Currently, development of suitable cathode materials for zinc‐ion batteries (ZIBs) is plagued by the sluggish kinetics of Zn2+ with multivalent charge in the host structure. Herein, it is ...demonstrated that interlayer Mn2+‐doped layered vanadium oxide (Mn0.15V2O5·nH2O) composites with narrowed direct bandgap manifest greatly boosted electrochemical performance as zinc‐ion battery cathodes. Specifically, the Mn0.15V2O5·nH2O electrode shows a high specific capacity of 367 mAh g−1 at a current density of 0.1 A g−1 as well as excellent retentive capacities of 153 and 122 mAh g−1 after 8000 cycles at high current densities up to 10 and 20 A g−1, respectively. Even at a low temperature of −20 °C, a reversible specific capacity of 100 mAh g−1 can be achieved at a current density of 2.0 A g−1 after 3000 cycles. The superior electrochemical performance originates from the synergistic effects between the layered nanostructures and interlayer doping of Mn2+ ions and water molecules, which can enhance the electrons/ions transport kinetics and structural stability during cycling. With the aid of various ex situ characterization technologies and density functional theory calculations, the zinc‐ion storage mechanism can be revealed, which provides fundamental guidelines for developing high‐performance cathodes for ZIBs.
Vanadium oxide pillared by interlayer doping of Mn2+ ions and water is synthesized through a facile microwave‐assisted strategy. When evaluated as a cathode for zinc‐ion batteries, the as‐prepared electrode delivers superior zinc‐ion storage properties in terms of high specific capacity, stable cycling capability, excellent rate, and low‐temperature performance.
Rechargeable zinc‐ion batteries (ZIBs) are emerging as a promising alternative for Li‐ion batteries. However, the developed cathodes suffer from sluggish Zn2+ diffusion kinetics, leading to poor rate ...capability and inadequate cycle life. Herein, an in situ polyaniline (PANI) intercalation strategy is developed to facilitate the Zn2+ (de)intercalation kinetics in V2O5. In this way, a remarkably enlarged interlayer distance (13.90 Å) can be constructed alternatively between the VO layers, offering expediting channels for facile Zn2+ diffusion. Importantly, the electrostatic interactions between the Zn2+ and the host O2−, which is another key factor in hindering the Zn2+ diffusion kinetics, can be effectively blocked by the unique π‐conjugated structure of PANI. As a result, the PANI‐intercalated V2O5 exhibits a stable and highly reversible electrochemical reaction during repetitive Zn2+ insertion and extraction, as demonstrated by in situ synchrotron X‐ray diffraction and Raman studies. Further first‐principles calculations clearly reveal a remarkably lowered binding energy between Zn2+ and host O2−, which explains the favorable kinetics in PANI‐intercalated V2O5. Benefitting from the above, the overall electrochemical performance of PANI‐intercalated V2O5 electrode is remarkable improved, exhibiting excellent high rate capability of 197.1 mAh g−1 at current density of 20 A g−1 with capacity retention of 97.6% over 2000 cycles.
An in situ polyaniline (PANI) intercalation strategy is developed to facilitate the Zn2+ (de)intercalation kinetics in V2O5. PANI not only expands the diffusion channels for facilitating Zn2+ diffusion, but also maintains the structural stability as interlayer pillars. Especially, its unique π‐conjugated structure, serving as electron‐reservoir, simultaneously shields the electrostatic interactions between Zn2+ and V2O5 host.
Rechargeable aqueous metal-ion batteries are very promising as alternative energy storage devices during the post-lithium-ion era because of their green and safe inherent features. Among the ...different aqueous metal-ion batteries, aqueous zinc-ion batteries (ZIBs) have recently been studied extensively due to their unique and outstanding benefits that hold promise for large-scale power storage systems. However, zinc anode problems in ZIBs, such as zinc dendrites and side reactions, severely shorten the ZIB's cycle lifetime, thus restricting their practical application. Here, we sum up in detail the recent progress on general strategies to suppress zinc dendrites and zinc anode side reactions based on advanced materials and structure design, including the modification of the planar zinc electrode surface layer, internal structural optimization of the zinc bulk electrode, modification of the electrolyte and construction of the multifunctional separator. The various functional materials, structures and battery efficiencies are discussed. Finally, the challenges for ZIBs are identified in the production of functional zinc anodes.
This review summarizes recent progresses in material and structural designs of zinc anodes for high-performance aqueous zinc-ion batteries.
Aqueous rechargeable Zn metal batteries have attracted widespread attention due to the intrinsic high volumetric capacity, low cost, and high safety. However, the low Coulombic efficiency and limited ...lifespan of Zn metal anodes resulting from uncontrollable growth of Zn dendrites impede their practical application. In this work, a 3D interconnected ZnF2 matrix is designed on the surface of Zn foil (Zn@ZnF2) through a simple and fast anodic growth method, serving as a multifunctional protective layer. The as‐fabricated Zn@ZnF2 electrode can not only redistribute the Zn2+ ion flux, but also reduce the desolvation active energy significantly, leading to stable and facile Zn deposition kinetics. The results reveal that the Zn@ZnF2 electrode can effectively inhibit dendrites growth, restrain the hydrogen evolution reactions, and endow excellent plating/stripping reversibility. Accordingly, the Zn@ZnF2 electrode exhibits a long cycle life of over 800 h at 1 mA cm−2 with a capacity of 1.0 mAh cm−2 in a symmetrical cell test, the feasibility of which is also convincing in Zn@ZnF2//MnO2 and Zn@ZnF2//V2O5 full batteries. Importantly, a hybrid zinc‐ion capacitor of the Zn@ZnF2//AC can work at an ultrahigh current density of ≈60 mA cm−2 for up to 5000 cycles with a high capacity retention of 92.8%.
A 3D interconnected ZnF2 matrix on the surface of Zn foil (Zn@ZnF2) is prepared through a simple and fast electrochemical anodic growth method. The as‐fabricated Zn@ZnF2 electrode can not only redistribute the Zn2+ ion flux, but also reduce the desolvation active energy significantly, leading to stable and facile Zn deposition kinetics.
Rechargeable zinc‐ion batteries (ZIBs) have recently attracted attention for applications in energy storage systems owing to their intrinsic safety, low cost, environmental compatibility, and ...competitive gravimetric energy density. To enable the practical applications of ZIBs, their energy density must be equivalent to the existing commercial lithium‐ion batteries. To acquire high‐energy density, increasing the operating voltage of the battery is undoubtedly an effective method, which demands cathode material to exhibit a high voltage versus Zn2+/Zn, while matching a highly reversible anode and an electrolyte with a sufficiently wide electrochemical stability window. This review focuses on the design strategies and challenges towards high‐voltage ZIBs. First, the basic electrochemistry of ZIBs and the recent progress in various high‐voltage cathode materials for ZIBs, including Prussian blue analogs, polyanionic compounds, and metal‐based oxides are introduced. The challenges and corresponding countermeasures of these materials are discussed, while strategies to further improve the cathode operating voltage, influence factors of voltage in the redox reaction, and energy storage mechanism are also illustrated. The following section describes the strategies towards high‐performance Zn anode, and summarizes the electrolytes that can help increase the battery voltage. The final section outlines the potential development in ZIBs.
This review focuses on the recent advancements of high‐voltage zinc‐ion batteries in aspects of cathode materials, Zn anodes, and electrolytes. Special attention is given to the challenges, design strategies, voltage variation trend of Prussian blue analogs, polyanionic compounds, and metal‐based oxides. Electrolytes with a wide electrochemical stability window, relevant challenges, and strategies on highly reversible Zn anodes are also reviewed.
Aqueous zinc-ion batteries (ZIBs), due to their sluggish Zn
2+
diffusion kinetics, continue to face challenges in terms of achieving superior high rate, long-term cycling and low-temperature ...properties. Herein, K
+
pre-intercalated layered V
2
O
5
(K
0.5
V
2
O
5
) composites with metallic features are capable of delivering excellent zinc storage performance. Specifically, the K
0.5
V
2
O
5
electrode delivers a high reversible capacity of 251 mA h g
−1
at 5 A g
−1
after 1000 cycles. Even at a low temperature of −20 °C, high reversible capacities of 241 and 115 mA h g
−1
can be obtained after 1000 cycles at 1 and 5 A g
−1
, respectively. The outstanding electrochemical performance is attributed to the incorporation of K
+
into the layered V
2
O
5
, which acts as pillars to promote the Zn
2+
diffusion and increase the structural stability during cycling. Density functional theory calculations demonstrate that the interlayer doping of K
+
can benefit electron migration, and therefore enhance the Zn
2+
(de)intercalation kinetics. Meanwhile, the Zn
2+
storage mechanism of K
0.5
V
2
O
5
is revealed by
ex situ
X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy and transmission electron microscopy characterization. This work may pave the way for exploiting high-performance cathodes for aqueous ZIBs.
Aqueous zinc-ion batteries (ZIBs), due to their sluggish Zn
2+
diffusion kinetics, continue to face challenges in terms of achieving superior high rate, long-term cycling and low-temperature properties.
Developing advanced high‐rate electrode materials has been a crucial aspect for next‐generation lithium ion batteries (LIBs). A conventional nanoarchitecturing strategy is suggested to improve the ...rate performance of materials but inevitably brings about compromise in volumetric energy density, cost, safety, and so on. Here, micro‐size Nb14W3O44 is synthesized as a durable high‐rate anode material based on a facile and scalable solution combustion method. Aberration‐corrected scanning transmission electron microscopy reveals the existence of open and interconnected tunnels in the highly crystalline Nb14W3O44, which ensures facile Li+ diffusion even within micro‐size particles. In situ high‐energy synchrotron XRD and XANES combined with Raman spectroscopy and computational simulations clearly reveal a single‐phase solid‐solution reaction with reversible cationic redox process occurring in the NWO framework due to the low‐barrier Li+ intercalation. Therefore, the micro‐size Nb14W3O44 exhibits durable and ultrahigh rate capability, i.e., ≈130 mAh g−1 at 10 C, after 4000 cycles. Most importantly, the micro‐size Nb14W3O44 anode proves its highest practical applicability by the fabrication of a full cell incorporating with a high‐safety LiFePO4 cathode. Such a battery shows a long calendar life of over 1000 cycles and an enhanced thermal stability, which is superior than the current commercial anodes such as Li4Ti5O12.
Micro‐size Nb14W3O44 with interconnected tunnel structure is synthesized by a facile solution combustion method. Li+ insertion/extraction in Nb14W3O44 is a single‐phase solid‐solution electrochemical mechanism, leading to high Li+ diffusion coefficient and excellent structural stability during cycling. The as‐prepared Nb14W3O44 exhibits ultrahigh‐rate and high‐safety Li+ storage performance.
With the constant focus on energy storage devices, layered materials are ideal electrodes for the new generation of highly efficient secondary ion batteries and supercapacitors due to their flexible ...2D structures and high theoretical capacities. However, the small interlayer distances in layered electrode materials and the strong Columbic interactions between the working ions and host lattice anions cause slow ion diffusion. In addition, structural collapse during repeated ion insertion and extraction reduces the cycling lifetime. As such, interlayer engineering strategies are effective approaches to optimize ion transmission kinetics and structural integrity. In view of the latest research on the interlayer engineering of layered materials, this review will discuss useful strategies to improve electrode performance. The synthetic strategies, characterization techniques, and effects of interlayer‐engineered layered materials, including metal oxides, metal sulfides, carbonous materials, and MXenes, are discussed in detail. The future outlook and challenges for interlayer engineering are also presented, which may pave the way for the development of new layered materials.
Interlayer engineering has emerged as a powerful approach for tailoring layered electrodes with flexible structures, tunable properties, and multiple active sites for secondary batteries and supercapacitors. This review highlights various tactics for interlayer engineering and explores their induced effects on electrochemical performance. Finally, the challenges and outlook for future work are also presented.
Environment‐friendly and low‐cost aqueous zinc‐ion batteries (ZIBs) have received considerable attention for large‐scale energy storage. However, the low coulombic efficiency and potential safety ...hazards of Zn‐metal anodes severely hinder their practical implementations. Herein, for the first time, mixed‐valence Cu2−xSe is proposed as a new intercalation anode to construct Zn‐metal‐free rocking‐chair ZIBs with a long lifespan. It is found that the introduction of low‐valence Cu not only modify active sites for Zn2+ ion storage, but also optimizes the electronic interaction between the active sites and the intercalated Zn2+ ion, leading to a favorable intercalation formation energy (−0.68 eV) and reduced diffusion barrier, as demonstrated by first‐principles calculation. Ex situ X‐ray diffraction, ex situ transmission electron microscopy and galvanostatic intermittent titration technique measurements reveal the reversible insertion/extraction of Zn2+ in Cu2−xSe via an intercalation reaction mechanism. Owing to the rigid host structure and facile Zn2+ diffusion kinetics, the Cu2−xSe nanorod anode shows an enhanced coulombic efficiency (above 99.5%), outstanding rate capability and excellent cycling stability. The as‐fabricated ZnxMnO2||Cu2−xSe Zn‐ion full battery exhibits an impressive electrochemical performance, particularly an ultralong cycle life of over 20 000 cycles at 2 A g−1. This study is expected to provide new opportunities for developing high‐performance rechargeable aqueous ZIBs.
Mixed‐valence Cu2−xSe is proposed as a new intercalation anode to construct Zn‐metal‐free rocking‐chair zinc‐ion batteries. The introduction of low‐valence Cu modifies active sites for Zn2+ ion storage and optimizes the electronic interaction between the active sites and intercalated Zn2+ ion, leading to an enhanced electronic conductivity and reduced diffusion barrier. The as‐fabricated ZnxMnO2||Cu2−xSe Zn‐ion full battery exhibits an impressive electrochemical performance, particularly an ultralong cycle life of over 20 000 cycles.
The increasingly stringent requirement in large‐scale energy storage necessitates the development of high‐performance sodium‐ion batteries (SIBs) that can operate under low‐temperature (LT) ...environment. Although SIBs can achieve good cycling stability and rate performance at room temperature, the sluggish electrochemical reaction kinetics at low temperature remains a great challenge for SIBs. Here, a superior LT SIB composed of 3D porous Na3V2(PO4)3/C (NVP/C‐F) and NaTi2(PO4)3/C foams (NTP/C‐F) is developed. First‐principles calculations reveal that the intrinsic Na+ diffusivity in NASICON‐type NVP and NTP is extremely high (maximum 3.84 × 10−5 for NVP and 2.94 × 10−9 cm2 s−1 for NTP) at –20 °C. In addition, the designed 3D interconnected porous foam structures demonstrate excellent electrolyte absorption ability and Na+ transport performance at low temperature. As a result, under −20 °C, the NVP/CF and NTP/CF electrodes (half‐cell configuration) can attain reversible capacities close to their theoretical values, and are able to be charged and discharged rapidly (20 C) for 1000 cycles. Based on these features, the designed NTP/CF||NVP/CF full cell also displays superb LT kinetics and cycling stability, making a great stride forward in the development of LT SIBs.
A high‐performance low‐temperature sodium ion full battery composed of 3D porous Na3V2(PO4)3/C and NaTi2(PO4)3/C foams is developed. Owing to the fast Na+ diffusivity of these two NASICON‐type electrodes and excellent electrolyte absorption ability of the foam structure, this full battery demonstrates superb kinetics and cycling stability (e.g., 20 C over 1000 cycles) at −20 °C.
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