 0 V to −1.2 ∼ 0 V with minimal cycling stability degradation. The asymmetric transparent and flexible supercapacitor based on Co@Gr-TF//Fe@Gr-TF operated at 1.8 V exhibits good transparency (50.5% at 550 nm), high specific capacitance (25.5 mF cm −2 , one order higher than the maximum value reported for FFT-GP), and high energy density (1.04 mWh cm −3 , comparable to that of nontransparent devices) as well as a long cycle life (10 000 cycles) with high-capacity retention (83.5%). [ABSTRACT FROM AUTHOR]

Dielectric polymer composites with high thermal conductivity are very promising for microelectronic packaging and thermal management application in new energy systems such as solar cells and light emitting diodes (LEDs). However, a well-known paradox is that conventional composites with high thermal conductivity usually suffer from the high dielectric constant and high dielectric loss, while on the other hand, composite materials with excellent dielectric properties usually possess low thermal conductivity. In this work, an ideal dielectric thermally conductive epoxy nanocomposite is successfully fabricated using polyhedral oligosilsesquioxane (POSS) functionalized boron nitride nanotubes (BNNTs) as fillers. The nanocomposites with 30 wt% fraction of POSS modified BNNTs exhibit much lower dielectric constant, dielectric loss tangent, and coefficient of thermal expansion in comparison with the pure epoxy resin. As an example, below 100 Hz, the dielectric loss of the nanocomposites with 20 and 30 wt% BNNTs is reduced by one order of magnitude in comparison with the pure epoxy resin. Moreover, the nanocomposites show a dramatic thermal conductivity enhancement of 1360% in comparison with the pristine epoxy resin at a BNNT loading fraction of 30 wt%. The merits of the designed composites are suggested to originate from the excellent intrinsic properties of embedded BNNTs, effective surface modification by POSS molecules, and carefully developed composite preparation methods. [ABSTRACT FROM AUTHOR]

In this review, a concise research history of low-dimensional boron nitride (BN) nanomaterials followed by recent developments in their synthesis, morphology, properties, and applications are presented. Seventeen years after the initial synthesis of BN nanotubes, research on BN nanomaterials has developed far enough to establish them as one of the most promising inorganic nanosystems. In this regard, it is envisaged that the unique properties of low-dimensional BN systems, such as superb mechanical stiffness, high thermal conductivity, wide optical bandgap, strong ultraviolet emission, thermal stability and chemical inertness will play a key role in prospective developments. [Copyright &y& Elsevier]

Abstract: Multiwalled boron nitride nanotubes (BNNTs) functionalized with Fe3O4 nanoparticles (NPs) were used for arsenic removal from water solutions. Sonication followed by a heating process was developed to in situ functionalize Fe3O4 NPs onto a tube surface. A batch of adsorption experiments conducted at neutral pH (6.9) and room temperature (25°C) and using the developed nanocomposites revealed effective arsenic (V) removal. The Langmuir, Freundlich, and Dubinin-Radushkevich adsorption isotherms were measured for a range of As(V) initial concentrations from 1 to 40mg/L under the same conditions. The equilibrium data well fitted all isotherms, indicating that the mechanism for As(V) adsorption was a combination of chemical complexation and physical electrostatic attraction with a slight preference for chemisorption. The magnetite NPs functionalized on BNNTs led to a simple and rapid separation of magnetic metal-loaded adsorbents from the treated water under an external magnetic field. [Copyright &y& Elsevier]

Abstract: We report on the basic physical quantities of boron nitride nanotubes (BNNTs), namely specific heat capacity and density, which have not been measured to date. A series of differential scanning calorimetry experiments were performed, and specific heat capacity was calculated for multi-walled BNNTs synthesized by chemical vapor deposition using boron and metal oxide as precursor. Very close specific heat capacity values were revealed for BNNTs and a BN powder of hexagonal (-BN) phase. Densities of BNNTs were measured through density analyses of their epoxy composites. Our work is important as far as bulk properties of large amounts of BNNTs are crucial, for example, thermal property and density prediction for composite materials with BNNTs embedded. [Copyright &y& Elsevier]

Abstract: This article presents an overview of the up-to-date developments in boron nitride nanotubes (BNNTs), including theory, fabrication, structure, physical properties, chemical functionalization and applications. Soon after the discovery of carbon nanotubes, BNNTs were theoretically predicted, followed by their successful fabrication by arc-discharge in 1995. Subsequently, various methods were developed for the BNNT synthesis, although till now, the growth of highly pure single-walled BNNTs at large quantities remains a challenge. The physical property investigations reveal that BNNTs’ exhibit a stable wide band gap, superb mechanical strength, high thermal conductivity, ultra-violet light emission, etc. All these properties build up the solid basis for their future technological applications. Chemical modification is also a decent approach to adjust the BNNTs properties. In recent years the yield of multi-walled BNNTs has reached the grams level, that can allow their detailed chemical functionalization studies. So far, many kinds of functionalizations through different weak interactions and covalent bonding were developed. These treatments improved BNNT dispersions in solvents and extended their fields of applications. Moreover, some application-related studies on multi-walled BNNTs, such as composites fabrication, hydrogen storage, biocompatibility, and mechanical, and electrical breakdown tests have also been started in recent years. [ABSTRACT FROM AUTHOR]

We report the fabrication of and investigations into the dielectric and thermal properties of epoxy/boron nitride nanotube (BNNT) composites. It was found that BNNT fillers can effectively adjust the dielectric constant of epoxy. Moreover, the thermal conductivity of epoxy was improved by up to 69 % with 5 wt % BNNTs. Our studies indicate that BNNTs are promising nanofillers for polymers, to obtain and control an adjustable dielectric property and improved thermal conductivity. [ABSTRACT FROM AUTHOR]

Abstract: Large quantities of highly pure BN nanotubes have been synthesized within a wide temperature range through using a mixture of FeO, MgO and boron powder as the precursor. X-ray diffraction pattern indicated highly pure h-BN phase of our sample. The morphology and microstructure were investigated by scanning electron microscopy and transmission electron microscopy. The growth mechanism of BN nanotubes has been clarified to be a catalytic growth. [Copyright &y& Elsevier]

[Display omitted] Due to their superior safety and stability, solid-state electrolytes (SSEs) are a promising alternative to flammable liquid electrolytes in lithium-ion batteries. However, the poor solid–solid contact at the SSEs/electrodes interface remains a significant challenge. To address this issue, inspired by spider silk, we develop a composite polymer electrolyte (SPLZO), which is highly adhesive due to the designed rich hydrogel bond network, containing a supramolecular poly (urethane-urea) (SPU), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and Li 6.5 La 3 Zr 1.5 Ta 0.5 O 12. The abundant hydrogen bonds mainly enabled inherently strong adhesion to ensure intimate electrolyte–electrode contact with low interfacial impedance. Besides, the soft polymer segments facilitate Li+ transport, and the hard components enhance the LiTFSI dissociation and accelerate Li+ motion, resulting in a high ionic conductivity of 1.67 × 10−4 S cm−1. The significantly improved interface contact and high ionic conductivity lead to a decent capacity and cycling performance of the fabricated solid-state lithium-ion batteries. Moreover, the designed SPLZO electrolyte exhibits remarkable deformability, and the flexible lithium-ion battery demonstrates outstanding mechanical flexibility and stability with negligible capacity loss when subjected to various dynamic deformations. This adhesive SSE design strategy opens new possibilities for promoting interfaces in solid-state batteries. [ABSTRACT FROM AUTHOR]

Achieving reversible plating/stripping of zinc (Zn) anodes is crucial in aqueous Zn‐ion batteries (AZIBs). However, undesired dendrite growth and parasitic side reactions severely deteriorate battery lifespan. The construction of stable protective coating is an effective strategy to enhance anode stability. In this study, a multifunctional nanodiamond (ND) inorganic layer is designed and constructed on both Zn and Cu electrodes that can both effectively inhibit dendrite growth and suppress Zn anode corrosion. Experimental results and theoretical calculations demonstrate that this artificial protective layer, with ultra‐high surface energy, enables the controlled creation of abundant nucleation sites (in the order of 1012 cm−2) for the homogenization of ion flux and electric field on the anode. It is found that zinc ions preferentially adhere to the diamond surfaces with lower diffusion barriers, leading to uniform zinc deposition. A symmetric cell with the ND‐protected Zn (Zn‐ND) anode exhibits reversible plating/stripping behavior for an impressive duration of over 3600 h at 1 mA cm−2. Furthermore, the MnO2||Zn full battery retains 90% of its initial capacity after 3500 cycles at 2 A g−1, and assembled hybrid capacitor operates smoothly over 65 000 cycles at 10 A g−1. These results underscore the potential of this coating as a promising solution for achieving highly stable Zn anodes for aqueous batteries. [ABSTRACT FROM AUTHOR]

The extensively studied Prussian blue analogs (PBAs) in various batteries are limited by their low discharge capacity, or subpar rate etc. which are solely reliant on the cation (de)intercalation mechanism. In contrast to the currently predominant focus on cations, we report the overlooked anion‐cation competition chemistry (Cl−, K+, Zn2+) stimulated by high‐voltage scanning. With our designed anion‐cation combinations, the KFeMnHCF cathode battery delivers comprehensively superior discharge performance, including voltage plateau >2.0 V (vs. Zn/Zn2+), capacity >150 mAh g−1, rate capability with capacity maintenance above 96 % from 0.6 to 5 A g−1, and cyclic stability exceeding 3000 cycles. We further verify that such comprehensive improvement of electrochemical performance utilizing anion‐cation competition chemistry is universal for different types of PBAs. Our work would pave a new and efficient road towards the next‐generation high‐performance PBAs cathode batteries. [ABSTRACT FROM AUTHOR]

Compared to sp2‐hybridized graphene, graphdiynes (GDYs) composed of sp and sp2 carbon are highly promising as efficient catalysts for electrocatalytic oxygen reduction into oxygen peroxide because of the high catalytic reactivity of the electron‐rich sp‐carbon atoms. The desired catalytic capacity of GDY, such as catalytic selectivity and efficiency, can theoretically be achieved by strategically steering the sp‐carbon contents or the topological arrangement of the acetylenic linkages and aromatic bonds. Herein, we successfully tuned the electrocatalytic activity of GDYs by regulating the sp‐to‐sp2 carbon ratios with different organic monomer precursors. As the active sp‐carbon atoms possess electron‐sufficient π orbitals, they can donate electrons to the lowest unoccupied molecular orbital (LUMO) orbitals of O2 molecules and initiate subsequent O2 reduction, GDY with the high sp‐carbon content of 50 at % exhibits excellent capability of catalyzing O2 reduction into H2O2. It demonstrates exceptional H2O2 selectivity of over 95.0 % and impressive performance in practical H2O2 production, Faraday efficiency (FE) exceeding 99.0 %, and a yield of 83.3 nmol s−1 cm−2. Our work holds significant importance in effectively steering the inherent properties of GDYs by purposefully adjusting the sp‐to‐sp2 carbon ratio and highlights their immense potential for research and applications in catalysis and other fields. [ABSTRACT FROM AUTHOR]

The extensively studied Prussian blue analogs (PBAs) in various batteries are limited by their low discharge capacity, or subpar rate etc. which are solely reliant on the cation (de)intercalation mechanism. In contrast to the currently predominant focus on cations, we report the overlooked anion‐cation competition chemistry (Cl−, K+, Zn2+) stimulated by high‐voltage scanning. With our designed anion‐cation combinations, the KFeMnHCF cathode battery delivers comprehensively superior discharge performance, including voltage plateau >2.0 V (vs. Zn/Zn2+), capacity >150 mAh g−1, rate capability with capacity maintenance above 96 % from 0.6 to 5 A g−1, and cyclic stability exceeding 3000 cycles. We further verify that such comprehensive improvement of electrochemical performance utilizing anion‐cation competition chemistry is universal for different types of PBAs. Our work would pave a new and efficient road towards the next‐generation high‐performance PBAs cathode batteries. [ABSTRACT FROM AUTHOR]

Compared to sp2‐hybridized graphene, graphdiynes (GDYs) composed of sp and sp2 carbon are highly promising as efficient catalysts for electrocatalytic oxygen reduction into oxygen peroxide because of the high catalytic reactivity of the electron‐rich sp‐carbon atoms. The desired catalytic capacity of GDY, such as catalytic selectivity and efficiency, can theoretically be achieved by strategically steering the sp‐carbon contents or the topological arrangement of the acetylenic linkages and aromatic bonds. Herein, we successfully tuned the electrocatalytic activity of GDYs by regulating the sp‐to‐sp2 carbon ratios with different organic monomer precursors. As the active sp‐carbon atoms possess electron‐sufficient π orbitals, they can donate electrons to the lowest unoccupied molecular orbital (LUMO) orbitals of O2 molecules and initiate subsequent O2 reduction, GDY with the high sp‐carbon content of 50 at % exhibits excellent capability of catalyzing O2 reduction into H2O2. It demonstrates exceptional H2O2 selectivity of over 95.0 % and impressive performance in practical H2O2 production, Faraday efficiency (FE) exceeding 99.0 %, and a yield of 83.3 nmol s−1 cm−2. Our work holds significant importance in effectively steering the inherent properties of GDYs by purposefully adjusting the sp‐to‐sp2 carbon ratio and highlights their immense potential for research and applications in catalysis and other fields. [ABSTRACT FROM AUTHOR]

The rechargeable aqueous Zn||MnO2 chemistry has been extensively explored, but its electrochemical reaction mechanisms, especially in the context of MnO2/Mn2+ conversion and Zn2+/H+ intercalation chemistry, remain not fully understood. Here, we designed an amphiphilic hydrogel electrolyte, which distinguished the MnO2/Mn2+ conversion, Zn2+ intercalation, and H+ intercalation and conversion processes at three distinct discharge plateaus of an aqueous Zn||MnO2 battery. The amphiphilic hydrogel electrolyte is featured with an extended electrochemical stability window up to 3.0 V, high ionic conductivity, Zn2+‐selective ion tunnels, and hydrophobic associations with cathode materials. This specifically designed electrolyte allows the MnO2/Mn2+ conversion reaction at a discharge plateau of 1.75 V. More interesting, the discharge plateaus of ~1.33 V, previously assigned as the co‐intercalation of Zn2+ and H+ ions in the MnO2 cathode, are specified as the exclusive intercalation of Zn2+ ions, leading to an ultra‐flat voltage plateau. Furthermore, with a distinct three‐step electrochemical energy storage process, a high areal capacity of 1.8 mAh cm−2 and high specific energy of 0.858 Wh cm−2, even at a low MnO2 loading mass of 0.5 mg cm−2 are achieved. To our knowledge, this is the first report to fully distinguish different mechanisms at different potentials in aqueous Zn||MnO2 batteries. [ABSTRACT FROM AUTHOR]

The rechargeable aqueous Zn||MnO2 chemistry has been extensively explored, but its electrochemical reaction mechanisms, especially in the context of MnO2/Mn2+ conversion and Zn2+/H+ intercalation chemistry, remain not fully understood. Here, we designed an amphiphilic hydrogel electrolyte, which distinguished the MnO2/Mn2+ conversion, Zn2+ intercalation, and H+ intercalation and conversion processes at three distinct discharge plateaus of an aqueous Zn||MnO2 battery. The amphiphilic hydrogel electrolyte is featured with an extended electrochemical stability window up to 3.0 V, high ionic conductivity, Zn2+‐selective ion tunnels, and hydrophobic associations with cathode materials. This specifically designed electrolyte allows the MnO2/Mn2+ conversion reaction at a discharge plateau of 1.75 V. More interesting, the discharge plateaus of ~1.33 V, previously assigned as the co‐intercalation of Zn2+ and H+ ions in the MnO2 cathode, are specified as the exclusive intercalation of Zn2+ ions, leading to an ultra‐flat voltage plateau. Furthermore, with a distinct three‐step electrochemical energy storage process, a high areal capacity of 1.8 mAh cm−2 and high specific energy of 0.858 Wh cm−2, even at a low MnO2 loading mass of 0.5 mg cm−2 are achieved. To our knowledge, this is the first report to fully distinguish different mechanisms at different potentials in aqueous Zn||MnO2 batteries. [ABSTRACT FROM AUTHOR]

Directly electrochemical conversion of nitrate (NO3−) is an efficient and environmentally friendly technology for ammonia (NH3) production but is challenged by highly selective electrocatalysts. High‐entropy alloys (HEAs) with unique properties are attractive materials in catalysis, particularly for multi‐step reactions. Herein, we first reported the application of HEA (FeCoNiAlTi) for electrocatalytic NO3− reduction to NH3 (NRA). The bulk HEA is active for NRA but limited by the unsatisfied NH3 yield of 0.36 mg h−1 cm−2 and Faradaic efficiency (FE) of 82.66 %. Through an effective phase engineering strategy, uniform intermetallic nanoparticles are introduced on the bulk HEA to increase electrochemical active surface area and charge transfer efficiency. The resulting nanostructured HEA (n‐HEA) delivers enhanced electrochemical NRA performance in terms of NH3 yield (0.52 mg h−1 cm−2) and FE (95.23 %). Further experimental and theoretical investigations reveal that the multi‐active sites (Fe, Co, and Ni) dominated electrocatalysis for NRA over the n‐HEA. Notably, the typical Co sites exhibit the lowest energy barrier for NRA with *NH2 to *NH3as the rate‐determining step. [ABSTRACT FROM AUTHOR]

Boron nitride nanotube (BNNT)@mesoporous silica hybrids with controllable surface zeta potential were fabricated for intracellular delivery of doxorubicin. The materials showed higher suspension ability, doxorubicin intracellular endocytosis efficiency, and LNcap prostate cancer cell killing ability compared with naked BNNTs. [ABSTRACT FROM AUTHOR]

• We discussed the fundamentals of Zn electrode/electrolyte interface. • We summarized the competent strategies to fulfill a stable working Zn anode. • We outlined characterization techniques to reveal interfacial chemistries. • We provide the perspectives on the design requirements for Zn batteries. Zn metal batteries are promising for large-scale energy storage systems because of their extremely intrinsic safety and low cost. However, parasitic side reactions such as hydrogen evolution, Zn corrosion, and flourished dendrite growth behavior impede their practical implementation. Notably, electrode/electrolyte interface plays a critical role in regulating Zn deposition and improving the cyclic lifespan of rechargeable Zn metal batteries. Here, the fundamentals of Zn electrode/electrolyte interface and the related issues are discussed. Thereafter, competent strategies including artificial protective layers, electrolyte optimization, structural engineering to fulfill a stable working Zn metal anode are presented. Subsequently, progressive characterization techniques reveal interfacial chemistries and morphological evolution of Zn metal anodes are outlined. Finally, the significantly perspective to guide and promote the developed of Zn batteries are proposed. This review will serve to further advance the development of interfacial engineering for Zn metal anodes. [ABSTRACT FROM AUTHOR]

As a material possessing extremely high thermal conductivity, graphene has been considered as the ultimate filler for fabrication of highly thermally conductive polymer composites. In the past decade, graphene and its derivatives were demonstrated in many studies to be very effective in enhancing the thermal conductivity of various polymers. This paper reviews current progress in the development of graphene/polymer composites with high thermal conductivity. We began with the effects of isotopes, defects/doping, edges and substrate, polycrystallinity, functionalization, size and layer number, and folding/twisting on the thermal conductivity of graphene. We then modelled the thermal conductivity of graphene/polymer composites and, through molecular dynamics (MD) simulations, demonstrated its dependence on interfacial thermal conductance as well as size, dispersion and volume fraction of graphene. After a critique of recent studies on thermally conductive graphene/polymer composites and their potential applications, we identified several outstanding issues, new challenges and opportunities for future endeavours. [ABSTRACT FROM AUTHOR]

Boron nitride nanotubes (BNNTs) were synthesized by a carbon-free chemical vapor deposition method using boron and metal oxide as reactants. Then SnO2 nanoparticles were functionalized on them via a simple wet chemistry method. Detailed transmission electron microscopy (TEM) observations reveal that SnO2 nanoparticles may cover the tube surface or be encapsulated in tube channels. The lattice distances of both BNNT and SnO2 have been changed due to the strong interactions between them. The band gap energy of SnO2 particles is found enlarged due to the size effect and interaction with BNNTs. [ABSTRACT FROM AUTHOR]

Large quantities of highly pure boron nitride nanotubes (BNNTs) are synthesized through a carbon-free method. Nanotube phonon features are investigated by Raman and Fourier-transformed infrared spectroscopies. Both methods indicate highly pure boron nitride phase. Intense ultraviolet light emission is observed when BNNTs are excited by an electron beam, which indicates that the present BNNTs have potential applications in ultraviolet optical devices. [ABSTRACT FROM AUTHOR]

Organic additives with high‐reduction potentials are generally applied in aqueous electrolytes to stabilize the Zn anode, while compromise safety and environmental compatibility. Highly concentrated water‐in‐salt electrolytes have been proposed to realize the high reversibility of Zn plating/stripping; however, their high cost and viscosity hinder their practical applications. Therefore, exploring low‐concentration Zn salts, that can be used directly to stabilize Zn anodes, is of primary importance. Herein, we developed an asymmetric anion group, bi(difluoromethanesulfonyl)(trifluoromethanesulfonyl)imide (DFTFSI‐)‐based novel zinc salt, Zn(DFTFSI)2, to obtain a high ionic conductivity and a highly stable dendrite‐free Zn anode. Experimental tests and theoretical calculations verified that DFTFSI− in the Zn2+ solvation sheath and inner Helmholtz plane would be preferentially reduced to construct layer‐structured SEI films, inhibiting hydrogen evolution and side reactions. Consequently, the Zn|| ${||}$ Zn symmetric cell with 1M Zn(DFTFSI)2 aqueous electrolyte delivers an ultralong cycle life for >2500 h outperforming many other conventional Zn salt electrolytes. The Zn|| ${||}$ Br2 battery also exhibits a long lifespan over 1200 cycles at ~99.8 % Coulombic efficiency with a high capacity retention of 92.5 %. Furthermore, this outstanding performance translates well to a high‐areal‐capacity Zn|| ${||}$ Br2 battery (~5.6 mAh ⋅ cm‐2), cycling over 320 cycles with 95.3 % initial capacity retained. [ABSTRACT FROM AUTHOR]

Organic additives with high‐reduction potentials are generally applied in aqueous electrolytes to stabilize the Zn anode, while compromise safety and environmental compatibility. Highly concentrated water‐in‐salt electrolytes have been proposed to realize the high reversibility of Zn plating/stripping; however, their high cost and viscosity hinder their practical applications. Therefore, exploring low‐concentration Zn salts, that can be used directly to stabilize Zn anodes, is of primary importance. Herein, we developed an asymmetric anion group, bi(difluoromethanesulfonyl)(trifluoromethanesulfonyl)imide (DFTFSI‐)‐based novel zinc salt, Zn(DFTFSI)2, to obtain a high ionic conductivity and a highly stable dendrite‐free Zn anode. Experimental tests and theoretical calculations verified that DFTFSI− in the Zn2+ solvation sheath and inner Helmholtz plane would be preferentially reduced to construct layer‐structured SEI films, inhibiting hydrogen evolution and side reactions. Consequently, the Zn|| ${||}$ Zn symmetric cell with 1M Zn(DFTFSI)2 aqueous electrolyte delivers an ultralong cycle life for >2500 h outperforming many other conventional Zn salt electrolytes. The Zn|| ${||}$ Br2 battery also exhibits a long lifespan over 1200 cycles at ~99.8 % Coulombic efficiency with a high capacity retention of 92.5 %. Furthermore, this outstanding performance translates well to a high‐areal‐capacity Zn|| ${||}$ Br2 battery (~5.6 mAh ⋅ cm‐2), cycling over 320 cycles with 95.3 % initial capacity retained. [ABSTRACT FROM AUTHOR]

Stretchable energy storage devices (SESDs) are indispensable as power a supply for next‐generation independent wearable systems owing to their conformity when applied on complex surfaces and functionality under mechanical deformation. Structural strategies with underlying fundamental mechanics to achieve stretchability and material synthesis for stretchable electrodes and separators as building blocks in the fabrication of SESDs are briefly introduced in this review. Representative SESDs including stretchable supercapacitors and stretchable Li‐based and Zn‐based batteries are also summarized from the perspective of design strategy and performance optimization in terms of voltage output, energy density and capacity retention under mechanical strain. Finally, challenges and future development directions in this promising field are presented. [ABSTRACT FROM AUTHOR]

Zn‐ion batteries are regarded as the most promising batteries for next‐generation, large‐scale energy storage because of their low cost, high safety, and eco‐friendly nature. The use of aqueous electrolytes results in poor reversibility and leads to many challenges related to the Zn anode. Electrolyte additives can effectively address many such challenges, including dendrite growth and corrosion. This review provides a comprehensive introduction to the major challenges in and current strategies used for Zn anode protection. In particular, an in‐depth and fundamental understanding is provided of the various functions of electrolyte additives, including electrostatic shielding, adsorption, in situ solid electrolyte interphase formation, enhancing water stability, and surface texture regulation. Potential future research directions for electrolyte additives used in aqueous Zn‐ion batteries are also discussed. [ABSTRACT FROM AUTHOR]

High iodine loading and high‐temperature adaptability of the iodine cathode are prerequisites to achieving high energy density at full battery level and promoting the practical application for the zinc‐iodine (Zn‐I2) battery. However, it would aggravate the polyiodide shuttle effect when employing high iodine loading and working temperature. Here, a sustainable cationic cellulose nanofiber (cCNF) was employed to confine the active iodine species through strong physiochemical adsorption to enlarge the iodine loading and stabilize it even at high temperatures. The cCNF could accommodate dual‐functionality by enlarging the iodine loading and suppressing the polyiodide shuttle effect, owing to the unique framework structure with abundant surface positive charges. As a result, the iodine cathode based on the cCNF could deliver high iodine mass loading of 14.1 mg cm−2 with a specific capacity of 182.7 mAh g−1, high areal capacity of 2.6 mAh cm−2, and stable cycling over 3000 cycles at 2 A g−1, thus enabling a high energy density of 34.8 Wh kg−1 and the maximum power density of 521.2 W kg−1 at a full Zn‐I2 battery level. In addition, even at a high temperature of 60 °C, the Zn‐I2 battery could still deliver a stable cycling. [ABSTRACT FROM AUTHOR]

High iodine loading and high‐temperature adaptability of the iodine cathode are prerequisites to achieving high energy density at full battery level and promoting the practical application for the zinc‐iodine (Zn‐I2) battery. However, it would aggravate the polyiodide shuttle effect when employing high iodine loading and working temperature. Here, a sustainable cationic cellulose nanofiber (cCNF) was employed to confine the active iodine species through strong physiochemical adsorption to enlarge the iodine loading and stabilize it even at high temperatures. The cCNF could accommodate dual‐functionality by enlarging the iodine loading and suppressing the polyiodide shuttle effect, owing to the unique framework structure with abundant surface positive charges. As a result, the iodine cathode based on the cCNF could deliver high iodine mass loading of 14.1 mg cm−2 with a specific capacity of 182.7 mAh g−1, high areal capacity of 2.6 mAh cm−2, and stable cycling over 3000 cycles at 2 A g−1, thus enabling a high energy density of 34.8 Wh kg−1 and the maximum power density of 521.2 W kg−1 at a full Zn‐I2 battery level. In addition, even at a high temperature of 60 °C, the Zn‐I2 battery could still deliver a stable cycling. [ABSTRACT FROM AUTHOR]

The practical use of Zn metal anodes in aqueous zinc batteries is impeded by the growth of dendrites, anode corrosion, and hydrogen evolution reaction in aqueous electrolytes. In this study, a simple, energy‐efficient, and scalable approach is reported to mitigate these detrimental issues effectively. Using 1‐hexanethiol (HT), a hydrophobic self‐assembled mercaptan layer (SAML) with a highly ordered structure is in situ created on the surface of the Zn anode. This ultrathin interfacial structure guides uniform Zn deposition and shields the Zn anode from water and oxygen‐induced corrosion, thus effectively inhibiting dendrite formation and side reactions. Consequently, the HT‐Zn electrode showcases impressive electrochemical stability and reversibility, and the as‐assembled HT‐Zn||I2 full cell delivers increased specific capacity (from 112 to 155 mAh g−1 at 1 A g−1) and ultra‐stable cyclability (zero capacity decay during the extended 1500 cycles at 4 A g−1). To validate the effectiveness of this simple and scalable method, a large‐sized pouch cell is prepared, which can be stably operated for 1000 cycles with a capacity decay of merely 0.0098% per cycle and Coulombic efficiency exceeding 99.1%. The presented SAML strategy highlights the potential of molecular engineering in improving the performance of aqueous zinc batteries. [ABSTRACT FROM AUTHOR]

Rechargeable aqueous calcium‐ion batteries (CIBs) are promising for reliable large‐scale energy storage. However, they face significant challenges, primarily stemming from suboptimal anodes, resulting in unfavorable voltage profiles, limited capacity, and diminished durability, all of which hinder the development of CIBs. Here, a covalent organic framework (PTHAT‐COF) featuring repeated pyrazine and pyridinamine units, employed as the anode material for aqueous CIBs, is introduced. This innovative approach results in a remarkably flat ultralow potential plateau ranging from −0.6 to −1.05 V (vs Ag/AgCl), attributed to the high level of the lowest unoccupied molecular orbital. Furthermore, the PTHAT‐COF anode exhibits outstanding rate performance (152.3 mAh g−1 @ 1 A g−1), exceptional long‐term cycling stability, and remarkable capacity retention (10 000 cycles with 89.9% retention). Mechanistic studies, including experimental and theoretical calculations, reveal that C═N active sites reversibly trap Ca2+ ions via chemisorption during the discharging/charging process. The PTHAT‐COF demonstrates exceptional structural stability throughout cycling. Finally, by pairing PTHAT‐COF with a high‐voltage manganese‐based Prussian blue cathode, a complete aqueous CIB with a voltage interval of 2.2 V is achieved, exhibiting extraordinary durability (10 000 cycles with 83.6% retention). This research illuminates the potential of organic anode materials in aqueous batteries to achieve higher battery voltages. [ABSTRACT FROM AUTHOR]

Zinc batteries hold promise for grid‐scale energy storage due to their safety and low cost. A key challenge for the field is identifying cathode materials that can undergo reversible redox reactions at the extreme potentials required for realizing high energy density devices. While organic materials have been extensively explored as cathode materials due to their structural tunability and eco‐friendliness, most reported zinc‐organic batteries exhibit a voltage lower than 1.2 V. In this report, by employing rational molecular design and synthesis, computational analysis, and electrochemical evaluation, the well‐studied neutral p‐type N‐centered is redesigned, triphenylamine organic cathode by replacing three phenyl rings with the smallest aromatic system – cationic cyclopropenium. This results in a novel class of cathode materials with simultaneously enhanced potential, capacity, and stability. The resultant full battery exhibits a high discharge voltage of 1.7 V and an outstanding capacity retention of 95% after 10000 cycles at a discharge capacity of 157.5 mAh g−1cation (103.9 mAh g−1salt). [ABSTRACT FROM AUTHOR]

Metal–organic framework‐based materials are promising single‐site catalysts for electrocatalytic nitrate (NO3−) reduction to value‐added ammonia (NH3) on account of well‐defined structures and functional tunability but still lack a molecular‐level understanding for designing the high‐efficient catalysts. Here, we proposed a molecular engineering strategy to enhance electrochemical NO3−‐to‐NH3 conversion by introducing the carbonyl groups into 1,2,4,5‐tetraaminobenzene (BTA) based metal‐organic polymer to precisely modulate the electronic state of metal centers. Due to the electron‐withdrawing properties of the carbonyl group, metal centers can be converted to an electron‐deficient state, fascinating the NO3− adsorption and promoting continuous hydrogenation reactions to produce NH3. Compared to CuBTA with a low NO3−‐to‐NH3 conversion efficiency of 85.1 %, quinone group functionalization endows the resulting copper tetraminobenzoquinone (CuTABQ) distinguished performance with a much higher NH3 FE of 97.7 %. This molecular engineering strategy is also universal, as verified by the improved NO3−‐to‐NH3 conversion performance on different metal centers, including Co and Ni. Furthermore, the assembled rechargeable Zn−NO3− battery based on CuTABQ cathode can deliver a high power density of 12.3 mW cm−2. This work provides advanced insights into the rational design of metal complex catalysts through the molecular‐level regulation for NO3− electroreduction to value‐added NH3. [ABSTRACT FROM AUTHOR]

Metal–organic framework‐based materials are promising single‐site catalysts for electrocatalytic nitrate (NO3−) reduction to value‐added ammonia (NH3) on account of well‐defined structures and functional tunability but still lack a molecular‐level understanding for designing the high‐efficient catalysts. Here, we proposed a molecular engineering strategy to enhance electrochemical NO3−‐to‐NH3 conversion by introducing the carbonyl groups into 1,2,4,5‐tetraaminobenzene (BTA) based metal‐organic polymer to precisely modulate the electronic state of metal centers. Due to the electron‐withdrawing properties of the carbonyl group, metal centers can be converted to an electron‐deficient state, fascinating the NO3− adsorption and promoting continuous hydrogenation reactions to produce NH3. Compared to CuBTA with a low NO3−‐to‐NH3 conversion efficiency of 85.1 %, quinone group functionalization endows the resulting copper tetraminobenzoquinone (CuTABQ) distinguished performance with a much higher NH3 FE of 97.7 %. This molecular engineering strategy is also universal, as verified by the improved NO3−‐to‐NH3 conversion performance on different metal centers, including Co and Ni. Furthermore, the assembled rechargeable Zn−NO3− battery based on CuTABQ cathode can deliver a high power density of 12.3 mW cm−2. This work provides advanced insights into the rational design of metal complex catalysts through the molecular‐level regulation for NO3− electroreduction to value‐added NH3. [ABSTRACT FROM AUTHOR]

Multivalent ion batteries (e.g., Zn2+, Ca2+) are gaining great attention owing to their potentially high capacity, cheap cost, and good safety. However, significant disparities exist in achieved capacity, voltage, and kinetic performance within zinc and calcium ion electrolytes. Herein, the electrochemical and kinetic properties of Zn2+ and Ca2+ in aqueous electrolytes are investigated using a single‐crystal V2O5 (V2O5·Pyridine, PVO) model material with stable large interlayer spacing. It is found that the discharge‐specific capacity in 1 m Zn(ClO4)2 aqueous solution is 247.3 mAh g−1 at 0.3 A g−1, which is remarkably higher than 158.4 mAh g−1 in 1 m Ca(ClO4)2. Mechanistic studies show that in aqueous ZIB, H+ is intercalated first, followed by the generation of Zn4(OH)7ClO4, and finally H+ and Zn2+ are co‐intercalated. But in aqueous CIB, H+ dominates the intercalation process. It is found that six times more Zn2+ than Ca2+ is intercalated into PVO, owing to its smaller radii and its relative higher intercalation potential (Zn2+ @‐0.34 V, Ca2+ @‐0.65 V vs.. Ag/AgCl), giving it a higher specific capacity. Furthermore, density functional theory calculations demonstrate lower intercalation energies for Ca2+ (−6.67 eV) compared to Zn2+ (−1.85 eV), explaining the lower intercalation potential of Ca2+. [ABSTRACT FROM AUTHOR]

Insufficient and unstable energy output is the bottleneck issue radically restricting the application of micro‐supercapacitors (MSCs). Herein, an interlayer atom injection strategy that can anchor low‐valence Zn atoms (Znδ+, 0 < δ <2) on O‐terminals of Ti3C2Tx (MXene) flakes within the MXene/silver‐nanowires hybrid cathode of symmetric MSCs is first presented. Combining the polyacrylamide/ZnCl2 hydrogel electrolyte rich in Cl− and Zn2+ ions, the matched Znδ+/Zn2+ (−0.76 V vs SHE) and Ag/AgCl (0.23 V vs SHE), redox couples between the symmetrical electrodes are activated to offer faradaic charge storage beside ions‐intercalation involved pseudocapacitance. Thus, a battery‐type voltage plateau (≈0.9 V) appears in the discharge curve of a fabricated pseudo‐symmetric micro‐redox capacitor, simultaneously achieving energy density enhancement (117 µWh cm−2 at 0.5 mA cm−2) and substantially improved power output stability (46% of the energy from the plateau region) relative to that before activation (98 µWh cm−2 without voltage platform). The work provides a fire‐new strategy to overcome the performance bottlenecks confronting conventional MSCs. [ABSTRACT FROM AUTHOR]

Conversion‐type batteries apply the principle that more charge transfer is preferable. The underutilized electron transfer mode within two undermines the electrochemical performance of halogen batteries. Here, we realised a three‐electron transfer lithium‐halogen battery based on I−/I+ and Cl−/Cl0 couples by using a common commercial electrolyte saturated with Cl− anions. The resulting Li||tetrabutylammonium triiodide (TBAI3) cell exhibits three distinct discharging plateaus at 2.97, 3.40, and 3.85 V. Moreover, it has a high capacity of 631 mAh g−1I (265 mAh g−1electrode, based on entire mass loading) and record‐high energy density of up to 2013 Wh kg−1I (845 Wh kg−1electrode). To support these findings, experimental characterisations and density functional theory calculations were conducted to elucidate the redox chemistry involved in this novel interhalogen strategy. We believe our paradigm presented here has a foreseeable inspiring effect on other halogen batteries for high‐energy‐density pursuit. [ABSTRACT FROM AUTHOR]

Conversion‐type batteries apply the principle that more charge transfer is preferable. The underutilized electron transfer mode within two undermines the electrochemical performance of halogen batteries. Here, we realised a three‐electron transfer lithium‐halogen battery based on I−/I+ and Cl−/Cl0 couples by using a common commercial electrolyte saturated with Cl− anions. The resulting Li||tetrabutylammonium triiodide (TBAI3) cell exhibits three distinct discharging plateaus at 2.97, 3.40, and 3.85 V. Moreover, it has a high capacity of 631 mAh g−1I (265 mAh g−1electrode, based on entire mass loading) and record‐high energy density of up to 2013 Wh kg−1I (845 Wh kg−1electrode). To support these findings, experimental characterisations and density functional theory calculations were conducted to elucidate the redox chemistry involved in this novel interhalogen strategy. We believe our paradigm presented here has a foreseeable inspiring effect on other halogen batteries for high‐energy‐density pursuit. [ABSTRACT FROM AUTHOR]

Review: [62 refs. [ABSTRACT FROM AUTHOR]

Due to the high abundance of their components, low cost, and high safety, zinc‐based batteries open up new vistas for large‐scale energy storage. However, their stability, lifetime, and reversibility are impaired by passivation and dendrite growth of the Zn anode. Here, this challenge is circumvented by an iodine post‐functionalized zeolitic imidazolate framework‐90 (ZIF‐90‐I) additive, in which the polycation absorbed on Zn anode can regulate solid–electrolyte interphase (SEI) formation in the 1 m Zn(TFSI)2 electrolyte and induce Zn2+ uniform deposition. Moreover, the I3−/I− redox can rejuvenate dead Zn and inhibit dendrites. With the ZIF‐90‐I additive, Zn plating/stripping at 99.5% Coulombic efficiency for 120 cycles is obtained in Zn||Ti cells at 20 mA cm−2/1 mAh cm−2. In addition, Zn||Zn cells show steady cycling for 1200 h at 5 mA cm−2/1 mAh cm−2 with stable overpotentials. The utilization rate of Zn reaches up to 68.6%. In situ optical microscopy reveals smooth, uniform Zn plating, and the Zn‐rejuvenated function from the I3−/I− redox couple. The refreshed SEI with the increase of Zn‐rich complexes, and nitrides from adsorbed polycations, are uniform and ZnF2‐rich in the Zn(TFSI)2 + ZIF‐90‐I electrolyte. The full Zn||air cells in Zn(TFSI)2 + ZIF‐90‐I electrolyte exhibit excellent cycling stability with stable polarization voltage at 0.1 mA/0.05 mAh cm−2. [ABSTRACT FROM AUTHOR]

Aqueous metal‐iodine batteries have recently attracted widespread attention, but their intrinsic issues such as the undesired shuttle effect and volatility of iodine hinder their reliable long‐term performance. Herein, organic–inorganic MXDA2SnI6 (MXDA2+ denotes protonated m‐xylylenediamine cation) perovskite microcrystals with a zero‐dimensional arrangement of octahedral perovskite units offering high content of elemental iodine (46 wt% in the whole cathode) are proposed as conversion‐type cathode materials for aqueous ZnI2 batteries. Iodide anions deliver reliable electrochemical activity and are effectively immobilized on the cathode to relieve the shuttle process by both physical steric hindrance and chemical adsorption offered by long‐chain organic matrix and the presence of B‐site Sn(II) cations in the MXDA2SnI6 perovskite, respectively. Moreover, the formation of triiodide anions is alleviated in favor of a significant proportion of pentaiodide ions during the end of the charging process, enabled by increased formation energy of I3− and effective confinement via SnI...I halogen bonds and NH...I hydrogen bonds, as revealed by density functional theory calculations. As a result, rechargeable aqueous ZnI2 batteries are realized that achieve a champion capacity of over 206 mAh g−1I at 0.5 A g−1 (close to the theoretical limit), and outstanding rate capability with a capacity retention of 87% at 3 A g−1. Suppressed shuttle of polyiodide anions endows aqueous ZnI2 batteries with prolonged cyclic stability, namely high capacity retention of 95% after 5700 cycles at 1 A g−1. This study promotes the development of high‐performance cathode materials for metal‐I2 batteries by revealing the feasibility of using ionic perovskites as conversion‐type cathodes. [ABSTRACT FROM AUTHOR]

Electrolyte environments, including cations, anions, and solvents are critical for the performance delivery of cathodes of batteries. Most works focused on interactions between cations and cathode materials, in contrast, there is a lack of in‐depth research on the correlation between anions and cathodes. Here, we systematically investigated how anions manipulate the coulombic efficiency (CE) of cathodes of zinc batteries. We take intercalation‐type V2O5 and conversion‐type I2 cathodes as typical cases for profound studies. It was found that electronic properties of anions, including charge density and its distribution, can tune conversion or intercalation reactions, leading to significant CE differences. Using operando visual Raman microscopy and theoretical simulations, we confirm that competitive coordination between anions and I− can regulate CEs by modulating polyiodide diffusion rates in Zn−I2 cells. In Zn−V2O5 cells, anion‐tuned solvation structures vastly affect CEs through varying Zn2+ intercalation kinetics. Conversion I2 cathode achieves a 99 % CE with highly electron‐donating anions, while anions with preferable charge structures that interact strongly with Zn2+ afford an intercalation V2O5 a nearly 100 % CE. Understanding the mechanism of anion‐governed CEs will help us evaluate compatibility of electrolytes with electrodes, thus providing a guideline for anion selection and electrolyte design for high‐energy, long‐cycling zinc batteries. [ABSTRACT FROM AUTHOR]

Constructing a reliable solid‐electrolyte interphase (SEI) is imperative for enabling highly reversible zinc metal (Zn0) electrodes. Contrary to conventional "bulk solvation" mechanism, we found the SEI structure is dominated by electric double layer (EDL) adsorption. We manipulate the EDL adsorption and Zn2+ solvation with ether additives (i.e. 15‐crown‐5, 12‐crown‐4, and triglyme). The 12‐crown‐4 with medium adsorption on EDL leads to a layer‐structured SEI with inner inorganic ZnFx/ZnSx and outer organic C−O−C components. This structure endows SEI with high rigidness and strong toughness enabling the 100 cm2 Zn||Zn pouch cell to exhibit a cumulative capacity of 4250 mAh cm−2 at areal‐capacity of 10 mAh cm−2. More importantly, a 2.3 Ah Zn||Zn0.25V2O5⋅n H2O pouch cell delivers a recorded energy density of 104 Wh Lcell−1 and runs for >70 days under the harsh conditions of low negative/positive electrode ratio (2.2 : 1), lean electrolyte (8 g Ah−1), and high‐areal‐capacity (≈13 mAh cm−2). [ABSTRACT FROM AUTHOR]

Electrolyte environments, including cations, anions, and solvents are critical for the performance delivery of cathodes of batteries. Most works focused on interactions between cations and cathode materials, in contrast, there is a lack of in‐depth research on the correlation between anions and cathodes. Here, we systematically investigated how anions manipulate the coulombic efficiency (CE) of cathodes of zinc batteries. We take intercalation‐type V2O5 and conversion‐type I2 cathodes as typical cases for profound studies. It was found that electronic properties of anions, including charge density and its distribution, can tune conversion or intercalation reactions, leading to significant CE differences. Using operando visual Raman microscopy and theoretical simulations, we confirm that competitive coordination between anions and I− can regulate CEs by modulating polyiodide diffusion rates in Zn−I2 cells. In Zn−V2O5 cells, anion‐tuned solvation structures vastly affect CEs through varying Zn2+ intercalation kinetics. Conversion I2 cathode achieves a 99 % CE with highly electron‐donating anions, while anions with preferable charge structures that interact strongly with Zn2+ afford an intercalation V2O5 a nearly 100 % CE. Understanding the mechanism of anion‐governed CEs will help us evaluate compatibility of electrolytes with electrodes, thus providing a guideline for anion selection and electrolyte design for high‐energy, long‐cycling zinc batteries. [ABSTRACT FROM AUTHOR]

Constructing a reliable solid‐electrolyte interphase (SEI) is imperative for enabling highly reversible zinc metal (Zn0) electrodes. Contrary to conventional "bulk solvation" mechanism, we found the SEI structure is dominated by electric double layer (EDL) adsorption. We manipulate the EDL adsorption and Zn2+ solvation with ether additives (i.e. 15‐crown‐5, 12‐crown‐4, and triglyme). The 12‐crown‐4 with medium adsorption on EDL leads to a layer‐structured SEI with inner inorganic ZnFx/ZnSx and outer organic C−O−C components. This structure endows SEI with high rigidness and strong toughness enabling the 100 cm2 Zn||Zn pouch cell to exhibit a cumulative capacity of 4250 mAh cm−2 at areal‐capacity of 10 mAh cm−2. More importantly, a 2.3 Ah Zn||Zn0.25V2O5⋅n H2O pouch cell delivers a recorded energy density of 104 Wh Lcell−1 and runs for >70 days under the harsh conditions of low negative/positive electrode ratio (2.2 : 1), lean electrolyte (8 g Ah−1), and high‐areal‐capacity (≈13 mAh cm−2). [ABSTRACT FROM AUTHOR]

Polymer blends based solid polymer electrolytes (SPEs), combining the advantages of multiple polymers, are promising for the utilization of 5 V‐class cathodes (e.g., LiCoMnO4 (LCMO)) with enhanced safety. However, severe macro‐phase separation with defects and voids in polymer blends restrict the electrochemical stability and ionic migration of SPEs. Herein, inorganic compatibilizer polyacrylonitrile grafted MXene (MXene‐g‐PAN) is exploited to improve the miscibility of the poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVHF)/PAN blends and suppress the consolidation of phase particles. The resulting SPE exhibits a high anodic stability with an ionic conductivity of 2.17 × 10−4 S cm−1, enabling a stable and reversible Li platting/stripping (over 2500 h). The fabricated solid Li‖LCMO cell delivers a 5.1 V discharge voltage with a decent capacity (131 mAh g−1) and cycling performance. Subsequently, the solid all‐in‐one graphite‖LCMO battery is also constructed to extend the application of MXene based SPEs in flexible batteries. Benefiting from the interface‐less design, outstanding mechanical flexibility and stability is achieved in the battery, which can endure various deformations with a low‐capacity loss (< ≈10%). This study signifies a significant development on solid flexible lithium ion batteries with enhanced performance, stability, and reliability by investigating the miscibility of polymer blends, benefiting for the design of high‐performance SPEs. [ABSTRACT FROM AUTHOR]

[Display omitted] Electrochemical nitrate reduction reaction (NO 3 RR) is a promising alternative technique for NH 3 generation toward the energy-consuming Haber-Bosch process. Nevertheless, it remains hindered by the competitive hydrogen evolution reaction (HER). Herein, the piezoelectric effect of electron-rich BaTiO 3 with oxygen vacancies is introduced to promote NO 3 RR performance. Combining with metal particles (Ru, Pd and Pt), the catalyst achieves a maximal Faradaic efficiency of 95.3% and NH 3 yield rate of 6.87 mg h−1 mg cat. −1. Upon piezoelectricity, the interface between metal nanoparticles and BaTiO 3 is effectively modulated from Schottky contact to ohmic contact, which leads to unobstructed electron transfer. Abundant hydrogen radicals (·H) can be then produced from the collision between plentiful electrons and polar water molecules adsorbed on the polar surface. Such ·H can significantly facilitate the hydrogenation of reaction intermediates in NO 3 RR. Meanwhile, this process suppresses the Volmer-Heyrovsky step, therefore inhibiting the HER within a wide range of external potential. This work suggests a new strategy for promoting the performance of multi-electron-involved catalytic reactions. [ABSTRACT FROM AUTHOR]

Zn metal anodes that are compatible with aqueous electrolytes open the door to developing safe and cost-effective rechargeable Zinc based batteries (RZBs). However, the Commercialization of RZBs requires efforts from multiple dimensions. In this study, the temperature dependence of the Zn metal anode's lifespan is in reverse with the Li metal anode counterpart. key factors that affect the temperature sensibility of the metal anode were summarized. Based on that, we demonstrate that adjusting the electrolyte composition can customize the nominal operation temperature and balance the battery performance. [Display omitted] The operating temperature of batteries is an essential consideration in actual applications. Understanding the temperature dependence is conducive to battery design. The experience in lithium-ion batteries (LIBs) indicates that the dendrite issue is exacerbated at lower temperatures and suppressed at higher temperatures. In this study, we revealed the dendrite evolution in aqueous rechargeable zinc-based batteries (RZBs), for which the opposite temperature dependence was observed. Detailed investigations elucidate that the degree of matching of the interface reaction rate and ion diffusivity, together with side reactions, are the key factors that determine the cycling performance. The different properties of organic and aqueous electrolytes result in a reversed temperature dependence. We further conducted a detailed investigation of hybrid electrolytes (organic and aqueous) for balancing the ion diffusivity and side reactions to broaden the working temperature window for RZBs. This work reveals a completely opposite temperature dependence for LIBs and RZBs and discloses the underlying mechanism, reminding one of the differences between LIBs and RZBs in many aspects. [ABSTRACT FROM AUTHOR]

Though massive efforts have been devoted to exploring Br‐based batteries, the highly soluble Br2/Br3− species causing rigorous "shuttle effect", leads to severe self‐discharge and low Coulombic efficiency. Conventionally, quaternary ammonium salts such as methyl ethyl morpholinium bromide (MEMBr) and tetrapropylammonium bromide (TPABr) are used to fix Br2 and Br3−, but they occupy the mass and volume of battery without capacity contribution. Here, we report an all‐active solid interhalogen compound, IBr, as a cathode to address the above challenges, in which the oxidized Br0 is fixed by iodine (I), thoroughly eliminating cross‐diffusing Br2/Br3− species during the whole charging and discharging process. The Zn||IBr battery delivers remarkably high energy density of 385.8 Wh kg−1, which is higher than those of I2, MEMBr3, and TPABr3 cathodes. Our work provides new approaches to achieve active solid interhalogen chemistry for high‐energy electrochemical energy storage devices. [ABSTRACT FROM AUTHOR]