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[Display omitted] Zinc metal anodes in aqueous electrolytes commonly face challenges such as dendrite growth and undesirable side reactions, limiting their application in the field of aqueous zinc-ion batteries (AZIBs) for energy storage. Drawing inspiration from industrial practices involving molybdenum salt solutions for metal modification, a polyoxometalate solution was formulated as a passivation solution for zinc anodes (referred to as MO solution). The formed passivation layer, referred to as the MO layer, exhibited a uniform and protective nature with a thickness of approximately 10 μm. The experimental results demonstrated that this passivation layer effectively suppressed side reactions at the zinc anode interface, as evidenced by lower corrosion current density for MO-Zn anodes. Additionally, the newly plated Zn was uniformly deposited atop the MO layer, ensuring coating integrity and inhibiting dendrite growth. As a result, under more demanding conditions such as a larger current of 8 mA cm−2, the MO-Zn anode displayed an extended cycle life exceeding 420 h in a symmetric battery, with an overpotential as low as 98 mV. This performance significantly outperformed that of commercially available pure Zn foils (with a cycle life of 60 h and an overpotential of 192 mV). Notably, a self-made Na-doped V 2 O 5 served as the cathode (referred to as NaVO), forming the MO-Zn//NaVO full battery. Even under high current test conditions of 2 A/g, the specific capacity of the MO-Zn//NaVO full battery remained substantial at 152.83 mAh/g after 1000 cycles. Furthermore, pouch batteries assembled with NaVO//MO-Zn successfully illuminated small bulbs. This study offers a viable optimization strategy for AZIB anodes and demonstrates the potential of using polyoxometalate solution for etching zinc anodes to inhibit dendrite growth and interfacial corrosion of zinc metal anodes. [ABSTRACT FROM AUTHOR]

[Display omitted] Aqueous zinc ion batteries (AZIBs) are receiving broad attention owing to their high safety and low cost. However, the high mechanical strength and irreversible growth of zinc dendrites limit the practical application of AZIBs. Herein, regular mesh-like gullies are built on the surface of zinc foil (M150 Zn) by using simple model pressing method and stainless steel mesh as a mold. Due to the charge-enrichment effect, zinc ion deposition and stripping will be preferentially carried out in the grooves to keep the outer surface flat. In addition, zinc is exposed to 002 crystal surface in the gully after being pressed, and the deposited zinc is more inclined to grow at a small angle, so that it has a sedimentary morphology parallel to the basement. Consequently, at a current density of 0.5 mA cm−2, the M150 zinc anode has a voltage hysteresis of only 35 mV and a cycle life of up to 400 h (relative to a zinc foil of 96 mV and 160 h). Even more imposing is that the full cell has a capacity retention of approximately 100% after 1000 cycles at 2 A g−1 and a specific capacity of almost 60 mAh g−1 when activated carbon is used as the cathode. It is a promising method to improve the stable cycle performance of AZIBs by using a simple method to realize the non-prominent dendrites on the surface of zinc electrode. [ABSTRACT FROM AUTHOR]

Aqueous zinc ion batteries (AZIBs) are well-suited for current energy storage technologies due to their high safety and low cost. However, battery failures resulting from dendrites and side reactions restrict their widespread application. Here, we designed a polyacrylonitrile (PAN)-zinc trifluoromethanesulfonate (ZnTFSI) nanofibre synergistic glass fibre (PZ-GF) to modulate the interfacial deposition kinetics. The effective coordination of numerous CN functional groups within PZ, in conjunction with Zn2+, results in the homogeneous dispersion of the electric field across the electrode, which promotes the uniform deposition of Zn2+ on the zinc anode and thus significantly inhibits the rapid growth of zinc dendrites. ZnTFSI is hydrophilic and has strong hydrogen bonding interactions with the H 2 O molecule so that the separator can be used as a molecular sieve to regulate the flux of H 2 O, promote the desolvation of hydrated zinc ions, and inhibit side reactions.Tests of the initial nucleation overpotential of the symmetric battery and calculation of the activation energy reflect that PZ-GF has a smaller nucleation energy barrier and enhanced kinetic effect. And the zinc symmetric battery with PZ-GF film shows an ultra-long cycle stability of 1200 cycles with a capacity retention of 75 % even at 0.5 A g−1 for the Zn//VO 2 full cells. [Display omitted] • PZ films have a more uniform and dense pore structure than glass fibres. • -CN in PZ formed N Zn bonds with Zn and promotes the uniform deposition of Zn. • After 1200 cycles, the capacity of full cells assembled with PZ-GF is maintained by 75 %. [ABSTRACT FROM AUTHOR]

Zinc metal anodes produce side reactions such as dendrite growth and surface corrosion during cycling, leading to premature battery failure. For this reason, we propose an anodic protection strategy for coating sodium carboxymethyl cellulose (CMC) hydrogel material on the surface of zinc foil. This non-conducting 3D porous interconnected network coating acts as a barrier to regulate the flux of zinc ions and electric field distribution, induces zinc to exhibit 3D deposition, and inhibits the growth of dendritic protrusions.The Zn@CMC anode possesses enhanced desolvation capability, which accelerates the rapid transfer of zinc ions, exhibits enhanced kinetics, and inhibits the occurrence of side reactions. The symmetric cell based on CMC hydrogel can be recycled for 1000 h at a current density of 0.5 mA cm−2 with low voltage hysteresis, and the Zn@CMC//Na-doped VO 2 full cell can maintain a discharge specific capacity of 119 mAh g−1 after 1500 cycles, which is of good practical performance. This study provides a new perspective for the introduction of CMC hydrogel for interfacial modification, which is of reference value for solving interfacial problems. [Display omitted] • Self-assembled CMC hydrogel coating based on zinc foil surface. • Symmetric cells can be stably cycled for 1000 h at 0.5 mA cm−2 with low voltage hysteresis. • Non-conducting 3D porous interconnection network coating can be used as an ion sieve to induce 3D deposition of Zn. • Zn@CMC has strong desolvation ability and stronger kinetics. [ABSTRACT FROM AUTHOR]

• Zinc spheres prepared by extrusion melting expose a high proportion of (002) crystal plane. • Planarly oriented (002) crystal plane induces Zn2+ deposition at small angles. • The thread morphology and (002) crystal plane work synergistically to increase surface active sites and reduce the electrode reaction energy barrier. Excessive dendrite growth will seriously affect the future development of aqueous zinc-ion batteries. Therefore, reducing dendrite formation during anode cycling has important practical significance for ZiBs. Previous research have shown that the (002) crystal plane induces zinc to deposit on the anode surface at a small angle, thereby mitigating the generation of longitudinal dendrites and thereby improving cycle performance. This paper uses extrusion method to prepare zinc foil with high (002) crystal plane ratio, in which the diffraction peak intensity ratio of (002)/(100) crystal plane is about 130.The assembled symmetrical battery can operate stably for 400 h at 0.5 mA cm−2 and 0.5 mAh cm−2, and obtains a cycle life of 160 h at 20 mA cm−2 and 20 mAh cm−2. The surface of the anode after cycling exhibits thin and large deposited flakes, fully exhibiting the characteristics of the (002) crystal plane. In terms of plating/stripping kinetics, because the (002) crystal plane has high adsorption energy for zinc, PZn obtains a lower polarization voltage and a larger exchange current density (4.56 mA cm−2). In addition, due to the low surface energy of the (002) crystal plane, which also shows a lower activation energy (17.95 kJ mol−1), lowers the reaction energy barrier, and reduces the difficulty of the electrode reaction. In terms of practicality, it has approximately 140 mAh g−1 at 1 A g−1 in a complete cell consisting of Na sodium-doped V 2 O 5 cathode. It also has a 94 % capacity retention rate after cycling. This article verifies the influence of rich (002) crystal planes on the performance of metallic zinc anodes, and provides guidance for the future optimization of crystal planes of zinc anodes. [Display omitted] [ABSTRACT FROM AUTHOR]

• Electrostatic spinning construction of 3D PVDF/PAN @Zn powder frameworks. • Mechanical stresses on fibre filaments and uniform stripping of zinc powder inhibit dendrite growth. • Larger surface area, suitable pore size and tunable N/P ratio are key merits. Zinc foil metal anodes in aqueous zinc ion batteries (AZIBs) are impaired by uncontrollable dendrite growth, resulting in low Coulombic efficiency (CE) and limited lifetime. The tunability of zinc powder provides a perfect alternative for anodes. But their rough spherical surfaces possibly make them more susceptible to corrosion and dendrite growth. We hereby utilise electrostatic spinning to weave zinc powder into polyacrylonitrile/ Polyvinylidene fluoride (PVDF/PAN) fiber filament to produce a new three-dimensional porous zinc anode (PF@Zn). Stable and flexible structure of the constructed fiber filament framework avoids direct contact of the aqueous electrolyte with the collector while relieving the stresses generated by dendrite growth. Moreover, when galvanizing or stripping, the zinc powder woven into the fiber network efficiently homogenizes the Zn2+ ion flux for a stable zinc cycle. Accordingly, the PF@Zn anode battery has a superior cycle life (240 h) and an increased Coulombic efficiency (99.1 %). An assembled C//PF@Zn capacitor has an impressive 96.6 % capacity retention after 3000 cycles. The study offers a scalable approach to modifying metal powder electrodes and transforming them into high-performance batteries. [ABSTRACT FROM AUTHOR]

Aqueous zinc-ion batteries (AZIBs) are expected to be the next generation of energy storage devices, but severe dendrite growth hindering the large-scale application of AZIBs. In this paper, a citric acid (CA) etching method is used to optimize zinc anode, which is referred to as CA-Zn. After citric acid etching, the zinc anode surface was exposed to a high proportion of (002) crystal planes, and the stable (002) crystal planes inhibited the formation of zinc surface by-products. Moreover, acid etching etched micro-grooves on the zinc surface, which increased the electrochemically active surface area of the zinc anode. And the plating/stripping kinetics of Zn/Zn2+ was enhanced. Consequently, the CA-Zn symmetric battery has a stable cycle of 550 h at 1 mA cm−2 and 1 mAh cm−2. AZIBs composed of CA-Zn and activated carbon showed a specific capacity of up to 83.5 mAhg−1 and CE close to 100% during cycling 1500 cycles at a current density of 0.5 A g−1. This paper explores a new method to protect zinc metal by citric acid etching, which provides a new idea for future research. [Display omitted] • A simple method of etching zinc anodes surface in citric acid • More nucleation sites were constructed on the zinc surface. • The zinc anodes with more (002) crystal planes exposure were obtained. • The zinc anodes etched with citric acid have excellent electrochemical properties. [ABSTRACT FROM AUTHOR]

Dendritic problems on the anodes of aqueous zinc batteries limit their development, resulting in reduced stability and lifetime. In this paper, a dual-function molecular sieve is proposed. The molecular sieve consists of 3D fibrous whiskers compounded with 2D MXene, with the zinc foil used directly as a receptor plate and assembled directly on the surface as a zinc anode by electrostatic spinning. Zinc ion transport through 3D fibrous whiskers promotes homogeneous ion flux, while Ti 3 C 2 T x MXene and its abundant functional groups provide a highly reversible zinc plating/stripping process; the low lattice mismatch (∼10%) allows uniform nucleation of the transported Zn along the (0002) face. The synergistic action of the two inhibits the proliferation of dendrites on the zinc anode. Consequently, MF@Zn∥MF@Zn symmetric cells achieved stable cycling for 200 h at high current densities of 5 mA - 5 mAh cm−2. Due to the smooth growth effect of MXene, 3D nucleation behaviour and remarkably low nucleation currents (10 mA) were observed in the Chrono Amps method (CA) method. Matched with carbon cathode, MF@Zn∥C shows the superior capacity and almost 100% retention after 2000 cycles compared to RZn. The experimental results confirm that MF@Zn 3D fibre whiskers constructed directly on zinc foil can significantly improve the performance of the cells, providing a new idea for other researchers. [Display omitted] • Fibre whisker is constructed by direct spinning on zinc foil. • MXene doping induced Zn plane deposition. • The product has better life, rate and capacity in Zibs. • Larger surface area, suitable pore size and induction of MXene are key merits. [ABSTRACT FROM AUTHOR]