Cathode Materials For Zinc-ion Batteries Research Articles

Tailored thickness engineering of Bi2Se3 nanosheets for superior cathodic performance in aqueous zinc-ion batteries

Bi2Se3 is considered a suitable cathode material for zinc-ion batteries (ZIBs) because of its high conductivity and large layer spacing. Herein, Bi2Se3 nanosheets with varying thicknesses are successfully synthesized using a one-step solvothermal process with adding different amounts of ethylenediamine. The introduction of ethylenediamine reduces the thickness of Bi2Se3 from 250 nm to 22.7 nm. The thin structure exposes more active sites and shortens ion transport paths. Therefore, the optimized Bi2Se3 nanosheet exhibits outstanding specific capacity (410 mA h g−1 at 0.2 A/g), high-rate performance (230 mA h g−1 at 5 A/g), and remarkable cycling stability (82.3 % capacity retention after 1200 cycles at 5 A/g). Furthermore, an in-depth exploration of cathodes during cycling is conducted to investigate the charge/discharge mechanism. A dynamic phase transition from Bi2Se3 to BiSe, accompanied by nanosheet exfoliation, is observed during the initial few cycles, designating BiSe as the primary active material. Moreover, an additional redox reaction involving multiple electrons has been proposed. This study offers a valuable guidance for utilizing Bi2Se3 as a cathode in ZIBs.

A Pyrophosphate Bifunctional Cathode with Inductive Effect for High-Voltage and Self-Charging Zinc Ion Battery.

With the growing demand for new energy storage devices, rechargeable aqueous zinc ion batteries (ZIBs) have attracted widespread attention due to their low cost and high safety. Among the cathode materials for ZIBs, polyanionic-based cathode materials with high voltage, high stability, and low cost have great potential. In this paper, tetragonal Na2VOP2O7 was prepared using a simple sol-gel method. The discharge platform voltage amounted to 1.8 V and had good rate and cycle performance due to the inductive effect of pyrophosphate. Then, a protective layer of Zn-hydroxyapatite (ZnHAP) modification was applied to the cathode surface, which can inhibit the hydrolysis of vanadium ions. The capacity was enhanced by 19 % after modification and the capacity retention after 100 cycles was also higher. Interestingly, the Na2VOP2O7 cathode also possesses a self-charging effect, recovering to 48 % of its initial capacity with an open-circuit voltage (OCV) of 1.1 V within a certain period, and light exposure can reduce the self-charging time by 83 %. These beneficial results indicate that the pyrophosphate bifunctional cathode with inductive effect has a great potential to construct high-voltage and multifunctional zinc ion battery.

MoS2/ReS2 Hollow Heterojunction for Enhanced Aqueous Zinc-Ion Storage Performance.

The research of cathode materials for water-based zinc ion batteries (ZIBs) is very hot because the current mainstream electrode makes it difficult to meet the requirements of high specific discharge capacity and maintain a stable structure in the electrochemical process. In this work, the cathode properties are adjusted by the modification idea of morphology regulation and heterojunction construction. The simple hydrothermal method is used to prepare the hollow bimetallic heterojunction nanospheres, and their electrochemical properties as cathode materials for ZIBs are studied for the first time. Herein, the optimized cathode delivers high-rate performance and long-term cycling stability (∼98.9% Coulombic efficiency at 0.1 A g-1 after 200 cycles). The results indicate that the hollow bimetallic heterojunction nanospheres can support the material structure and provide a wide Zn2+ migration channel. The excellent performance is because hollow heterojunction bimetallic sulfides can provide abundant catalytic active sites, improve the mobility of electrons, and enhance the battery performance fundamentally. Therefore, we firmly believe that the combination of the different modification ideas can coordinate to adjust the electrode performance of ZIBs, enriching the electrode types and expanding the energy system application range.

Designing MnO2@amorphous carbon core-shell structure as a cathode to enhance rate performance and cycling stability of aqueous zinc-ion batteries

Manganese dioxide has received significant attention as a prospective cathode material in aqueous zinc-ion batteries (ZIBs) owing to its elevated working voltage and commendable energy density. Nevertheless, challenges such as structural instability, manganese dissolution, and poor electrical conductivity remain significant barriers to the practical application of research. Here, the MnO2 nanorods encapsulated in the amorphous carbon (MnO2@C) with core-shell structure are prepared by a special hard template method, and investigated as cathode materials for ZIBs. The amorphous carbon, characterized by its structural defects and disorder, manifests heightened active site density, thereby establishing an efficient conduit for charge transport. Concurrently, the nano-dimensional interstitial spaces augment the active sites available for zinc insertion reactions, thereby effectively curtailing the ion diffusion path and, consequently, engendering heightened electrochemical performance. Moreover, the distinctive core-shell architecture of MnO2@C not only furnishes substantial spatial accommodation but also serves to alleviate volume alterations throughout charge and discharge events. Consequently, MnO2@C demonstrates outstanding electrochemical performance, with reversible capacities of 210 mAh·g−1 and 50 mAh·g−1 at 0.1 A·g−1 and 1.6 A·g−1, respectively. Furthermore, even after 600 cycles at 0.8 A·g−1, it maintains exceptional cycling performance, reaching 102 mAh·g−1, endowing MnO2@C cathodes with robust competitiveness in aqueous ZIBs.

Solvothermal Guided V2O5 Microspherical Nanoparticles Constructing High-Performance Aqueous Zinc-Ion Batteries.

Rechargeable aqueous zinc-ion batteries have attracted a lot of attention owing to their cost effectiveness and plentiful resources, but less research has been conducted on the aspect of high volumetric energy density, which is crucial to the space available for the batteries in practical applications. In this work, highly crystalline V2O5 microspheres were self-assembled from one-dimensional V2O5 nanorod structures by a template-free solvothermal method, which were used as cathode materials for zinc-ion batteries with high performance, enabling fast ion transport, outstanding cycle stability and excellent rate capability, as well as a significant increase in tap density. Specifically, the V2O5 microspheres achieve a reversible specific capacity of 414.7 mAh g-1 at 0.1 A g-1, and show a long-term cycling stability retaining 76.5% after 3000 cycles at 2 A g-1. This work provides an efficient route for the synthesis of three-dimensional materials with stable structures, excellent electrochemical performance and high tap density.

K-ion preintercalated MnO2 nanorods as a high-rate cathode material for aqueous zinc-ion batteries

The integration of Zn/α-MnO2 in aqueous zinc-ion batteries (ZIBs) has emerged as a promising avenue owing to their eco-friendliness, facile manufacturability, cost-effectiveness, low flammability, and commendable electrochemical performance. However, the intrinsic limitation in the rate capability of α-MnO2 constitutes a significant impediment to its practical application. In this study, we introduce K-ion preintercalated nanorods (K-MnO2-NR) with a diameter of approximately 10 nm as a cathode material for ZIBs. The synthesis of K-MnO2-NR entails a facile one-step electrochemical participation method, whereby K-ion are electrochemically intercalated into the tunnel-structured α-MnO2. The incorporation of K-ion serves a dual purpose of enhancing the electrical conductivity of manganese oxides and stabilizing the tunnel structure. Consequently, K-MnO2-NR manifests exceptional rate capability, exhibiting a specific capacity of 222 mAh g−1 at 2 A g−1, coupled with outstanding cycling stability (with negligible capacity decay observed over 1450 cycles at 2 A g−1). The facile and scalable synthesis process underscores its potential for large-scale production and eventual commercialization in pouch cells for energy storage applications.

Metal ions and organic molecule co-intercalated vanadium oxide cathode for high-performance zinc-ion batteries

Vanadium oxide is a highly promising cathode material for zinc-ion batteries due to its unique layered structure and high theoretical capacity. However, the material dissolution and structural collapse severely limit the development of zinc-ion batteries. Herein, inorganic metal ions (Mg2+) and organic polymer molecules (PANI) were introduced into the hydrated vanadium oxide interlayer in this paper. Mg2+ ions enhance the conductivity of the cathode and widen the interlayer spacing. Meanwhile, PANI serves to cushion the structural expansion resulting from ion embedding and stabilize the layered structure. Additionally, PANI actively participates in the charging and discharging process, thereby enhancing the diffusion rate of Zn2+. Thanks to the synergistic effect of Mg2+ and PANI, the MgVOH/PANI cathode exhibits a discharge capacity of 412 mAh·g−1 at 0.1 A g−1 and retains 93% of its capacity after 1000 cycles at a current density of 2A·g−1. This synergistic strategy of combining organic molecules and inorganic ions can provide a reference for improving the kinetic and structural stability of other aqueous battery cathodes.

2D Conductive Metal-Organic Frameworks Based on Tetraoxa[8]circulenes as Promising Cathode for Aqueous Zinc Ion Batteries.

Aqueous zinc-ion batteries (ZIBs) are the new generation electrochemical energy storage systems. Recently, two-dimensional conductive metal-organic frameworks (2D c-MOFs) are attractive to serve as cathode materials of ZIBs due to their compositional diversity, abundant active sites, and excellent conductivity. Despite the growing interest in 2D c-MOFs, their application prospects are still to be explored. Herein, a tetraoxa[8]circulene (TOC) derivative with unique electronic structure and interesting redox-active property are synthesized to construct c-MOFs. A series of novel 2D c-MOFs (Cu-TOC, Zn-TOC and Mn-TOC) with different conductivities and packing modes are obtained by combining the linker tetraoxa[8]circulenes-2,3,5,6,8,9,11,12-octaol (8OH-TOC) and corresponding metal ions. Three c-MOFs all exhibit typical semiconducting properties, and Cu-TOC exhibits the highest electrical conductivity of 0.2 S cm-1 among them. Furthermore, their electrochemical performance as cathode materials for ZIBs have been investigated. They all performed high reversible capacity, decent cycle stability and excellent rate capability. This work reveals the key insights into the electrochemical application potential of 2D c-MOFs and advances their development as cathode materials in ZIBs.

Recent development of manganese dioxide-based materials as zinc-ion battery cathode.

The development of advanced cathode materials for zinc-ion batteries (ZIBs) is a critical step in building large-scale green energy conversion and storage systems in the future. Manganese dioxide is one of the most well-studied cathode materials for zinc-ion batteries due to its wide range of crystal forms, cost-effectiveness, and well-established synthesis processes. This review describes the recent research progress of manganese dioxide-based ZIBs, and the reaction mechanism, electrochemical performance, and challenges of manganese dioxide-based ZIBs materials are systematically introduced. Optimization strategies for high-performance manganese dioxide-based materials for ZIBs with different crystal forms, nanostructures, morphologies, and compositions are discussed. Finally, the current challenges and future research directions of manganese dioxide-based cathodes in ZIBs are envisaged.

Ultra-low diffusion barrier tetramethyl ammonium cation-intercalated layered MnO2 for high-performance aqueous zinc-ion batteries

TMA+ pre-intercalated MnO2 displays enhanced diffusion kinetics, high capacity, and robust cycling stability as a cathode material for zinc-ion batteries.

The importance of electrolyte environment during in situ self-transformation for synthesizing V2O5·nH2O.

V2O5·nH2O is a promising cathode material for zinc-ion batteries. One of the synthesis methods of V2O5·nH2O is in situ self-transformation. In this communication, we focus on the influence of the electrolyte environment during in situ self-transformation (from VO2 to V2O5·nH2O). 2 M ZnSO4 and 2 M Zn(OTf)2 were used as different electrolytes to produce VOH-1 and VOH-2. VOH-1 expands in volume along the electric field to form a porous surface structure and shows low crystallinity along the (0 0 1) plane, while VOH-2 exhibits the opposite. These advantages enable the assembled batteries with VOH-1 to maintain excellent cycling performance at a rate of 2 A g-1 with a capacity of 500 mA h g-1 and stable cycling for 1800 cycles.

Cobalt-doped manganese(iii) oxide cathode materials with enhanced electrochemical performance for aqueous zinc-ion batteries

Co–Mn2O3 is prepared via a CoMn glycerate derivatization method as a cathode material for zinc-ion batteries, exhibiting enhanced diffusion kinetics, high capacity, and excellent cycling stability.

Manganese-based MOF interconnected carbon nanotubes as a high-performance cathode for rechargeable aqueous zinc-ion batteries

Aqueous zinc-ion batteries (ZIBs) have attracted extensive attention due to their low cost, environmental friendliness, and high volumetric specific capacity. However, the design of cathode materials with high performance for ZIBs is quite limited. In this paper, a kind of manganese-based metal-organic framework/carbon nanotubes (Mn-MOF/CNT) composite is prepared as the cathode material for ZIBs via a one-pot in situ solvothermal method. Particularly, the assembled Mn-MOF/CNT//Zn battery exhibits high specific capacity (260 mAh g−1 at 50 mA g−1) and excellent capacity retention (approximately 100 %) after 900 cycles at 1000 mA g−1. This significant electrochemical performance is attributed to the high porosity and the high conductivity of Mn-MOF/CNT, as well as the Mn2+ electrolyte additive. This work renders a new sight to design high-performance MOF-based cathode materials for aqueous ZIBs.

Constructing stable V2O5/V6O13 heterostructure interface with fast Zn2+ diffusion kinetics for ultralong lifespan zinc‐ion batteries

Given their plentiful reserves, impressive safety features, and economical pricing, aqueous zinc − ion batteries (ZIBs) have positioned themselves as strong competitors to lithium − ion batteries. Yet, the scarcity of available cathode materials poses a challenge to their continued development. In this study, a V2O5/V6O13 heterostructure has been synthesized using a one − pot hydrothermal approach and employed as the cathode material for ZIBs. As evidenced by both experimental and theoretical findings, V2O5/V6O13 heterostructure delivers a rapid electrons and ions diffusion kinetics promoted by the stable interface and strong electronic coupling with significant charge transfer between V2O5 and V6O13, as well as a stable interface achieved by adjusting V − O bond length. Consequently, the optimized V2O5/V6O13 heterostructure cathode of ZIBs demonstrates exceptional capacity (338 mAh g−1 at 0.1 A g−1), remarkable cycling stability (92.96 % retained after 1400 cycles at 1 A g−1). Through comprehensive theoretical calculations and ex situ characterization, the kinetic analysis and storage mechanism of Zn2+ are thoroughly investigated, providing a solid theoretical foundation for the advancement of novel V − based cathode materials aimed at enhancing the performance of ZIBs.

In-situ polymerization of polypyrrole on Prussian blue analogue for high capacity and flexible zinc-ion batteries

Prussian blue analogues (PBAs) have been considered as promising cathode materials for zinc-ion batteries. However, severe capacity decay issues hamper their deployment. Herein, Mn-ion-substituted zinc hexacyanoferrate (MZHCF) cathode materials were coated with polypyrrole (PPy) by in situ polymerization. The prepared MZHCF@PPy composites have exhibited significant ionic absorption affinity and great structural stability. Benefiting from the PPy coating, the ZIBs based on MZHCF@PPy cathodes and a conductive poly(acrylamide) (PAAM) hydrogel electrode exhibit enhanced capacities, which reach a maximum value of 190.1 mAh g−1 at 0.5 A g−1, three times higher than that of the device based on MZHCF electrodes. The flexible ZIBs not only present outstanding cyclic performance but also retain stable energy storage capability under various deformations. The presented method is a promising technology for the practical application of rechargeable ZIBs with high safety and flexibility.

Unveiling the X‐Ray Absorption Chemistry of H3.78V6O13 Cathode for Aqueous Zinc‐Ion Batteries

AbstractThe 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.

De/Protonation Associated Sustainable Conversion Reaction Applicable to High-Capacity Zinc Storage in Mildly Acidic Aqueous System

We introduce an unexpected finding of the de/protonation associated conversion reaction occurred in K2V3O8 as a promising cathode material for zinc-ion batteries. The structure undergoes a conversion reaction between amorphous V5+ 2O5 and V3+OOH upon cycling when a cut-off voltage up to 1.9 V is applied. A combination of operando X-ray diffraction, in situ Raman spectroscopy, X-ray photoelectron spectroscopy, time-of-flight secondary-ion mass spectroscopy, and operando pH measurement analyses reveal that the reaction of the proton (H+) is indispensable for progression of the conversion reaction. The conversion reaction results in a large reversible capacity of 362 mAh g−1 (~97 % of theoretical capacity) at 0.1 C (37 mA g−1) on discharge and an activity even at a rate of 7 C (187 mAh g−1), with the two-electron reaction by the V5+/3+ redox pair evidenced by operando X-ray absorption spectroscopy analysis. These findings underscore the importance of conversion reversibility associated with the proton reaction for a high cut-off voltage, contributing additional capacity to reach the theoretical capacity for cathode materials of zinc-ion batteries in mildly acidic aqueous systems.

Synthesis and properties of manganese-doped ZnO@2Mn1−xMxCO3 composite cathode material for zinc-ion batteries

Synthesis and properties of manganese-doped ZnO@2Mn1−xMxCO3 composite cathode material for zinc-ion batteries

Carbon reduction assist structured preparation stable three-dimensional V6O13 for durable aqueous zinc-ion batteries

Among various zinc-ion batteries (ZIBs) cathodes, vanadium-based oxides have received a great deal of research due to their high theoretical specific capacity. However, the severe problem of dissolution and sluggish kinetics of Zn2+ diffusion in vanadium-based oxides limit their further development as cathode materials for ZIBs. Herein, a novel monoclinic V6O13 nanoflowers (VONs) cathode is synthesized via an in-situ surface carbon reduction method from orthorhombic V2O5 at specific temperature. Benefiting from the intrinsic open tunnel-like structure and mixed states V4+/V5+ of V6O13, which are beneficial to facilitate the diffusion of Zn2+ and improve electronic conductivity of VONs. In addition, the dissolution of vanadium in VONs is suppressed remarkably. Based on the synergy of the advantages, the ZIBs with VONs electrode show excellent electrochemical performances, including high specific capacity (420 mAh g−1 at 0.2 A g−1) and rate capability, especially long-term cycling stability (above 88.9% capacity retention after 6000 cycles). Moreover, the kinetics and mechanism of the Zn2+ storage and diffusion in VONs have been investigated by combining experimental data with density functional theory (DFT) calculations. This in-situ preparation strategy provides a new approach to regulate the structure and phase of vanadium-based oxides to meet the requirements of high-performance ZIBs.

A Novel Ni-doped ZnMn2O4/Mn2O3 nanocomposite synthesized by pulsed potential as superior zinc ion battery cathode material

The research and development of suitable cathode materials for Zn2+ storage is crucial to meet the large-scale energy storage application of zinc-ion batteries (ZIBs). However, manganese-based oxide cathodes, the most-studied category of cathode materials, suffer from capacity decline and weak electrical conductivity. Herein, Ni-doped ZnMn2O4/Mn2O3 nanocomposite has been synthesized using pulsed potential electrodeposition technique and then applied as cathode material for ZIBs. The Ni2+ doping effectively boosts the electrical conductivity and electrochemical performance of electrodes. Furthermore, simultaneous production of ZnMn2O4 /Mn2O3 nanocomposite as a two-phase compound and incorporation of Ni2+ in crystal structure leads to an improvement in reversibility and cyclability of Ni-doped ZnMn2O4/Mn2O3 nanocomposite. Moreover, the Ni-doped ZnMn2O4/Mn2O3 nanocomposite presents a specific capacity of 235.10 mAh g−1 (0.2 A g−1), higher than Undoped nanocomposite (215 mAh g−1). Besides, the Ni-doped ZnMn2O4/Mn2O3 nanocomposite shows superior electrochemical performance, with a reversible capacity of 114.67 mAh g−1 and capacity retention of 91.32%, obtained after 3000 cycles at 2 A g−1, while the Undoped -ZnMn2O4/Mn2O3 nanocomposite possesses the capacity of 61.85 mAh g−1 with 64.54% capacity retention at the same condition. The obtained results suggest that the synergistic effect of doping and two-phase compound synthesis provide new features for the practical application of ZIBs.