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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]

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]

Aqueous zinc‐ion batteries (AZIBs) are highly promising for grid‐scale energy storage due to their high‐safety and low‐cost characteristics. Nevertheless, the progress in AZIBs has been impeded due to challenges encompassing corrosion, hydrogen evolution reaction, and the formation of dendrites on Zn anodes. These issues arise from the decomposition of active water molecules in the Zn2+ solvation structure in the electrolyte. Various strategies have been proposed to regulate the electrode/electrolyte interface to effectively address these problems. In spite of remarkable headway, an inadequacy of comprehensive studies addressing the mechanisms and evolutionary dynamics of the electrode/electrolyte interface is evident within scientific literature. This overview aims to provide a comprehensive overview of the strategies for regulating the electrode/electrolyte interface, focusing on dendrite‐free and side reactions‐suppressed AZIBs. These strategies include the introduction of metal ion additives, inorganic additives, surfactant additives, polymer additives and organic additives. Furthermore, a detailed examination is made on the effects and underlying mechanisms associated with modifying the electrolyte at the interface between the electrode and electrolyte. Moreover, an appraisal is provided on the performance metrics of diverse strategies and prospective research directions are recommended as well. [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 low cost and intrinsic safety of rechargeable aqueous zinc‐ion batteries (ZIBs) contribute to their significant potential in grid‐level energy storage systems. However, the limited cathode options still hinder the development of ZIBs, which always delivers poor rate capacities and cycling stability. Herein, Monoclinic phase H3.78V6O13 microspheres with a stable internal framework and intrinsic metallic properties as a high‐performance cathode for ZIBs are proposed and utilized. The reversible Zn2+insertion/de‐insertion mechanism in H3.78V6O13through ex situ X‐ray diffraction, X‐ray absorption near‐edge structure, and in situ Raman involves the enlargement/shrink of interplanar distance, the decrease/increase of the V valance, and the open/recombine of V─O/V─V bonds. Further, experiments and theoretical calculations elucidate the superior electrochemical performance and extraordinary reaction kinetics in H3.78V6O13. The as‐prepared H3.78V6O13 cathode delivers high specific capacity of 406 mAh g–1 at 0.1 A g–1, excellent structure stability with 100% manifested after 120 cycles at 0.5 A g–1, 72.9% retained after 15 000 cycles at 10 A g–1. This research offers distinctive perspectives on the development of high‐performance cathode materials for ZIBs and enhances the understanding of the electrochemical reaction mechanisms of vanadium oxides. [ABSTRACT FROM AUTHOR]

Fast and continuous ion insertion is blocked in the common electrodes operating with widely accepted single‐ion storage mechanism, primarily due to Coulomb repulsion between the same ions. It results in an irreconcilable conflict between capacity and rate performance. Herein, we designed a porous organic framework with novel multiple‐ion co‐storage modes, including PF6−/Li+, OTF−/Mg2+, and OTF−/Zn2+ co‐storage. The Coulomb interactions between cationic and anionic carriers in the framework can significantly promote electrode kinetics, by rejuvenating fast ion carrier migration toward framework interior. Consequently, the framework via PF6−/Li+ co‐storage mode shows a high energy density of 878 Wh kg−1 cycled more than 20 000 cycles, with an excellent power density of 28 kW kg−1 that is already comparable to commercial supercapacitors. The both greatly improved energy and power densities via the co‐storage mode may pave a way for exploring new electrodes that are not available from common single‐ion electrodes. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) transition metal dichalcogenides (TMDs), a rising star in the post‐graphene era, are fundamentally and technologically intriguing for photocatalysis. Their extraordinary electronic, optical, and chemical properties endow them as promising materials for effectively harvesting light and catalyzing the redox reaction in photocatalysis. Here, we present a tutorial‐style review of the field of 2D TMDs for photocatalysis to educate researchers (especially the new‐comers), which begins with a brief introduction of the fundamentals of 2D TMDs and photocatalysis along with the synthesis of this type of material, then look deeply into the merits of 2D TMDs as co‐catalysts and active photocatalysts, followed by an overview of the challenges and corresponding strategies of 2D TMDs for photocatalysis, and finally look ahead this topic. [ABSTRACT FROM AUTHOR]

MXene‐based materials with excellent conductivity and stability features have attracted worldwide attention as anode of lithium‐ion batteries (LIBs), while the serious stacking issue and low capacity still hinder its further development in the field of energy storage. In this work, a nanohybrid architecture (Nb‐TiO2−x/MXene) is prepared with Nb‐TiO2−x particles conformally coated on the (Ti0.9Nb0.1)3C2Tx MXene via a facile annealing method, which delivers a high specific capacity of 279.2 mAh g−1 at the current density of 0.1 A g−1 and a superior capacity retention of 91.5% after 2000 cycle at 1 A g−1 as the anode material of LIBs. Importantly, the (Ti0.9Nb0.1)3C2Tx MXene layers provide sufficient active sites and open pathways as well as structural support for the reversible Li+ insertion/extraction, and the Nb‐TiO2−x particles enable reversible and fast Li+ diffusion and storage, thus leading to high‐performance and durable anode materials. This work offers a guidance for the elaborate design of MXene‐based nanostructured electrodes toward advanced energy storage devices. [ABSTRACT FROM AUTHOR]

The dendrite issues associated with zinc anode lead to safety hazards and sluggish reaction kinetics, and largely restrain widespread application of aqueous zinc ion batteries (ZIBs). Herein, a functional separator composed of cellulose nanofibers and graphene oxide (CG) is developed for dendrite‐free and exceptionally stable ZIBs, realized by uniform hexagonal zinc deposits with manipulated crystallographic orientation (002) plane. This CG separator with negative surface charges and abundant zincophilic‐O groups ensures the strong interaction between the separator and zinc species, simultaneously inducing Zn(002) deposition due to the low mismatch between (002)Zn and (002)GO, thus initiating the preferential orientation of the zinc growth along the horizontal direction due to strong Zn binding ability, and uniform interfacial charge of Zn(002) deposition. Furthermore, the CG separator can effectively promote the uniform nucleation of Zn2+ and eliminate side effects. Accordingly, extremely low polarization of 58 mV at 0.5 mA cm−2, and ultralong cycle life over 1750 h at 2 mA cm−2 and 400 h at 20 mA cm−2 are achieved for the zinc anode. Notably, the CG separator significantly boosts rate capability and cyclability of coin‐type full batteries (Zn||Zn(CF3SO3)2||V2O5, Zn||ZnSO4+MnSO4||MnO2/graphite) and a flexible soft‐packaged battery (Zn||MnO2). Therefore, this work introduces a sustainability consideration in to the design of separators for constructing dendrite‐free ZIBs. [ABSTRACT FROM AUTHOR]

Manganese‐based materials are considered potential cathode materials for aqueous zinc ion batteries (ZIBs). However, the dissolution of manganese leading to an abrupt decline of capacity and the sluggish electrochemical reaction kinetics are still the main bottlenecks restricting their further development. Herein, a NiMn‐layered double hydroxide‐derived Ni‐doped Mn2O3 (NM) is developed to suppress the dissolution of manganese. The incorporation of Ni2+ can promote electronic rearrangement and enhance the conductivity, ultimately improving the reaction kinetics and electrochemical performance of the NM. Moreover, the doped Ni2+ can effectively stabilize the MnO bond of Mn2O3 by reducing the formation energy. In addition, the storage mechanism based on the simultaneous insertion and transformation of H+ and Zn2+ is demonstrated. Interestingly, the Ni‐doped Mn2O3 shows a high specific capacity of 252 mAh g–1 (0.1 A g–1), three times more than the pure Mn2O3 (72 mAh g–1). The capacity retention (≈85.6% over 2500 cycles at 1.0 A g–1) is also more excellent when comparing with the Mn2O3 cathode (≈49.7%). Significantly, an ultra‐high energy density of 327.6 Wh kg–1 has been achieved using Ni‐doped Mn2O3 cathode, which suggests that the synergistic effect of manganese and other transition metal ions provide a promising strategy for future development of ZIBs. [ABSTRACT FROM AUTHOR]

A new SiCx/TiCx electrode material has been synthesized by ball‐milling of Ti3SiC2 MAX phase. To demonstrate the possible applications for lithium‐ion batteries, the electrochemical properties of the SiCx/TiCx nanocomposite was studied. The results indicate that this new material has a higher specific capacity (170 mAh/g) than those of pure SiC (93 mAh/g), TiC (75 mAh/g), and the mixture of SiC‐TiC (122 mAh/g) at current density of 100 mA/g for 300 cycles. Furthermore, the SiCx/TiCx nanocomposite has a specific capacity of 110 mAh/g, better than those of artificial graphite (labeled: SAG−R, 26 mAh/g) and mesocarbon microbeads (labeled: MCMB, 21 mAh/g), at current density of 1 A/g for 1000 cycles. The enhancement mechanism of the SiCx/TiCx nanostructure has been discussed by the DFT calculation. Further development of this anode material may enable practical applications for long cycling and fast charge‐discharge anode in rechargeable batteries. [ABSTRACT FROM AUTHOR]

The construction of a 2D–2D heterostructured composite is an efficient method to improve the photocatalytic hydrogen generation capability under visible light. In this work, simple heat treatment of a mixture of g‐C3N4 and delaminated Ti3C2 was used to prepare a series of d‐Ti3C2/TiO2/g‐C3N4 nanocomposites. The d‐Ti3C2 not only acted as the support layer and resource to glue the anatase TiO2 particles and g‐C3N4 layers together but also served as the fast electron transfer channel to improve the photogenerated charge carriers' separation efficiency. By tuning the g‐C3N4/d‐Ti3C2 mass ratio, heating temperature and soaking time, the d‐Ti3C2/TiO2/g‐C3N4 nanocomposite 4‐1‐350‐1 achieved an excellent H2 evolution rate of 1.62 mmol h−1 g−1 driven by a 300 W Xe lamp with a 420 nm cutoff filter. The heterostructured composite photocatalyst was stable even after 3 cycles, representing excellent potential for the practical application in solar energy conversion. Heterostructured d‐Ti3C2/TiO2/g‐C3N4! The photocatalytic activities of Ti3C2 and g‐C3N4 are critically dependent on the microstructure. A facile heating treatment of the Ti3C2 and g‐C3N4 mixture is used to obtain heterostructured d‐Ti3C2/TiO2/g‐C3N4 nanocomposites (see image). The TiO2 particles and g‐C3N4 nanosheets are glued together by the delaminated Ti3C2 layers, demonstrating excellent performance in visible‐light photocatalytic H2 evolution. [ABSTRACT FROM AUTHOR]

Semiconductor photocatalysis is regarded as an ideal method for use in solving the energy shortage and environmental issues by converting solar energy to chemical energy. Herein, we have designed a facile synthetic methodology to obtain a ternary co‐modified g‐C3N4 composite via WS2 and carbon‐doped TiO2 (C‐TiO2) nanorods with highly efficient photocatalytic activity for hydrogen production from deionized (DI) water and a natural seawater system under visible‐light illumination. This composite exhibits enhanced photocatalytic activity compared to the pristine g‐C3N4, WS2, C‐TiO2 nanorods, and the reference‐modified g‐C3N4 composite with individual WS2 or C‐TiO2 nanorods. Co‐modified g‐C3N4 composite shows a great photostability in both DI water and seawater. Under λ=420 nm monochromatic light illumination, the apparent quantum efficiency of the co‐modified g‐C3N4 composite in seawater solution is 13.08 %, which is higher than pure g‐C3N4 (5.06 %). WS2, TiO2, and g‐C3N4 constitute a ternary heterojunction boosting the fast separation of photoinduced electron–hole pairs, which plays a crucial role in enhancing photocatalytic activity. Therefore, the WS2 and C‐TiO2 nanorod co‐modified g‐C3N4 composite with high photocatalytic performance provides a promising candidate for rationally utilizing the seawater resource to produce clean chemical energy. A ternary co‐modified g‐C3N4 composite with WS2 and C‐TiO2 nanorods has been designed and synthesized to split seawater to give clean hydrogen energy. WS2 and C‐TiO2 nanorods act as effective charge separators, resulting in the enhanced photocatalytic performance on co‐modified g‐C3N4 compared with pristine g‐C3N4 and the individual modified g‐C3N4 with WS2 or C‐TiO2 (see figure). [ABSTRACT FROM AUTHOR]

Ni-diamond composite coatings with high concentration and uniform distribution of diamond particles were prepared by using sediment co-deposition (SCD) technique from Watts-type electrolyte without any additives. The surface and cross-section morphology was evaluated by optical microscope (OM) and scanning electron microscopy (SEM). It was demonstrated that the Ni-monolayer diamond composite coatings ~40 ± 5 µm was successfully prepared by the new developed setup for SCD technique. Using this new developed setup, high concentration and uniform distribution of diamond particles of Ni-monolayer diamond composite coatings were easily fabricated. The wear resistance and cutting performance of obtained composite coatings were also investigated. The results revealed that anti-wear and cutting performance is superior to those prepared via conventional co-electrodeposition (CED) technique and pure Ni coatings. In the SCD process, with the increasing diamond content, the wear resistance is approximately the same, and the cutting performance decreases. Therefore, not only the diamond particle content is responsible for the wear resistance and cutting performance, the distribution of diamond particles is also very important factor. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

First-principles density functional calculations are employed to provide a fundamental understanding of the structural features, mechanical properties, deformation behaviours and its electronic origin for the new synthesized FeB4. The calculated elastic moduli suggest that FeB4 has a low compressibility, but results of ideal shear strength and theoretical hardness indicate that FeB4 is a hard material, not a superhard material. We find that the collapse of the unique corrugated B6 units ring in FeB4 under deformation is responsible for the failure under tensile and shear deformation based on the calculated charge density distribution and bonding evolution. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [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]