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The cost‐effectiveness and environmentally friendly nature of aqueous zinc‐ion batteries (ZIBs) have garnered significant attention. Nevertheless, obstacles such as dendrite growth and side reactions have hindered their practical application. Here, an alkaline earth metal ion, strontium ions (Sr2+), is chosen as a dual‐functional electrolyte additive to improve the reversibility of ZIBs. Importantly, Sr2+ ions adsorb on the anode surface, creating a dynamic electrostatic shield layer, thus regulating the Zn2+ deposition behavior and suppressing side reactions. Meanwhile, Sr2+ ions prefer to adsorb on (002) and (110) planes of Zn, thus inducing the preferential deposition of (100) crystal plane and achieving dendrite‐free zinc anode. Consequently, the assembled Zn||Zn symmetric battery delivers an ultralong lifespan of 3500 h, and the Zn||Ti asymmetric battery shows a superior Coulombic efficiency of 99.8% for Zn stripping/plating at 2 mA cm−2. Further, the Zn||NH4V4O10 battery presents an excellent retention of 97.7% over 800 cycles under 2 A g−1. This research introduces a novel alkaline earth metal ion electrolyte additive and establishes its persistent dynamic electrostatic shielding effect and preferentially oriented (100) plane plating, ensuring dendrite‐free zinc deposition. These findings chart a course for further exploration of unexplored alkaline earth elements in enhancing metal battery technologies. [ABSTRACT FROM AUTHOR]

Single-walled carbon nanohorns (SWCNHs), which are sealed on one side with a conical cap and can self-aggregate, are aggregates with spherical morphology ranging from 30 to 100 nm and include dahlia, bud, and seed structures. These SWCNHs are suitable for electromagnetic wave absorption (EMWA) due to their conductivity loss. However, conductivity loss, which is part of three primary loss mechanisms, leads to SWCNHs suffering from impedance mismatching and a narrow effective absorption bandwidth (EAB). In this work, the content of vacancy-type defects in "dahlia-like" nitrogen-doped single-walled carbon nanohorns (NSWCNHs) is regulated by dielectric barrier discharge (DBD) plasma with argon to adjust their polarization and impedance matching. The high-energy argon ions from the plasma impact the bonds between the carbon atoms and adsorbed oxygen, leading to the sputtering of oxygen atoms from the surface and resulting in an increase in surface disorder and defect content. Vacancy-type defects improved polarization loss and optimized impedance matching, leading to the satisfactory EMWA performance of NSWCNHs. The NSWCNHs exhibit an outstanding minimum reflection loss (RLmin) of −57.94 dB when subjected to argon DBD treatment for 5 minutes, achieving this remarkable result at a thickness of 1.9 mm. Additionally, the effective absorption bandwidth (EAB) can cover 4.78 GHz after a treatment period of 1 minute. These results suggest that NSWCNHs have great potential as high-efficiency EMWA materials and demonstrate a new approach for designing high-performance EMWA absorbers. [ABSTRACT FROM AUTHOR]

Constructing artificial solid electrolyte interface on the Zn anode surface is recognized as an appealing method to inhibit zinc dendrites and side reactions, whereas the current techniques are complex and time‐consuming. Here, a robust and zincophilic zinc tungstate (ZnWO4) layer has been in situ constructed on the Zn anode surface (denoted as ZWO@Zn) by an ultrafast chemical solution reaction. Comprehensive characterizations and theoretical calculations demonstrate that the ZWO layer can effectively modulate the interfacial electric field distribution and promote the Zn2+ uniform diffusion, thus facilitating the uniform Zn2+ nucleation and suppressing zinc dendrites. Besides, ZWO layer can prevent direct contact between the Zn/water and increase the hydrogen evolution reaction overpotential to eliminate side reactions. Consequently, the in situ constructed ZWO layer facilitates remarkable reversibility in the ZWO@Zn||Ti battery, achieving an impressive Coulombic efficiency of 99.36 % under 1.0 mA cm−2, unprecedented cycling lifespan exceeding 1800 h under 1.0 mA cm−2 in ZWO@Zn||ZWO@Zn battery, and a steady and reliable operation of the overall ZWO@Zn||VS2 battery. The work provides a simple, low cost, and ultrafast pathway to crafting protective layers for driving advancements in aqueous zinc‐metal batteries. [ABSTRACT FROM AUTHOR]

The long‐term reversible plating/stripping of Zn metal anode is a critical aspect within aqueous zinc‐ion batteries (ZIBs). However, it is limited by uncontrolled electrodeposition and side reactions occurring at the anode/electrolyte interface. Guided by the metal‐coordination chemistry, a novel additive, sodium diphenylamine sulfonate (DASS), is added into ZnSO4 electrolyte to guide stably invertible zinc deposition. Theoretical calculations and experimental results reveal that the DASS can adsorbed on the Zn anode surface due to the strong double coordination effect between N, S sites and Zn (Zn─N, Zn─S), and this adsorbed DASS layer can not only prevent the intimate contact between H2O and anode to inhibit interfacial side reactions, but also guide the 3D Zn2+ion diffusion and uniform electrodeposition to inhibit zinc dendrites. Consequently, the DASS additive enables an ultra‐long stable cycling up to 2400 h at 1 mA cm−2 (1 mAh cm−2), even at an ultra‐high current density of 20 mA cm−2, a stable cycling of 250 h is demonstrated, highlighting the reliable coordination effect at the anode/electrolyte interface. This study offers a new perspective on the interfacial double‐coordination effect for achieving highly reversible Zn metal anodes in aqueous rechargeable zinc‐ion batteries. [ABSTRACT FROM AUTHOR]

The cost‐effectiveness and environmental benefits of aqueous zinc‐ion batteries (ZIBs) have attracted considerable attention. However, practical applications are hindered by side processes including dendritic growth and hydrogen evolution corrosion. Herein, gallium ions (Ga3+) have been chosen as a multifunctional electrolyte additive to improve the reversibility of zinc‐ion batteries (ZIBs). Remarkably, Ga3+ ions adhere to the anode surface, establishing a dynamic electrostatic shielding layer that modulates Zn2+ deposition and prevents side reactions. Typically, Ga3+ ions preferentially adsorb onto the (002) and (110) planes of Zn, facilitating preferential deposition on the (100) plane, resulting in a dendrites‐free zinc anode. Consequently, the Zn||Zn symmetrical cell with Ga3+‐modified electrolyte demonstrates a prolonged lifespan of 4000 h, while the Zn||Ti asymmetric cell exhibits an impressive coulombic efficiency of 99.12% for zinc stripping and plating at 2 mA cm−2. Additionally, the Zn||VO2 cell maintains high capacity retention after 1500 cycles at 5 A g−1. This work presents Ga3+ ions as an electrolyte additive, facilitating the development of a durable dynamic electrostatic shielding effect and preferential (100) plane electroplating, ensuring zinc deposition free from dendrite formation. Such discoveries form a basis for future investigations into novel materials to propel advancements in metal battery technology. [ABSTRACT FROM AUTHOR]

Despite the widespread adoption of Zn anodes for aqueous energy storage, the presence of an inherent passivation layer and the polycrystalline interface of commercial Zn foil consistently lead to non-uniform electrodeposition, undermining stability and practicality. Herein, the study introduces a chemically polished Zn metal anode (CP-Zn) fabricated via a simple immersion method. This "chemically polishing" process can effectively remove the interfacial passivation layer (de-passivation), providing ample active sites for plating/stripping and ensuring the uniformly distributed electric field and Zn 2+ ion flux. Additionally, selective etching during chemical polishing exposes more (002) crystal planes, promoting homogeneous and smooth zinc deposition while suppressing related side reactions. Demonstrated by CP-Zn anode, the symmetric cell exhibits stable cycling over 4600 h at 1 mA cm -2 and 240 h at 50% depth of discharge (DOD), with a CP-Zn||VO 2 full cell maintaining ≈75.3% capacity retention over 1000 cycles at 3 A g -1 . This chemically polishing strategy presents a promising avenue for advancing the commercialization of aqueous zinc-ion batteries., (© 2024 Wiley‐VCH GmbH.)

The use of vanadium(V)-based materials as electrode materials in electrochemical energy storage (EES) devices is promising due to their structural and chemical variety, abundance, and low cost. V-based materials with a layered structure and high multielectron transfer in the redox reaction have been actively explored for energy storage. Our current work presents the structural and electrochemical properties of a vanadium-based composite with TiO 2 @Ti 3 C 2 MXene, referred to as VM. This composite is obtained through the in situ thermal decomposition of the VO 2 (OH)/Ti 3 C 2 mixture, which is achieved by solution mixing and drying. The material structure is confirmed using various characterization tools, which establish an orthorhombic V 2 O 5 nanostructure compositing with nanocrystalline TiO 2 @Ti 3 C 2 . VM with 5 wt % MXene, referred to as VM5, can achieve 460 mAhg -1 at a current density of 0.1 Ag 1- and 290 mAhg -1 at 1 Ag 1- , with an average coulombic efficiency of 98.5%. The presence of the V 2 O 5 /TiO 2 (nanocrystals) heterojunction attached with Ti 3 C 2 sheets contributed to reduced charge transfer resistance. The cyclic stability shows a capacity retention of 62% over 500 cycles at 1 Ag 1- (4C rate, where 1C equals 0.25 Ag 1- ) with a 0.22 capacity drop with each cycle. Dunn's approach to examining the charge storage mechanism demonstrates 72% contribution of the surface-dominant capacitive process and 28% of the diffusion-controlled intercalation process at 0.4 mVs -1 , suggesting a potential high-performance pseudocapacitive hybrid electrode material for lithium-ion batteries.

Constructing artificial solid electrolyte interface on the Zn anode surface is recognized as an appealing method to inhibit zinc dendrites and side reactions, whereas the current techniques are complex and time-consuming. Here, a robust and zincophilic zinc tungstate (ZnWO 4 ) layer has been in situ constructed on the Zn anode surface (denoted as ZWO@Zn) by an ultrafast chemical solution reaction. Comprehensive characterizations and theoretical calculations demonstrate that the ZWO layer can effectively modulate the interfacial electric field distribution and promote the Zn 2+ uniform diffusion, thus facilitating the uniform Zn 2+ nucleation and suppressing zinc dendrites. Besides, ZWO layer can prevent direct contact between the Zn/water and increase the hydrogen evolution reaction overpotential to eliminate side reactions. Consequently, the in situ constructed ZWO layer facilitates remarkable reversibility in the ZWO@Zn||Ti battery, achieving an impressive Coulombic efficiency of 99.36 % under 1.0 mA cm -2 , unprecedented cycling lifespan exceeding 1800 h under 1.0 mA cm -2 in ZWO@Zn||ZWO@Zn battery, and a steady and reliable operation of the overall ZWO@Zn||VS 2 battery. The work provides a simple, low cost, and ultrafast pathway to crafting protective layers for driving advancements in aqueous zinc-metal batteries., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Single-walled carbon nanohorns (SWCNHs), which are sealed on one side with a conical cap and can self-aggregate, are aggregates with spherical morphology ranging from 30 to 100 nm and include dahlia, bud, and seed structures. These SWCNHs are suitable for electromagnetic wave absorption (EMWA) due to their conductivity loss. However, conductivity loss, which is part of three primary loss mechanisms, leads to SWCNHs suffering from impedance mismatching and a narrow effective absorption bandwidth (EAB). In this work, the content of vacancy-type defects in "dahlia-like" nitrogen-doped single-walled carbon nanohorns (NSWCNHs) is regulated by dielectric barrier discharge (DBD) plasma with argon to adjust their polarization and impedance matching. The high-energy argon ions from the plasma impact the bonds between the carbon atoms and adsorbed oxygen, leading to the sputtering of oxygen atoms from the surface and resulting in an increase in surface disorder and defect content. Vacancy-type defects improved polarization loss and optimized impedance matching, leading to the satisfactory EMWA performance of NSWCNHs. The NSWCNHs exhibit an outstanding minimum reflection loss (RL min ) of -57.94 dB when subjected to argon DBD treatment for 5 minutes, achieving this remarkable result at a thickness of 1.9 mm. Additionally, the effective absorption bandwidth (EAB) can cover 4.78 GHz after a treatment period of 1 minute. These results suggest that NSWCNHs have great potential as high-efficiency EMWA materials and demonstrate a new approach for designing high-performance EMWA absorbers.