High-performance Aqueous Zinc-ion Batteries Research Articles

Construction of N-doped carbon/MnO nanoparticles/hollow carbon spheres nested structure with tunable valence state for high-performance aqueous zinc ion batteries enables 10000 cycling stability

The practical applications of manganese-based aqueous zinc ion batteries (AZIBs) have been hindered by issues such as structural collapse, dissolution of active substances, and poor conductivity. Herein, a novel N-doped carbon/MnO nanoparticles/hollow carbon spheres nested structure (HCSs@MnO@NC) is fabricated as the active cathode material for AZIBs by controlled carbothermal reduction strategy. The internal hollow structure mitigates the volume expansion of MnO and improves material stability. The Mn-O-C heterojunction structure accelerates charge transfer and enhances structural stability. By controlling the carbothermal reduction process to adjust the valence state, electrochemical determinations demonstrate that divalent manganese exhibits a higher capacitance contribution rate, which is conducive to a faster ion migration rate. In situ UV–vis is firstly employed to detect the change of Mn2+ concentration in the electrolyte, revealing a Mn2+ deposition phenomenon in addition to the ion embedding mechanism during the initial charge. Owing to these favorable structural characteristics, the prepared HCSs@MnO@NC cathode delivers a specific capacity of 320.5 mAh g−1 at 0.1 A g−1 and maintains an excellent capacity after 10,000 cycles at 3 A g−1. This work can provide a new pathway for constructing advanced AZIBs by optimizing the nanostructure of composite electrode materials.

Aluminium-doped vanadium nitride as cathode material for high-performance aqueous zinc-ion batteries

Aqueous zinc-ion batteries (AZIBs) are increasingly favored for their environmentally friendly and impressive energy storage performance. Vanadium nitride (VN) is receiving much attention as a cathode material for AZIBs due to its high electrical conductivity and controllable structure. However, the direct use of VN in AZIBs presents challenges such as sluggish kinetics, insufficient specific capacity and limited stability. Herein, a heteroatom doping strategy is utilized to improve the electrochemical energy storage performance of the VN by incorporating aluminium (Al) via a hydrothermal process and a subsequent calcination treatment. Electrochemical characterizations indicate that the as-synthesized aluminium-doped VN (Al-doped VN) exhibits an outstanding specific capacity of 544 mAh·g−1 at 1 A g−1 and retains a high rate capacity of 275.6 mAh·g−1 at 10 A g−1. Further studies show that the Al incorporation effectively modulates the electronic configuration of the VN, which accelerates the charge transfer kinetics and thus enhances the electrochemical storage performance of VN. The phase transformation mechanism of the Al-doped VN is also investigated and the results show that the VN undergoes partial conversion into Zn3(OH)2V2O7·2H2O during the charge/discharge process.

Efficient Preparation of Metal-Ion Intercalated Vanadium-Based Cathodes for High-Performance Aqueous Zinc-Ion Batteries: Na2V6O16·3H2O as an Example.

The inherent challenges associated with aqueous zinc ion batteries (AZIBs), such as low energy density and slow diffusion kinetics, pose significant obstacles to their widespread adoption as energy storage systems. These limitations mainly stem from the nongreen and complex preparation process of high-quality cathode materials. In this study, we propose an approach utilizing microwave-assisted ball milling to expedite the fabrication of vanadium-based intercalated nanomaterials, aiming at solving the problem of prolonged reaction at high temperatures, which is unavoidable in the preparation of anode materials. Na2V6O16 (NVO) nanorods were synthesized in just 40 min under aqueous solvent conditions. These nanorods exhibit remarkable electrochemical properties, including a high specific capacity of 564 mA h g-1 at 0.1 A g-1 and an excellent cycle life, maintaining 164.2 mA h g-1 after 5000 cycles at 5 A g-1. Additionally, the incorporation of Na+ into the electrolyte effectively mitigates the stripping of Na+ and the deposition of Zn dendrimers from NVO, further contributing to enhanced cycling stability. The findings of this study offer a promising approach to the rapid and efficient synthesis of high-quality ZIB cathode materials.

The formation of three-dimensional phosphorus-doped MoO2/C nanostructures for high-performance aqueous zinc-ion batteries

MoO2 is considered as a promising cathode for zinc ion batteries (ZIBs) due to its high electronic conductivity, high theoretical capacity, and other advantages. However, MoO2 shows significant volume changes during ion insertion/de-insertion, leading to a decrease in battery cycling performance. In this paper, a novel P-MoO2/C heterostructure was prepared by introducing carbon skeleton in situ and phosphorus doping subsequently. Due to the rigid carbon structure and oxygen vacancies, the structural degradation of MoO2 was inhibited during the zinc ions intercalation/de-intercalation. Compared with the undoped MoO2/C and commercial MoO2, P-MoO2/C demonstrates a superior cycle stability including a high initial discharge specific capacity of 197.3 mAh·g−1 at 0.1A·g−1 and 60.8 % capacity retention after 200 cycles at 1A·g−1. This works provides a new pathway for the design of specialized structures as well as the enhancement of zinc storage capabilities of MoO2.

Manipulating the d-band center of bimetallic molybdenum vanadate for high performance aqueous zinc-ion battery

Vanadium-based oxides have good application prospects in aqueous zinc ion batteries (AZIBs) due to their structures suitable for zinc ion extraction and intercalation. However, their poor conductivity limits their further development. The d-band center plays a key role in promoting adsorption of ions, which promotes the development of electrode materials. Here, a series of MoV2O8 compounds with oxygen defect (Od-MoV2O8) were synthesized by a simple hydrothermal process and a subsequent vacuum calcination process through strict control of the deoxidation time. Theoretical calculations reveal that the abundant oxygen vacancies in MoV2O8 effectively regulate the d-band center of the zinc ion adsorption site. This precise control of the d-band center enhances the zinc ion adsorption energy of MoV2O8, lowers the migration energy barrier for zinc ions, and ultimately significantly boosts zinc storage performance. The specific capacity is as high as 282.4 mAh/g after 100 cycles at 0.1 A/g, and it also shows excellent performance and outstanding cycle life. In addition, the maximum energy density of Od-MVO-0.5 (MoV2O8 sample deoxidized for 0.5 h) is 343.3 Wh kg−1. Importantly, the mechanism of Zn2+ storage in Od-MoV2O8 was revealed by the combination of in situ and ex situ characterization techniques.

A Clay-Based Quasi-Solid-State electrolyte with high cation selective channels for High-Performance aqueous Zinc-Ion batteries

A clay-based quasi-solid-state electrolyte was prepared using dimethyl sulfoxide (DMSO) intercalated kaolinite as the raw material to suppress the adverse effects of free water molecules on aqueous zinc-ion batteries (AZIBs). Based on the inherent water absorption and retention properties of clay kaolinite, as well as the interlayer modification, this clay-based quasi-solid-state electrolyte not only achieved a low water content but also exhibited a strong water binding effect, which restricted the HER and side reactions involving water participation. Furthermore, the intercalation of DMSO increased the number of negative charges on the surface of kaolinite, resulting in the formation of a continuous spatial electrostatic field area around the kaolinite particles, which played a role in cation selectivity. The ionic transference number of the quasi-solid-state electrolyte reached 0.91. Additionally, the intercalation of DMSO broadened the interlayer ionic transport channels of kaolinite, further enhancing the transport efficiency of Zn2+ in the quasi-solid-state electrolyte, achieving uniform deposition of Zn2+ on the surface of the Zn anode, and suppressing dendrite growth to maintain a stable quasi-solid-state electrolyte/Zn anode interface. Zn||MnO2 battery assembled with this electrolyte demonstrated a discharge specific capacity of 301 mAh/g at a current density of 60 mA g−1. The Zn||MnO2 battery could be stably cycled for 1000 cycles at a current density of 150 mA g−1, and after 1000 cycles, the battery still maintained a discharge specific capacity of 248.2 mAh/g with a capacity retention rate of 84.8 %, showing excellent capacity performance and cycle stability. The Zn||MnO2 pouch battery could still provide stable power under heavy pressure, bending, and continuous tapping and had the potential for use in flexible batteries.

Layered MnO2@PDA as cathode material toward high-performance aqueous zinc-ion batteries

Aqueous zinc-ion batteries (AZIBs) can benefit from a deep understanding of the electrochemical reaction mechanism of cathode materials, which can assist in resolving issues such as cathode dissolution and electrostatic interactions. We reported a straightforward two-step synthesis of polydopamine coated MnO2 (MnO2@PDA) and revealed the energy storage mechanisms in AZIBs. The layered structure of MnO2 creates a generous passage for the insertion of H+/Zn2+ ions. Simultaneously, the plethora of functional groups within PDA exerts a robust desolvation effect, bolstering the transfer rate of H+/Zn2+. This effect significantly enhances the overall efficiency and performance of cathode. The AZIBs, incorporating MnO2@PDA cathode material, consequently exhibit a satisfactory cycling capacity (412 mAh g−1 at 0.1 A g−1) and a superb specific energy (561.6 Wh kg−1 at 136.34 W kg−1). This work provides a new path for design strategies and catalytic mechanisms of MnO2@PDA cathode.

Boosting the synergistic activation of δ-MnO2 as cathode for aqueous zinc-ion batteries through Ni, Co co-doping

Layered δ-MnO2 is regarded as a promising cathode material for high-performance aqueous zinc-ion batteries (AZIBs) due to the sufficient interlayer spacing for the accommodation and migration of charge carriers. However, the sluggish activation process limits the reversible capacity, thus prevent their application. In this study, Ni-Co co-doped layered δ-MnO2 was designed to enhance ion diffusion capability and cycling stability. The influencing mechanism of Ni and Co on the long activation process are proposed by a comparative analysis between single doping and co-doping approaches. Specifically, the optimized co-doped δ-MnO2 maintained a high specific capacity of 200.2 mAh·g−1 with a capacity retention of 97.40 % after 700 cycles at 1 A·g−1. The co-doping approach exhibited a synergistic effect in suppressing Mn dissolution and enhancing ion diffusion capability. These findings provide new directions on boosting the synergistic activation process of manganese oxide and shed lights on the rational design of low-cost and high-safe batteries.

CeO2 anchored in VO2@C rambutan-like microsphere achieving advanced zinc storage

Low-cost and high-safety aqueous zinc ion batteries (AZIBs) show great potential in energy storage for the grid. We propose a strategy to construct the self-assembled microspheres with the cerium oxide nanocrystals anchored on B-phase vanadium dioxide nanobelts, which are encapsulated by carbon (CVC), as cathode for high capacity and cycle stability of AZIBs. The rambutan-like structure with large specific surface area provides more active sites for the overall improvement of reaction kinetics; the carbon layer relieves vanadium dioxide from dissolving in the electrolyte while enhancing electron transfer rate; and electrocatalytic activity of cerium oxide accelerates redox reaction to enhance the performance of the cells. Consequently, the CVC electrode exhibits excellent electrochemical properties, including a reversible specific capacity (490 mAh g−1 at 0.1 A g−1), incredible cycle (84 % capacity retention after 1000 cycles at 5 A g−1). The excellent performance demonstrates the correctness of the combined internal and external modification strategy, while the simple hydrothermal method and inexpensive raw materials point to a new direction for the large-scale preparation of high-performance aqueous zinc ion batteries.

Fabrication of carbon-coated V2O5-x nanoparticles by plasma-enhanced chemical vapor deposition for high-performance aqueous zinc-ion battery composite cathodes

Fabrication of carbon-coated V2O5-x nanoparticles by plasma-enhanced chemical vapor deposition for high-performance aqueous zinc-ion battery composite cathodes

Bimetallic ions pre-intercalated hydrated vanadium oxides for high-performance aqueous zinc-ion batteries

A new generation of rechargeable batteries known as Aqueous Zinc-Ion Batteries (AZIB) offers benefits including affordability, eco-friendliness, dependability, and safety. Hydrated vanadium oxides (V2O5·nH2O) show potential as cathodes for AZIB due to their layered structure and multivalent properties. However, the zinc storage performance is limited by the structural instability and slow zinc ion mobility. In this work, TiK-VOH (the bimetallic ions system of Ti4+ and K+ co-pre-intercalated in V2O5·nH2O) with lamellar fish scale-like structure is synthesized using a simple sol-gel method. The high positive charge density of the tetravalent Ti4+ is more beneficial to attract the electrons in the V-O layer and regulate the layer spacing (12.1 Å), which not only improves the diffusion kinetics of zinc ions, but also acts as a pillar to stabilize the layer structure. K+ mainly plays the role of improving electrical conductivity, and then accelerates the charge transfer in the electrode reaction process. Auxiliary density functional theory simulation further confirms that the diffusion energy barrier and Fermi level are optimized by pre-intercalating bimetallic ions. Based on the synergistic effect of Ti4+ and K+, the TiK-VOH material shows excellent zinc storage performance, the highest specific capacity of TiK-VOH reaches 393.4 mAh g−1 at a current density of 0.2 A g−1, even at 10 A g−1 (increased by 20 times), it still maintains a discharge specific capacity of 202 mAh g−1 with a capacity retention rate of 94 % after 2000 cycles, the overall performance is much better than the Ti-VOH and K-VOH. This work offers an alternative perspective for the modification of vanadium-based cathode of AZIBs.

A Bio-Inspired Multifunctional Hydrogel Network with Toughly Interfacial Chemistry for Dendrite-Free Flexible Zinc Ion Battery.

Flexible and high-performance aqueous zinc-ion batteries (ZIBs), coupled with low cost and safe, are considered as one of the most promising energy storage candidates for wearable electronics. Hydrogel electrolytes present a compelling alternative to liquid electrolytes due to their remarkable flexibility and clear advantages in mitigating parasitic side reactions. However, hydrogel electrolytes suffer from poor mechanical properties and interfacial chemistry, which limits them to suppressed performance levels in flexible ZIBs, especially under harsh mechanical strains. Herein, a bio-inspired multifunctional hydrogel electrolyte network (polyacrylamide (PAM)/trehalose) with improved mechanical and adhesive properties was developed via a simple trehalose network-repairing strategy to stabilize the interfacial chemistry for dendrite-free and long-life flexible ZIBs. As a result, the trehalose-modified PAM hydrogel exhibits a superior strength and stretchability up to 100 kPa and 5338 %, respectively, as well as strong adhesive properties to various substrates. Also, the PAM/trehalose hydrogel electrolyte provides superior anti-corrosion capability for Zn anode and regulates Zn nucleation/growth, resulting in achieving a high Coulombic efficiency of 98.8 %, and long-term stability over 2400 h. Importantly, the flexible Zn//MnO2 pouch cell exhibits excellent cycling performance under different bending conditions, which offers a great potential in flexible energy-related applications and beyond.

Flash Joule Heating Synthesis of Layer-Stacked Vanadium Oxide/Graphene Hybrids within Seconds for High-Performance Aqueous Zinc-Ion Batteries.

Vanadium oxides have been regarded as highly promising cathodes for aqueous zinc-ion batteries (ZIBs). However, obtaining high-performance vanadium oxide-based cathodes suitable for industrial application remains a significant challenge due to the need for cost-effective, straightforward, and efficient preparation methods. Herein, we present a facile and rapid synthesis of a composite cathode, consisting of layer-stacked VO2/V2O5 and graphene-like carbon nanosheets, in just 2.5 s by treating the commercial V2O5 powder via a flash Joule heating strategy. When employed as the cathode for ZIBs, the resulting composite delivers a comparable rate capacity of 459 mA h g-1 at 0.2 A g-1 and remarkable cycle stabilities of 355.5 mA h g-1 after 2500 cycles at 1.0 A g-1 and 169.5 mA h g-1 after 10,000 cycles at 10 A g-1, respectively. Further electrochemical analysis reveals that the impressive performance is attributed to the accelerated charge transfer and the alleviated structure degradation, facilitated by the abundant sites and a built-in electric field of the layer-stacked VO2/V2O5 heterostructure, as well as the excellent conductivity of graphene-like carbon nanosheets. This work introduces a unique approach for ultrafast and low-cost fabrication of high-performance vanadium oxide-based composite cathodes toward efficient ZIBs.

An organic cathode integrating carbonyl and imino groups for high-performance aqueous zinc-ion battery with air self-charging ability

Air-self-charging aqueous zinc-ion batteries (AZIBs) are a promising system applied in some special occasions, where no external power source can be provided to recharge the battery. Here, a new π-conjugated aromatic compound 2,7,12-tri(4H-1,2,4-triazol-4-yl)-1H-pyrrolo [3,4-b]pyrrolo[3′,4′:5,6]pyrazino[2,3f]pyrrolo[3′,4′:5,6]pyrazi-no[2,3−h]quinoxaline-1,3,6,8,11,13(2H,7H,12H)-hexaone (THQH) is reported. Because THQH contains multiple redox-active groups (CN and CO) and its insolubility in 2 M ZnSO4, as the cathode material of flexible/coin-type AZIBs, it owns outstanding discharge specific capacity, higher-rate performance and longer cycle life. Various ex-situ experiments and theoretical calculation revealed H+ and Zn2+ participated in the THQH cathode reaction. Notably, as the discharged flexible Zn//THQH battery is exposed to air, it can be self-recharged via the redox reaction between oxygen in air and the discharged THQH cathode, along with H+ ions removal. The flexible Zn//THQH battery can deliver a discharge capacity of up to 566 mA h g−1 at 0.5 A g−1, a higher-rate capability and an excellent self-charging cycle stability (31 cycles) after exposed to air for 28 h, displaying an excellent reusability. This work paves a way for the development of high-performance flexible air self-charging AZIBs.

Inorganic-organic hybrid heterogeneous membrane for zinc protective layers in high-performance aqueous zinc ion batteries

Aqueous zinc-ion Batteries (AZIBs) suffer from stability and performance limitations due to challenges related to the zinc (Zn) metal anode, including hydrogen evolution reaction (HER), metal corrosion, and Zn dendrite formation. To mitigate these issues, researchers are developing innovative coatings and protective layers for Zn anodes, focusing on enhancing ion conductivity, electrochemical inertness, mechanical strength, and processability. Hybrid organic-inorganic heterostructure coating materials with silver nanowires (Ag NWs) encapsulated with Polypyrrole (Ag/PPy) have shown promise in addressing these challenges. The Zn anode coated with Ag/PPy layers and paired with an α-MnO2 cathode, achieved an impressive initial capacity of 302 mAh/g at a current density of 0.5 A/g. Remarkably, it retained a substantial capacity of 283 mAh/g after 300 cycles at a current density of 0.5 A/g, demonstrating a 94 % capacity retention rate. Moreover, the symmetry cell using this anode maintains stable Zn deposition/stripping overpotentials even at a high current density (a rate of 10C) for over 175 h. These findings highlight the potential of Ag/PPy coatings as a viable approach for enhancing the surface chemistry and physical properties of the Zn metal anode, paving the way for a wider use of AZIBs.

Fe doping 1T phase MoS2 with enhanced zinc-ion storage ability and durability for high-performance aqueous zinc-ion batteries

Fe doping 1T phase MoS2 with enhanced zinc-ion storage ability and durability for high-performance aqueous zinc-ion batteries

Construction of sodium-poor and oxygen defect-rich vanadium oxide nanobelts for high-performance aqueous zinc-ion batteries

Construction of sodium-poor and oxygen defect-rich vanadium oxide nanobelts for high-performance aqueous zinc-ion batteries

Dual-Ion-Doped Hydrated Vanadium Oxides Nanowires As Cathode Materials for High-Rate Aqueous Zinc Ion Batteries

Due to environmental-friendliness, high safety and stability, high theoretical capacity as well as low cost, aqueous zinc ion batteries (AZIBs) are budding as attractive alternatives for large-scale energy storage applications. However, the lack of suitable positive electrode materials becomes the main issue for AZIBs to pursue high energy density and excellent rate capability. Herein, the dual-ion-doped hydrated vanadium oxide nanowires (VOH) are synthesized through hydrothermal method, which is suitable to be cathode materials for AZIBs. Through metal ions and crystal water pre-intercalation, the interlayer spacing of (001) becomes larger, which is proposed to have better capability to accommodate Zn2+. Moreover, the pre-intercalated metal ions can serve as structural pillars between layers, providing excellent stability during discharging/charging process. In this study, the novel dual-ion-doped VOH exhibits more than 420 mA h g−1 at 0.1 A g−1 as well as more than 260 mA h g−1 at 5 A g−1. In addition, it can retain more than 80% capacity after 500 cycles at 5 A g−1. The energy storage mechanism of dual-ion-doped VOH is revealed via operando x-ray absorption near edge spectroscopy. This study implies that this dual-ion-doped VOH nanowires can serve as suitable positive electrode materials for high-performance aqueous zinc ion batteries.

Zn-doped manganese tetroxide/graphene oxide cathode materials for high-performance aqueous zinc-ion battery

Zn-doped manganese tetroxide/graphene oxide cathode materials for high-performance aqueous zinc-ion battery

Design and Conformation of Separators for High-performance Aqueous Zinc-Ion Batteries.

Aqueous zinc-ion batteries (AZIBs) are considered promising candidates for large-scale energy storage due to their high safety, low cost, and environmental friendliness. As a core component, separator plays a unique yet oftentimes overlooked role in providing electrochemical stability in AZIBs. This concept focuses on the exquisite structure-property relationship of separators, highlighting three forms of these components and their structural design requirements, i.e., traditional membranes, solid-stateelectrolytes, and electrode coatings. The mechanism by which separators influence the zinc anode and the cathode is discussed. The article also identifies the challenges and potential future directions for functional separators in the development of high-performance AZIBs.