Atomic Pinning of Trace Additives Induces Interfacial Solvation for Highly Reversible Zn Metal Anodes

Abstract

Aqueous Zn metal batteries are considered promising energy storage devices due to their high energy density and low cost. Unfortunately, such great potential is at present obscured by two clouds called dendrite growth and parasitic reactions. Herein, trace amounts of sodium cyclamate (CYC-Na) are introduced as an electrolyte additive, and accordingly, an atomic-pinning-induced interfacial solvation mechanism is proposed to summarize the effect of trace addition. Specifically, coadsorption of −NH– and −SO3 groups overcomes the ring-flipping effect and pins the CYC anion near the Zn anode surface in parallel, which significantly modifies the Zn2+ solvation sheath at the interface. This process homogenizes the surface Zn2+ flux and reduces the H2O and SO4 2– content on the surface, thus eliminating byproducts and leveling Zn deposition. Cells with trace CYC-Na cycle stably for 3650 h and still cycle for 330 h at high depths of discharge of 56.9%. This work dispels the clouds for efficient trace additives for AZMBs.

Bio-inspired hydroxyl-rich electrolyte additive for highly reversible aqueous Zn-ion batteries with strong coordination chemistry

“…With the import of l -Aa, the cycling life of Zn//Zn symmetric cells at high current density achieves a larger improvement compared with previous results with different additives. 13,14,28,34,54,57–64 The findings presented herein provide compelling evidence that the incorporation of l -Aa can yield a substantial development in the electrochemical reversibility of Zn anodes.…”

The Construction of Anion‐Induced Solvation Structures in Low‐concentration Electrolyte for Stable Zinc Anodes

“…The enhanced current intensities in CV curves reveal the rapider Zn 2 + plating kinetics. [19] Thus, Zn j j Zn symmetric cells with PCAÀ Zn electrolyte display better rate performance and more stable voltage profiles at high rate states in comparison with the case of ZnSO 4 electrolyte (Figure 4b). This characteristics will be beneficial for a planar deposition of Zn 2 + in PCAÀ Zn electrolyte.…”

Rescuing zinc anode–electrolyte interface: mechanisms, theoretical simulations and in situ characterizations

“… 107 In addition, EQCM records a negligible mass change resulting from the adsorption and desorption of H atoms and H 2 O in the pristine electrolyte. 268 …”