As base metals, zinc and lead are widely developed in various types of deposits. Zinc and lead also form various types of independent deposits and are associated with a variety of critical metals. ...Zn-Pb deposits occupy an important position in the world, including volcanic-hosted massive sulphide (VHMS/VMS), magmatic–hydrothermal-associated skarn and/or epithermal types, sediment-hosted types (e.g., clastic-hosted sedimentary exhalative, SEDEX; carbonate-hosted Mississippi Valley type, MVT; sandstone-hosted type, SST; and shale-hosted type), and hydrothermal vein types. This Special Issue reprint aims to provide a comprehensive understanding of Zn-Pb deposits and associated critical metals, and promote global prospecting.
In the past decades, the world has witnessed the successful commercialization of “rocking‐chair”‐type lithium‐ion batteries with lithium metal free anodes. Owing to their safe, green, easy ...manufacturing, and cost‐efficiency characteristics, rechargeable zinc batteries have recently received more and more attention. However, the practical application of Zn metal batteries is hampered mainly by the dendritic growth of Zn metal anode, which leads to poor Coulombic efficiency, hazards, and various side reactions. Herein, the emerging “rocking‐chair”‐type Zn‐ion batteries are systemically reviewed with Zn host anodes instead of Zn metal anodes. As an introduction, the fundamental principles, advantages, and challenges of “rocking‐chair”‐type Zn‐ion batteries are discussed. Subsequently, the design principles and recent advances of cathode, anode, and electrolyte for “rocking‐chair” Zn‐ion batteries are summarized. To conclude, perspectives on the future of “rocking‐chair” Zn‐ion batteries are presented. It is hoped that this review may provide alternative directions for the design of Zn‐ion batteries.
This review systematically summarizes the emerging anodes, cathodes, and electrolytes for Zn‐metal free “rocking‐chair” Zn‐ion batteries. The fundamental principles, advantages, challenges, design principles, and recent advances of “rocking‐chair”‐type Zn‐ion batteries are summarized and discussed. Perspectives on the future of the field are also outlined.
The practical application of the Zn‐metal anode for aqueous batteries is greatly restricted by catastrophic dendrite growth, intricate hydrogen evolution, and parasitic surface passivation. Herein, a ...polyanionic hydrogel film is introduced as a protective layer on the Zn anode with the assistance of a silane coupling agent (denoted as Zn–SHn). The hydrogel framework with zincophilic –SO3− functional groups uniformizes the zinc ions flux and transport. Furthermore, such a hydrogel layer chemically bonded on the Zn surface possesses an anti‐catalysis effect, which effectively suppresses both the hydrogen evolution reaction and formation of Zn dendrites. As a result, stable and reversible Zn stripping/plating at various currents and capacities is achieved. A full cell by pairing the Zn–SHn anode with a NaV3O8·1.5 H2O cathode shows a capacity of around 176 mAh g−1 with a retention around 67% over 4000 cycles at 10 A g−1. This polyanionic hydrogel film protection strategy paves a new way for future Zn‐anode design and safe aqueous batteries construction.
A unique polyanionic hydrogel is employed as an artificial protective layer for reversible Zn‐metal anodes. The polyanions in the hydrogel framework facilitate a homogeneous zinc‐ion flux, and the Zn–O bonding strengthens the interface and suppresses surface corrosion and irregular Zn dendrites growth. This strategy could apply also to other aqueous metal batteries.
The hydrogen evolution in Zn metal battery is accurately quantified by in situ battery–gas chromatography–mass analysis. The hydrogen fluxes reach 3.76 mmol h−1 cm−2 in a Zn//Zn symmetric cell in ...each segment, and 7.70 mmol h−1 cm−2 in a Zn//MnO2 full cell. Then, a highly electronically insulating (0.11 mS cm−1) but highly Zn2+ ion conductive (80.2 mS cm−1) ZnF2 solid ion conductor with high Zn2+ transfer number (0.65) is constructed to isolate Zn metal from liquid electrolyte, which not only prohibits over 99.2% parasitic hydrogen evolution but also guides uniform Zn electrodeposition. Precisely quantitated, the Zn@ZnF2//Zn@ZnF2 cell only produces 0.02 mmol h−1 cm−2 of hydrogen (0.53% of the Zn//Zn cell). Encouragingly, a high‐areal‐capacity Zn@ZnF2//MnO2 (≈3.2 mAh cm−2) full cell only produces maximum hydrogen flux of 0.06 mmol h−1 cm−2 (0.78% of the Zn//Zn cell) at the fully charging state. Meanwhile, Zn@ZnF2//Zn@ZnF2 symmetric cell exhibits excellent stability under ultrahigh current density and areal capacity (10 mA cm−2, 10 mAh cm−2) over 590 h (285 cycles), which far outperforms all reported Zn metal anodes in aqueous systems. In light of the superior Zn@ZnF2 anode, the high‐areal‐capacity aqueous Zn@ZnF2//MnO2 batteries (≈3.2 mAh cm−2) shows remarkable cycling stability over 1000 cycles with 93.63% capacity retained at ≈100% Coulombic efficiency.
The hydrogen evolution in a Zn metal battery is accurately quantified by in situ battery–gas chromatography–mass analysis. Meanwhile, a highly electronically insulating but highly Zn2+ ion conductive ZnF2 solid ion conductor is utilized to isolate Zn metal from liquid electrolyte, which not only prohibits over 99.2% parasitic hydrogen evolution reaction during cycling but also guides uniform Zn electrodeposition.
Benefiting from the advantageous features of high safety, abundant reserves, low cost, and high energy density, aqueous Zn‐based rechargeable batteries (AZBs) have received extensive attention as ...promising candidates for energy storage. To achieve high‐performance AZBs with high reversibility and energy density, great efforts have been devoted to overcoming their drawbacks by focusing on the modification of electrode materials and electrolytes. Based on different cathode materials and aqueous electrolytes, the development of aqueous AZBs with different redox mechanisms are discussed in this review, including insertion/extraction chemistries (e.g., Zn2+, alkali metal ion, H+, NH4+, and so forth) dissolution/deposition reactions (e.g., MnO2/Mn2+), redox couples in flow batteries (e.g., I3−/3I−, Br2/Br−, and so forth), oxygen electrochemistry (e.g., O2/OH−, O2/O22−), and carbon dioxide electrochemistry (e.g., CO2/CO, CO2/HCOOH). In particular, the basic reaction mechanisms, issues with the Zn electrode, aqueous electrolytes, and cathode materials as well as their design strategies are systematically reviewed. Finally, the remaining challenges faced by AZBs are summarized, and perspectives for further investigations are proposed.
The main mechanisms, challenges, and most recent advances of various aqueous Zn‐based batteries (AZBs) are comprehensively reviewed. The development of the design of Zn anodes, electrolytes, cell configurations, and the modification of cathode materials are highlighted. Finally, future perspectives regarding different components are proposed. This review provides valuable instructions on the design of high‐performance AZBs.
With advantages such as high theoretical capacity, low cost, and nontoxicity, Zn metal has been widely investigated as an anode for aqueous batteries. However, the problems of dendrite formation and ...sustained corrosion originating from severe interfacial side reactions and uncontrolled Zn electrodeposition in aqueous electrolytes significantly slows down the practical application of Zn metal anodes. To address these issues, herein, an anti‐corrosion elastic constraint (AEC) is introduced that is built with nanosized TiO2 and polyvinylidene fluoride (PVDF) matrix to Zn anode, where the PVDF layer serves as an elastic H2O/O2‐blocking layer and the decorated TiO2 nanoparticles assist uniform Zn electrodeposition. With this corrosion‐inhibition and electrodeposition‐redirection coating, the electrodeposition consistency and thermodynamic stability of the Zn anode are significantly improved, enabling a long‐term stable plating/stripping performance for 2000 h with an ultralow overpotential (<50 mV) and a high average Coulombic efficiency (>99.4%) for 1000 cycles without obvious dendrite formation. Even at a high current density of 8.85 mA cm−2 with limited Zn supply (DODZn = 60%), stable Zn deposition is achieved over 250 h. When coupled with a MnO2 cathode, the AEC‐Zn anode shows a remarkably enhanced full‐cell cycling stability, indicative of high reliability of aqueous Zn batteries for practical application.
An anti‐corrosion elastic constraint is developed to redirect the Zn electrodeposition for aqueous zinc‐ion batteries. With this corrosion‐inhibition and electrodeposition‐redirection coating, the electrodeposition consistency and thermodynamic stability of Zn anodes are significantly improved, enabling a long‐term stable plating/stripping performance for 2000 h with an ultralow overpotential (<50 mV) and a high Coulombic efficiency (>99.4%) for 1000 cycles.
Zn/H-ZSM-5 catalysts have been frequently investigated for propane dehydrogenation (PDH); however, the active site remains unresolved due to the complexity of the system. We employed in situ FTIR ...spectroscopy and a kinetics method to correlate the Zn speciation and PDH activity in Zn/H-ZSM-5 with two Si/Al ratios (15 and 39) and a range of Zn/Al ratios (0–1.7). Incremental additions of zinc show that Zn2+ sites are preferentially formed on H-ZSM-5 over a fraction of paired Al sites followed by Zn-O-Zn2+ and ZnOH+ sites and then ZnO x clusters. The Zn-OH+ and Zn-O-Zn2+ sites in H-ZSM-5 are more active and selective than isolated Zn2+ for PDH. Zn-OH+ species sublimate over time on stream, leading to catalyst deactivation, while Zn-O-Zn2+ species are stable even after high-temperature reduction (750 °C for 60 min). Three distinct Zn sites (Zn-O-Zn2+, Zn2+, and ZnOH+) show a similar propane reaction order (close to 1) and H2 reaction order (close to 0). Combined with the lack of Zn hydride when propane flows over the catalyst at 550 °C, it is concluded that propane adsorption and dissociation is a rate-determining step and H2 desorption is fast. This work indicates that the preparation of H-ZSM-5 with abundant Al pairs may be a strategy to form stable and selective Zn/H-ZSM-5 catalysts for propane dehydrogenation. It is also highlighted that examining the effect of both metal/Al ratios and Al distribution of the zeolite is crucial in identifying the metal cations in metal–zeolite systems.
Aqueous Zn batteries have drawn tremendous attention for their several advantages. However, the challenges of Zn anodes such as the corrosion and ZnO densification have compromised their application ...in rechargeable Zn‐based batteries. In this paper, a straightforward strategy is employed to facilitate the uniform Zn stripping/plating of the Zn anode through using a ZrO2 coating layer, which contributes to the controllable nucleation sites for Zn2+ and fast Zn2+ transportation through the favorable Maxwell–Wagner polarization. As a result, the low polarization (24 mV at 0.25 mA cm−2), high Coulombic efficiency (99.36% at 20 mA cm−2), and long cycle life (over 3800 h at 0.25 mA cm−2) can be obtained for the ZrO2‐coated Zn anode. It is believed that the ZrO2 coating layer can also act as an inert physical barrier to decrease the contact of the anode and electrolyte, thus reducing both the Zn corrosion and formation of ZnO densification, and then improve the reversibility of Zn anode. The results demonstrated in this work provide an appealing strategy for the future development of rechargeable Zn‐based batteries.
A highly reversible Zn anode is achieved through controllable nucleation sites for Zn2+ and fast Zn2+ transportation under the favorable Maxwell–Wagner polarization, in which a low polarization (24 mV), high Coulombic efficiency (99.36%), and long cycle life (over 3800 h) are obtained by employing a ZrO2‐coating layer.
Crystallography modulation of zinc (Zn) metal anode is promising to promote Zn reversibility in aqueous electrolytes, but efficiently constructing Zn with specific crystallographic texture remains ...challenging. Herein, we report a current‐controlled electrodeposition strategy to texture the Zn electrodeposits in conventional aqueous electrolytes. Using the electrolytic cell with low‐cost Zn(CH3COO)2 electrolyte and Cu substrate as a model system, the texture of as‐deposited Zn gradually transforms from (101) to (002) crystal plane as increasing the current density from 20 to 80 mA cm−2. Moreover, the high current accelerates the Zn nucleation rate with abundant nuclei, enabling uniform deposition. The (002) texture permits stronger resistance to dendrite growth and interfacial side reactions than the (101) texture. The resultant (002)‐textured Zn electrode achieves deep cycling stability and supports the stable operation of full batteries with conventional V/Mn‐based oxide cathodes.
The (002) plane textured Zn metal is realized by using a current‐controlled electrodeposition strategy in a low‐cost Zn (CH3COO)2 aqueous electrolyte. Increasing the current density not only accelerates the Zn nucleation rate with abundant nuclei but also boosts the growth rate of (100) crystal plane, thus enabling the final exposure of (002) surface for Zn electrodeposits.
The rapidly growing demand for wearable and portable electronics has driven the recent revival of flexible Zn‐ion batteries (ZIBs). However, issues of dendrite growth and low the flexibility of Zn ...metal anode still impede their practical application. Herein, 3D nitrogen‐doped vertical graphene nanosheets in situ grown on carbon cloth (N‐VG@CC) are proposed to enable uniform Zn nucleation, thereby obtaining a dendrite‐free and robust Zn anode. The introduced zincopilic N‐containing groups in N‐VG effectively reduce the Zn nucleation overpotential by enhancing the interaction between Zn2+ ion and carbon substrate, as confirmed by density functional theory calculations, thus achieving uniform distribution of Zn nucleus. Moreover, the 3D nanosheet arrays can homogenize electric distribution, which optimizes the subsequence Zn deposition process and realizes the highly reversible Zn plating/stripping process. Consequently, the as‐prepared Zn@N‐VG@CC anode exhibits an improved overall electrochemical performance compared with Zn@CC. As a proof‐of‐concept application, the high‐performance Zn@N‐VG@CC electrodes are successfully employed as anodes for coin and flexible quasi‐solid‐state ZIBs together with MnO2@N‐VG@CC (deposited MnO2 nanosheets on N‐VG@CC) as cathodes. More importantly, the flexible ZIB exhibits impressive cycling stability with 80% capacity retention after 300 cycles and outstanding mechanical flexibility, indicating a promising potential for portable and wearable electronics.
N‐VG nanosheets are in situ grown on CC and used as a 3D Zn plating/stripping scaffold to achieve a dendrite‐free and high‐performance Zn@N‐VG@CC anode. The as‐assemble flexible quasi‐solid‐state ZIB exhibits good electrochemical performance and outstanding mechanical flexibility, indicating promising potential for portable and wearable electronics.
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