Long cyclic stability of acidic aqueous zinc-ion batteries achieved by atomic layer deposition: the effect of the induced orientation growth of the Zn anode

Zn anodes are advantageous for use in rechargeable aqueous zinc ion batteries (ZIBs) because of their high theoretical specific capacities, low redox potentials, and safety. However, Zn anodes have several challenges, such as easy corrosion and uncontrollable zinc dendrite growth, which deteriorate the longterm cycling capability and, thus, badly hinder the practical applications of ZIBs. This study demonstrates a highly reversible and stable Zn anode by constructing a positive fully conjugated porous organic polymer-based (TM−OH) multifunctional protective layer. This TM−OH-based layer can provide a stable and corrosion-resistant "wall" with fine electrolyte wettability simultaneously, which is due to the fully conjugated structure and abundant hydrophilic OH. Moreover, Zn deposits of TM−OH@ Zn display horizontally rather than upright dendrite, which is probably attributed to interaction between triazine rings rich of lone pair electrons and Zn 2+ . Consequently, the TM−OH@Zn electrode shows ultralow voltage hysteresis (25, 28 mV at 0.1, 1 mA cm −2 in a symmetric cell, respectively), highly reversible stripping/plating behavior, and excellent cycling stability (good operation even after 1200 h at 0.1 mA cm −2 , 0.05 mAh cm −2 in a symmetric cell). TM−OH@Zn//MnO 2 ZIBs were fabricated and exhibited better comprehensive electrochemical performance than Zn//MnO 2 ZIBs, demonstrating the potential practical application of TM− OH@Zn.

Section: Resultssupporting

confidence: 66%

Section: Introductionmentioning

confidence: 99%

Highly Reversible and Stable Zinc Anode Enabled by a Fully Conjugated Porous Organic Polymer Protective Layer

Wang

Sun

et al. 2022

“…As one of the most accurate surface-coating methods, atomic layer deposition (ALD) has been widely applied to solve the interfacial issues of the electrodes in various battery systems. − For the cathode protection in ZIBs, the ultrathin ALD layer with controllable thickness would not only protect the electrode from the undesirable side reaction at the interface to inhibit the cathode dissolution but also act as the artificial cathode electrolyte interphase to allow the transference of zinc ions. Guo et al first reported an atomic layer-deposited HfO 2 protective layer on the Zn 3 V 2 O 7 (OH) 2 ·2H 2 O cathode as an artificial solid electrolyte interphase .…”

Section: Introductionmentioning

confidence: 99%

Atomic Layer-Deposited ZnO Layer on Hydrated Vanadium Dioxide Cathodes against Vanadium Dissolution for Stable Zinc Ion Batteries

2022

Vanadium oxides are considered one of the most promising cathode materials for aqueous zinc ion batteries. However, vanadium dissolution caused by undesirable side reactions greatly decreases the structure stability and capacity retention. In this work, an atomic layer-deposited ZnO layer is uniformly coated on a hydrated vanadium dioxide nanosheet array cathode, which effectively suppresses the vanadium dissolution and side reactions. The resultant cathode displays improved capacity retentions from 74 to 89% after 100 cycles at 0.5 A g −1 and from 29 to 71% after 990 cycles at 5 A g −1 . Moreover, the structural evolution after electrochemical cycling of the cathode is thoroughly investigated to reveal the protection mechanism. The atomic layer deposition strategy may also be extended to the protection of other cathodes that suffer from the dissolution issue with wide choices of the protection layer materials.

“…Considering the effect of the surface atomic structure, the zinc corrosion and H 2 evolution could be effectively weakened. As a consequence, the induced exposure of the zinc (002) plane would be beneficial for the reversibility and stability of the zinc anode. − Graphene, with a hexagonal lattice structure, is reported to be effective in driving deposition of the (002) plane because of the small lattice mismatch (7.4%). The resultant epitaxial Zn anode presents superior reversibility (CE exceeding 99.7%) over thousands of cycles .…”

Section: Introductionmentioning

confidence: 99%

Directing the Preferred Crystal Orientation by a Cellulose Acetate/Graphene Oxide Composite Separator for Dendrite-Free Zn-Metal Anodes

Luo

Yang

Tao

et al. 2021

The issue of degraded reversibility of zinc-metal anodes resulting from dendrite formation and surface-originated side reactions is still a fundamental challenge for high-performance zinc-ion batteries (ZIBs). Herein, a graphene oxide (GO) nanosheet-modified cellulose acetate (CA) separator is developed with an ultralow mass loading of 4 μg cm −2 by a simple and lowcost filtration method. The low lattice mismatch of GO with Zn metal and numerous hydrophilic O-containing groups of GO enable the uniform Zn nucleation and the following epitaxial electrodeposition along the (002) plane, leading to a dendrite-free surface. Significantly, the surface chemistry of GO is important as the hydrophilic O-containing groups act as the initial nuclei deposition sites, which would grow larger along the parallel direction in the subsequent process. This CA/GO composite separator elevates the symmetric cell lifespan to 500 h at a high current density of 10 mA cm −2 (1 mA h cm −2 ). Moreover, a smaller nucleation overpotential (89 mV at 1 mA cm −2 ) and excellent Coulombic efficiency (higher than 96%) can also be realized. Furthermore, such a separator engineering enables an improved cycling performance for hydrated VO 2 /CC||Zn batteries. This separator modification method provides a pathway for the development of high-performance ZIBs and expands their application in other metal-related energy devices suffering from irreversibility.