Recently, Professor Zhou Jiang and Associate Professor Cao Xinxin of Central South University used the method of constructing disordered zinc silicate (ZSO) in situ on zinc foil as an artificial solid electrolyte interface layer to achieve rapid transmission of Zn2+ and highly reversible Zn plating/peeling.
On September 20, 2022, the study was published in the journal Matter under the title “Constructing fast-ion-conductive disordered interphase for high-performance zinc-ion and zinc-iodine batteries.”
Water-based rechargeable zinc-based batteries are the most promising grid-scale energy storage devices due to their inherent safety, cost efficiency, and ease of manufacturing. However, the severe problem of Zn2+ transmission instability at the zinc dendrite and electrode/electrolyte interface has been a major obstacle to the commercialization of aqueous zinc-based batteries. In view of this, the in situ formation of an artificial solid electrolyte interface as a direct protection scheme can improve the magnification performance of the Zn anode by shortening the Zn2+ diffusion distance. More importantly, the disordered interface phase exhibits the great advantages of rapid diffusion of Zn2+ due to the elimination of internal grain boundaries. Therefore, it is of great significance to the study of stabilizing the negative electrode of zinc metal by designing an artificial solid electrolyte interface dominated by amorphous disordered regions for rapid ion transport and highly reversible zinc stripping/plating, and constructing a reconstructed nanodomain with rich isotropic properties as a reasonable strategy for simultaneous dendrite inhibition and self-regulation of Zn2+ transport.
Recently, Professor Zhou Jiang, Associate Professor Cao Xinxin and others of Central South University used the method of constructing disordered zinc silicate (ZSO) in situ on zinc foil as an artificial solid electrolyte interface layer, which has a high Zn2+ conductivity (9.29 mS·cm-1) and a rich ion diffusion channel, thereby achieving Zn2+ fast transmission and highly reversible Zn plating/stripping, and redistributing Zn2+ flux to guide uniform Zn deposition to achieve dendrite-free Zn metal anode.
This strategy ensures that the symmetrical battery can be reversibly deposited/peeled (with a life of more than 2500 hours), which can provide Zn@ZSO a specific capacity of 336.8 mAh g-1 at 0.2 A g-1 at 0.2 A g-1 and a capacity retention rate of 90.1% at 5 A g-1 after 1000 cycles; At the same time, when it is applied to zinc iodine batteries, it can retain 97.98% of the capacity after 60 h by inhibiting I3-diffusion to the Zn metal surface. The interface design provides inspiration for accelerating the commercialization of high-performance zinc-based batteries.
Figure 1: ZSO interface layer structure characterization. The self-modulation transmission of Zn2+ is achieved by constructing a large number of isotropic nanoscale Zn2+ diffusion channels by in situ strategy, and finally the deposition morphology shown in Figure a is obtained.
Figure 2: Electrochemical properties of the Zn@ZSO electrode. The construction of the ZSO interface layer improves the coulomb efficiency and magnification performance of the Zn electrode. The surface chemistry analysis of the electrode during deposition/peeling showed the stability of the interfacial layer, as well as the formation of an electron-rich Si environment due to the continuous bonding of Zn-O-Si during the deposition process and the continuous negative shift of the binding energy of Si(-O)2 and Si(-O)3 binding energy as Zn2+ transmission.
Figure 3: Zn peeling/plating mechanism of Zn@ZSO anode. The results of ion mobility coefficient and conductivity test show that the ZSO interface layer has rapid Zn2+ diffusion ability and good Zn2+ conductivity. The electric field and Zn2+ concentration field simulations confirm that the ZSO interface layer homogenizes the electric field on the surface of the Zn electrode and has a large number of Zn2+ transmission channels.
Figure 4: Electrochemical properties of Zn//NH4V4O10 and Zn@ZSO//NH4V4O10 batteries.
Figure 5: Electrochemical performance of Zn@ZSO//Zn@ZSO symmetrical batteries in a mixed electrolyte of 2 M ZnSO4 and 0.05 M KI.
Zn@ZSO electrode exhibits good electrochemical behavior in both the 2 M ZnSO4 and 2 M ZnSO4+0.05 KI mixed electrolytes. Full battery performance tests show that Zn@ZSO//NH4V4O10 batteries have a smaller battery overpotential and improved battery cycle life; The Zn@ZSO electrode exhibited better plating/stripping life than that in the 2 M ZnSO4+0.05 KI mixed electrolyte, and the Zn@ZSO//I2 performance test results confirmed the effectiveness of the ZSO interface layer in inhibiting the reaction of polyiodes and Zn metals and the feasibility of long-term stable operation of the battery. (Source: Science Network)
Related paper information:https://doi.org/10.1016/j.matt.2022.08.025