Recent Advances and Prospects of Cathode Materials for Rechargeable Aqueous Zinc‐Ion Batteries

Abstract

attention. [9][10][11] AZIBs are considered as one of the most ideal candidates for largescale energy storage owing to their following advantages:i) The excellent properties of zinc: According the data in Table 1, the abundance of zinc in the earth's crust is 79 ppm, and ranks fourth in the world metal production, so zinc has a low market price. Zn metal anode has good electrical conductivity (5.91 µΩ cm), high volumetric energy density (5851 mAh cm −3 ), high theoretical capacity (819 mAh g −1 ), and relatively low redox potential (−0.76 V vs standard hydrogen electrode) which is more suitable in aqueous solution. In addition, multivalent zinc ion can transfer two electrons to facilitate more energy storage than the univalent batteries. [12] At the same time, the ionic radius of zinc ions is 0.74 Å, which is smaller than that of sodium ions (1.02 Å) and close to that of lithium ions (0.69 Å). Moreover, zinc is the essential trace element for human body. [9] In brief, Zn has the superiorities of low cost, low-toxicity, abundant resource, easily recycle, and environmental friendliness.ii) The higher ionic conductivity and safety of aqueous electrolytes: The aqueous electrolytes offer two orders of higher magnitude ionic conductivities (≈1 S cm −1 ) than that of organic electrolytes (≈10 −2 -10 −3 S cm −1 ), so aqueous battery usually has higher power density. [3,13] Meanwhile, the organic electrolytes are usually toxic and flammable, while the aqueous electrolytes are nontoxic and safe, which can mitigate the environmental disruption and recycling costs. iii) The facile assembly process: AZIBs can be assembled in the air condition owing to the stability of zinc anode and aqueous electrolyte. Compared with the batteries assembled in the inert-gas glove box, the manufacturing costs of ZIBs are greatly reduced. The facile manufacture and recycling of AZIBs is an important advantage in the large-scale storage applications.Combining the above advantages, low-cost, safe, and green next-generation AZIBs are suitable specifically for large-scale stationary storage applications. So far, AZIBs are still at the infancy stage. The related researches mainly focused on cathode materials. We count the publication numbers of the reported cathodes for AZIBs in the period from 2012 to February 2019 (1, Supporting Information). As illustrated in Figure 1a, the number of annual publications on cathodes for AZIBs continues to increase rapidly in the recent years. However, in the preliminary stage, Electrochemical energy storage devices will definitely play a vital role in the future energy landscape of the world. The innovation of electrode materials is a key task for the breakthrough of present bottleneck faced by electrochemical energy storage devices. Aqueous zinc-ion batteries (AZIBs) are gaining rapid attention, and they offer tremendous opportunities to explore the low-cost, safe, and next-generation green batteries for large-scale stationary storage applications. In this review, the authors aim to give a comprehensive overview ...

Defect Engineering in Manganese‐Based Oxides for Aqueous Rechargeable Zinc‐Ion Batteries: A Review

“…As such, in the recent years, researchers have been exploring various materials that can potentially work as the ZIB cathodes. [ 23–25 ]…”

Latest Advances in High-Voltage and High-Energy-Density Aqueous Rechargeable Batteries

“…[65]. Copyright 2019, American Chemical Society materials [73][74][75][76][77][78][79][80][81][82][83][84][85][86]. Here, we summarize the recent progress on zinc-based batteries with high voltage and high energy density.…”

2020 Roadmap on Zinc Metal Batteries

“…Several scientific challenges including the dendrite growth and corrosion of Zn anode, the dissolution and failure of cathode materials, the strong electrostatic interactions with the host matrix, the byproducts formation, as well as the absence of new electrolyte, commonly cause sluggish diffusion, low coulombic efficiency (CE), poor lifespan, or inferior Zn-storage capability. [36,37,41,42] Currently, the lack of suitable cathode materials hampers the further development of AZIBs to a great extent. Recently, most research scholars focused on Mn-based cathodes, Mo-based cathodes, V-based cathodes, Prussian blue analogs, organics and some other materials.…”

“…• nH 2 O and other oxides are employed as the cathodes for AZIBs. [36,37,41] Unfortunately, the cathodes without the modification or treatment usually show unsatisfactory energy densities and sluggish reaction kinetics, suffer from severe structural failure and dissolution of the components in the charging/discharging process. At present, the innovation of electrode materials is one of the vital tasks for AZIBs.…”