Electrochemically Induced Structural and Morphological Evolutions in Nickel Vanadium Oxide Hydrate Nanobelts Enabling Fast Transport Kinetics for High-Performance Zinc Storage

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.

Multi-Channel Engineering of 3D Printed Zincophilic Anodes for Ultrahigh-Capacity and Dendrite-Free Quasi-Solid-State Zinc-Ion Microbatteries

Zinc-ion microbatteries (ZIMBs) are regarded as one of most promising miniaturized energy storage candidates owing to their high safety, compatible device size, superior energy density, and cost efficiency. Nevertheless, the zinc dendrite growth during charging/discharging and the inflexible device manufacturing approach seriously restrict practical applications of ZIMBs. Herein, we report a unique material extrusion 3D printing approach with reinforced zincophilic anodes for ultrahigh-capacity and dendrite-free quasi-solid-state ZIMBs. A 3D printed N-doped hollow carbon nanotube (3DP-NHC) multichannel host is rationally designed for desirable dendrite-free zinc anodes. Favorable structural metrics of 3DP-NHC hosts with abundant porous channels and high zincophilic active sites enhance the ion diffusion rate and facilitate uniform zinc deposition behavior. Rapid zinc-ion migration is predicted through molecular dynamics, and zinc dendrite growth is significantly suppressed with homogeneous zinc-ion deposition, as observed by in situ optical microscopy. 3D printed symmetric zinc cells exhibit an ultralow polarization potential, a glorious rate performance, and a stable charging/discharging process. Accordingly, 3D printed quasi-solid-state ZIMBs achieve an outstanding device capacity of 11.9 mA h cm-2 at 0.3 mA cm-2 and superior cycling stability. These results reveal a feasible approach to effectively restrain zinc dendrite growth and achieve high performance for state-of-the-art miniaturized energy storage devices.

Design of internally integrated in-plane electrodes for superior flexible hybrid zinc-ion capacitor devices

A unique configuration based on internally integrated electrodes is proposed for flexible hybrid zinc-ion capacitor (HZIC) devices. An in-depth charge storage process is studied, confirming the high electrochemical promise of HZICs for future practical applications.

A novel strategy via electrode catalysis induced nano transformation for lithiated-bimetallic-oxides to avoid the long activation process of advanced lithium-ion batteries

Improving the anode materials for lithium-ion batteries with a long activation process, poor cycle stability, and low Coulomb efficiency is of great significance for developing novel high-performance anode materials. Orthorhombic LiVMoO₅ with high specific capacity was applied to the anode field of lithium-ion battery for the first time. However, the activation process led to its poor cyclic performance. By adopting a novel nano-transformation treatment process in a water and oxygen environment, we effectively avoided the long-term activation process. The specially treated LiVMoO₅ electrode (STLVME) exhibited excellent reversible specific capacity (∼1100 mA h g^-1) and rate cycle stability (capacity retention rate ∼100%). Furthermore, GITT and EIS also showed that compared with the primitive LiVMoO₅ electrode (LVME), smaller internal resistance and a higher Li⁺ diffusion coefficient were caused using the novel treatment process, significantly improving the rate cycle stability. Using in situ XRD and ex situ characterization, we illustrated the lithium storage mechanism of LVME and STLVME. In addition, the practical application potential of LVME and STLVME was also explored by assembling the full cells. Because the long-term activation process was effectively avoided, the full-cell exhibited amazing cycle stability, indicating that STLVME can be considered a promising potential anode for practical applications in energy storage devices.

High performance aqueous zinc battery enabled by potassium ion stabilization

Aqueous zinc ion batteries (AZIBs) are highly competitive in the energy storage systems due to their feature with operation safety and environmental friendliness. However, the sluggish diffusion kinetics of Zn²⁺ and inferior cathode circulation hinder their widespread application. Herein, we assemble a highly durable zinc ion battery by intercalating K⁺ into V₂O₅ nanolayers. The K⁺ pre-intercalation can buffer the lattice expansion of the electrode materials and reduce the internal stress. In addition, the stable K⁺ acts as a "pillar" to protect the layered structure of V₂O₅ materials from collapse during operation cycling. It delivers a reversible capacity of 479.8 mAh g^-1 at 0.2 A g^-1 and achieves excellent cyclic stability with a retention rate of 91.3% (10 A g^-1) after 3000 cycles. The cell still maintains excellent specific capacity at high work temperature.

New Insight on K2 Zn2 V10 O28 as an Advanced Cathode for Rechargeable Aqueous Zinc-Ion Batteries

Aqueous zinc-ion batteries (ZIBs) have recently attracted people's extensive attention in their application in energy storage systems resulting from their exclusive characteristics of low cost and environmental compatibility. However, finding suitable cathode materials continues to be the major challenge. Polyoxovanadates (POVs), as an important branch of polyoxometalates (POMs), are considered as a promising electrode material for reversible aqueous ZIBs relying on the flexible valence state of V. Herein, POVs (K₂ Zn₂ V₁₀ O₂₈ : KZVO) are reported as an advanced cathode for storing Zn²⁺ , which delivers a high discharge capacity of 223.4 mAh g^-1 at 0.1 A g^-1 , considerable energy density (182.9 Wh kg^-1 ) and power density (40.38 W kg^-1 ), and robust cyclic performance. In addition, the dynamic properties of the KZVO/Zn battery are revealed by pseudocapacitance analysis and GITT tests. Meanwhile, the storage mechanism of Zn²⁺ is further analyzed by ex situ XRD, XPS, TEM, and HRTEM. Overall, this work not only draws up a cathode material for the POMs system in aqueous ZIBs, but also demonstrates that POMs are the rising star in energy storage and electric energy applications.

MgMoO4 as an anode material for lithium ion batteries and its multi-electron reaction mechanism

Single-phase magnesium molybdate, MgMoO4, is successfully synthesized by a facile sol-gel method. Attributed to the multielectron reaction and the synergistic effect of the elements molybdenum (Mo) and magnesium (Mg), the...

The facile synthesis and electrochemical performance of Ni2V2O7 as a novel anode material for lithium-ion batteries

The single-phase binary nickel vanadate Ni2V2O7 was successfully synthesized by a simple solid-state method to explore novel anode materials for lithium-ion batteries. After an activation process, the Ni2V2O7 electrode exhibited excellent electrochemical performance with a stable, high specific capacity of about 960 mA h g-1 at a current density of 100 mA g-1, which is attributed to the multiple valence states and the synergistic effect of the transition elements V and Ni. Even at a high current density of 2000 mA g-1, a stable specific capacity of about 400 mA h g-1 was still obtained. Considering the influence of the activation process on the electrochemical performance of the Ni2V2O7 electrode, we studied the origin of the excellent electrochemical performance, where the improved lithium diffusion coefficient and increased pseudocapacitive contribution caused by the activation process led to a significant improvement in the electrochemical performance, including rate capacity and cycle stability. By combining in situ X-ray diffraction (XRD) and ex situ X-ray photoelectron spectroscopy (XPS) methods, for the first time, we illustrate the detailed lithium storage mechanism of the Ni2V2O7 electrode during the lithium insertion/extraction process.

Regulation of arachidonic acid oxidation and metabolism by lipid electrophiles

Arachidonic acid (AA) is a precursor of enzymatic and non-enzymatic oxidized products such as prostaglandins, thromboxanes, leukotrienes, lipoxins, and isoprostanes. These products may exert signaling or damaging roles during physiological and pathological conditions, some of them being markers of oxidative stress linked to inflammation. Recent data support the concept that cyclooxygenases (COX), lipoxygenases (LOX), and cytochrome P450 (CYP450) followed by cytosolic and microsomal dehydrogenases can convert AA to lipid-derived electrophiles (LDE). Lipid-derived electrophiles are fatty acid derivatives bearing an electron-withdrawing group that can react with nucleophiles at proteins, DNA, and small antioxidant molecules exerting potent signaling properties. This review aims to describe the formation, sources, and electrophilic anti-inflammatory actions of key mammalian LDE.

Vanadium oxide bronzes as cathode active materials for non-lithium-based batteries

Lithium as critical resource prompted interest for non-lithium-based batteries. This highlight review discusses vanadium oxide bronzes as one of the material families being considered as cathode for non-lithium-based batteries.