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The practical applications of aqueous Zn/I2 batteries (AZIBs) operating within a wide temperature range are severely hindered by the uncontrolled shutting of polyiodide ions (I3−/ I5−) and rampant side reactions. In this study, a wide temperature tolerant polyanionic hydrogel (borax‐bacteria cellulose / p(AMPS‐AM)) with ion selective permeability is designed for inhibiting shutting effect and side reactions under extreme temperatures range from −50 to 50 °C. The zincophilic R−SO3− significantly enhances the transport of Zn2+ cations and promotes uniform growth of Zn metal along the (002) plane. Moreover, the abundant hydrophilic groups in hydrogels effectively suppress both the hydrogen evolution reaction and the formation of by‐products by reducing the water reactivity. Furthermore, theoretical calculations, visualization experiment and in situ Raman spectroscopy confirm that R−SO3− group effectively hinders the shuttle process of I3−/I5− anions through electrostatic repulsion. Consequently, this gel electrolyte facilitates the ultra‐stable Zn/I2 full cell at a low current density of 2 C over a wide temperature range of 100 °C. A Zn/I2 pouch cell with a low negative/positive capacity ratio of 3.3 exhibits a stable performance over 350 cycles with an impressive high‐areal capacity of 2.03 mA h cm−2, thereby establishing a solid foundation for its practical applications. [ABSTRACT FROM AUTHOR]

Sodium‐ion batteries (SIBs) with wide operating temperature are regarded as promising candidates for large‐scale energy storage systems. However, SIBs operating under elevated temperature aggravate the electrolyte decomposition with unstable cathode‐electrolyte interphase (CEI), causing a rapid capacity degradation. Herein, anion receptor tris(pentafluorophenyl)borane (TPFPB) is selected as electrolyte additive to construct robust NaF‐rich CEI. The strong interactions between anion and TPFPB via the electron‐deficient boron atoms weaken ClO4− solvation and promote the coordination capability between solvents and Na+ cations, demonstrating greatly improved oxidative stability. Na3V2(PO4)3 cathode in TPFPB‐containing electrolyte delivers long‐term stability with a capacity retention of 86.9% after 100 cycles at a high cut‐off voltage of 4.2 V (vs. Na+/Na) and a high temperature of 60 °C. Besides, TPFPB also works well with enhanced performance over a temperature range from −30 to 60 °C. This study proposes a prospective method by manipulating the solvation chemistry for constructing high‐temperature rechargeable SIBs. [ABSTRACT FROM AUTHOR]

Carbon with few active sites and narrow interlayer distance as anode for potassium ion batteries (PIBs) always shows low capacity, sluggish kinetics, and low Columbic efficiency. Herein, poly(2‐aminothiazole) (P2AT) hollow nanospheres are first synthesized as a carbon source for high N, S co‐doped carbon hollow nanospheres (NS‐HCSs). The hollow P2AT nanospheres can be controllably synthesized with an Ostwald ripening process. The unique doping and structure endow the NS‐HCSs with high content of N and S dopants in carbon, mesoporous structure with enlarged interlayer distance, elevated ratio of N‐6 and N‐5 species, enhanced conductivity, abundant surface defects, and large active sites. When evaluated as an anode for PIBs, NS‐HCSs exhibit a high reversible capacity of 422 mAh g‒1 and excellent long‐term cycling performance. Using combined experiment and theoretical computation, including in situ TEM and in situ Raman, the K‐storage mechanism and dynamic evolution processes of NS‐HCSs, including low volume expansion, enhanced K‐ion adsorption, and stable composition and structure evolution during repeating potassiation/de‐potassiation processes is revealed. This quantitative design for highly durable K‐storage and large capacity in carbon can be advantageous for the rational design of anode materials of PIBs with ideal electrochemical performance. [ABSTRACT FROM AUTHOR]

Aqueous zinc ion batteries (AZIBs) with high safety, low cost, and eco‐friendliness advantages show great potential in large‐scale energy storage systems. However, their practical application is hindered by low Columbic efficiency and unstable zinc anode resulting from the side reactions and deterioration of zinc dendrites. Herein, tripropylene glycol (TG) is chosen as a dual‐functional organic electrolyte additive to improve the reversibility of AZIBs significantly. Importantly, ab initio molecular dynamics theoretical simulations and experiments such as in situ electrochemical impedance spectroscopy, and synchrotron radiation‐based in situ Fourier transform infrared spectroscopy confirm that TG participates in the solvation sheath of Zn2+, regulating overpotential and inhibiting side reactions; meanwhile, TG inhibits the deterioration of dendrites and modifies the direction of zinc deposition by constructing an adsorbed layer on the zinc anode. Consequently, a Zn‐MnO2 full cell with TG electrolyte exhibited a specific capacity of 124.48 mAh g‐1 after 1000 cycles at a current density of 4 A g‐1. This quantitative regulation for suitable solvation sheath and adsorbed layer on zinc anode, and its easy scalability of the process can be of immediate benefit for the dendrite‐free, high‐performance, and low‐cost energy storage systems. [ABSTRACT FROM AUTHOR]

Small molecule organic materials have been considered promising candidates as cathodes in aqueous zinc‐ion batteries (AZIBs) because of their low cost, environmental friendliness, and sustainable production. However, the rapid capacity fading and sluggish kinetics restrict their practical applications, especially under extremely low temperatures (−50 °C). Here, by the condensation of hexaketocyclohexane octahydrate (HKCO) and 1, 2‐diaminoanthraquinone (DQ), a fully conjugated organic molecule, anthraquinone‐quinoxaline derivative (HATAN) is prepared. With the fully conjugated structure, HATAN possesses enhanced π‐electron delocalization and strong intermolecular interaction, which ensure superior electronic conductivity and physicochemical/electrochemical stability. Additionally, the introduction of multiple redox‐active sites (C═O and C═N) can increase the theoretical capacity of HATAN. Consequently, the HATAN cathode for AZIBs exhibits remarkable capacity, long lifespan, and high‐rate capability. Even at −50  C, an exceptional capacity of 75.4 mAh g−1 and 98% capacity retention over 1500 cycles can be preserved. This study presents valuable insights into the structure design of small molecule organic cathodes for advanced AZIBs which can efficiently operate at −50 °C. [ABSTRACT FROM AUTHOR]

Zn‐I2 batteries suffer from uncontrollable shuttle effects of polyiodine ions (I3− and I5−) at the cathode/electrolyte interface and side reactions induced by reactive H2O at the anode/electrolyte interface. In this study, a hydrated eutectic electrolyte is designed that synergizes the eutectic network and functional interfacial adsorbed layer to develop high‐performance Zn‐I2 batteries. The eutectic network can restrain active H2O molecules in the electrolyte to inhibit the side reaction at the anode/electrolyte interface and shuttle effect at the cathode/electrolyte interface. Additionally, the functional interfacial adsorbed layer guides the nucleation behavior of Zn2+ to inhibit the growth of dendrites and also separates the zinc anode from direct contact with active H2O molecules and polyiodine ions to inhibit corrosion. Theoretical calculation, in situ Ultraviolet–visible spectroscopy (UV‐vis) and Raman characterizations, and visualization experiments demonstrate that the hydrated eutectic electrolyte effectively inhibits the shuttling effect and improves the reversibility of zinc deposition/stripping behavior. Consequently, the Zn‐I2 battery can maintain a capacity of 133 mAh g−1 after 5000 cycles at 5 C. This highly efficient synergistic strategy offers a practical approach to the development of advanced Zn‐I2 batteries. [ABSTRACT FROM AUTHOR]

Sodium‐ion batteries (SIBs) are a promising candidate for large‐scale energy storage due to the low cost and abundant sodium resources. However, the formation of sodium dendrites on the surface of hard carbon (HC) anodes is the most intractable challenge for full cells during charging, leading to severe performance degradation and safety hazards. Here, a robust additive‐induced borate and fluoride‐rich interphase is constructed by introducing sodium difluoro(oxalato)borate (NaDFOB) as additive in the ether‐based electrolyte to relieve the performance deterioration for SIBs. NaDFOB can participate in the passivation process of electrolyte‐electrode interfaces through preferential oxidation and reduction of DFOB− to effectively restrain the growth of sodium dendrites. Moreover, the electrolyte decomposition and dissolution of transition metal ions are effectively inhibited. Benefiting from that, FeMn‐based Prussian blue (FeMnHCF) || HC full cell with a negative/positive capacity ratio (N/P ratio) of 1.09 displays a capacity retention of 82.1%, especially with a low N/P ratio of 0.96 the cell still demonstrates a stable Coulombic efficiency of over 99.9% after 500 cycles via using NaDFOB as additive. As a practical demonstration, the designed 18650 full cells display enhanced cycling stability with NaDFOB additive. The findings provide insights into the additive‐induced inorganic‐rich interfacial layers for dendrite‐free SIBs. [ABSTRACT FROM AUTHOR]

Pt-based intermetallic compounds (IMCs) are considered as a class of promising fuel cell electrocatalysts, owing to their outstanding intrinsic activity and durability. However, the synthesis of uniformly dispersed IMCs with small sizes presents a formidable challenge during the essential high-temperature annealing process. Herein, a facile and generally applicable VO x matrix confinement strategy is demonstrated for the controllable synthesis of ordered L1 0 -PtM (M = Fe, Co, and Mn) nanoparticles, which not only enhances the dispersion of intermetallic nanocrystals, even at high loading (40 wt%), but also simplifies the oxide removal and acid-washing procedures. Taking intermetallic PtCo as an example, the as-prepared catalyst displays a high-performance oxygen reduction activity (mass activity of 1.52 A mg Pt -1 ) and excellent stability in the membrane electrode assemblies (MEAs) (the ECSA has just 7% decay after durability test). This strategy provides an economical and scalable route for the controlled synthesis of Pt-based intermetallic catalysts, which can pave a way for the commercialization of fuel cell technologies., (© 2024 Wiley‐VCH GmbH.)

Anion-reinforced solvation structure favors the formation of inorganic-rich robust electrode-electrolyte interface, which endows fast ion transport and high strength modulus to enable improved electrochemical performance. However, such a unique solvation structure inevitably injures the ionic conductivity of electrolytes and limits the fast-charging performance. Herein, a trade-off in tuning anion-reinforced solvation structure and high ionic conductivity is realized by the entropy-assisted hybrid ester-ether electrolyte. Anion-reinforced solvation sheath with more anions occupying the inner Na+ shell is constructed by introducing the weakly coordinated ether tetrahydrofuran into the commonly used ester-based electrolyte, which merits the accelerated desolvation energy and gradient inorganic-rich electrode-electrolyte interface. The improved ionic conductivity is attributed to the weakly diverse solvation structures induced by entropy effect. These enable the enhanced rate performance and cycling stability of Prussian blue||hard carbon full cells with high electrode mass loading. More importantly, the practical application of the designed electrolyte was further demonstrated by industry-level 18650 cylindrical cells., (© 2024 Wiley‐VCH GmbH.)

Multinary metal chalcogenides hold considerable promise for high-energy potassium storage due to their numerous redox reactions. However, challenges arise from issues such as volume expansion and sluggish kinetics. Here, a design featuring a layered ternary Bi 0.4 Sb 1.6 Te 3 anchored on graphene layers as a composite anode, where Bi atoms act as a lattice softening agent on Sb, is presented. Benefiting from the lattice arrangement in Bi 0.4 Sb 1.6 Te 3 and structure, Bi 0.4 Sb 1.6 Te 3 /graphene exhibits a mitigated expansion of 28% during the potassiation/depotassiation process and demonstrates facile K + ion transfer kinetics, enabling long-term durability of 500 cycles at various high rates. Operando synchrotron diffraction patterns and spectroscopies including in situ Raman, ex situ adsorption, and X-ray photoelectron reveal multiple conversion and alloying/dealloying reactions for potassium storage at the atomic level. In addition, both theoretical calculations and electrochemical examinations elucidate the K + migration pathways and indicate a reduction in energy barriers within Bi 0.4 Sb 1.6 Te 3 /graphene, thereby suggesting enhanced diffusion kinetics for K + . These findings provide insight in the design of durable high-energy multinary tellurides for potassium storage., (© 2024 Wiley‐VCH GmbH.)

Achieving reversible insertion/extraction in most cathodes for aqueous aluminum ion batteries (AAIBs) is a significant challenge due to the high charge density of Al 3+ 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 (Al 3+ /H 3 O + and ClO 4 - ) 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., (© 2024 Wiley‐VCH GmbH.)

The unsatisfactory oxygen evolution reaction (OER) activity of IrO 2 has intensively raised the cost and energy consumption of hydrogen generation from proton exchange membrane water electrolyzers. Here, the acidic OER activity of the rutile IrO 2 is significantly enhanced by the incorporation of trivalent metals (e.g., Gd, Nd, and Pr) to increase the Ir-O covalency, while the high-valence (pentavalent or higher) metal incorporation decreases the Ir-O covalency resulting in worse OER activity. Experimental and theoretical analyses indicate that enhanced Ir-O covalency activates lattice oxygen and triggers lattice oxygen-mediated mechanism to enhance OER kinetics, which is verified by the finding of a linear relationship between the natural logarithm of intrinsic activity and Ir-O covalency described by charge transfer energy. By regulating the Ir-O covalency, the obtained Gd-IrO 2-δ merely needs 260 mV of overpotential to reach 10 mA cm -2 and shows impressive stability during a 200-h test in 0.5 м H 2 SO 4 . This work provides an effective strategy for significantly enhancing the OER activity of the widely used IrO 2 electrocatalysts through the rational regulation of Ir-O covalency., (© 2023 Wiley‐VCH GmbH.)

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(ClO 4 ) 2 ·6H 2 O, ethylene glycol (EG), and InCl 3 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 H 2 O molecules are confined within the liquid eutectic network through dual-interaction, involving coordination with Zn 2+ 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., (© 2023 Wiley-VCH GmbH.)