Multifunctional MXene‐Bonded Transport Network Embedded in Polymer Electrolyte Enables High‐Rate and Stable Solid‐State Zinc Metal Batteries

Abstract

Sluggish transport kinetics and unstable electrode-electrolyte interface are the main obstacles that greatly impair the electrochemical performance of solid-state Zn metal batteries. Herein, the concept of multifunctional MXene bonded transport network-embedded poly(vinylidene fluoride co-hexafluoropropylene)/Zn(OTf ) 2 solid polymer electrolyte (PH/MXene SPE) is proposed as "all-in-one" strategy for designing robust SPE. In order to uncover the mechanism of such rational designed SPE on regulating the ion transport, as well as the interphase chemistry and Zn deposition, comprehensive research including density functional theory calculation, simulation, and multiple characterization techniques are carried out. As the results indicate, the formation of hydrogen bond network between the MXene nanofiller and PH polymer benefits fast and homogeneous ion transport. Then, the in situ formation of stable organic/inorganic hybrid interphase is capable to ensure the efficient interfacial transport kinetics and uniform Zn deposition. When such PH/ MXene SPE is applied, ultrastable Zn plating/stripping behavior with small polarization voltage can be realized. In addi, solid-state Zn/VO 2 batteries with significantly improved rate performance and cyclic stability also can be demonstrated. The unique strategy proposed in this study offer a new insight into SPE design and the development of high-performance solid-state Zn metal batteries.

A Theory‐Driven Complementary Interface Effect for Fast‐Kinetics and Ultrastable Zn Metal Anodes in Aqueous/Solid Electrolytes

“…Note that the VO 2 cathode material was synthesized by a simple hydrothermal method (Figure S28, Supporting Information), [ 54 ] the polymer electrolyte (Figure 7f) was prepared by the method reported previously. [ 55 ] As depicted in Figure 7g, the DIM Zn anode‐based solid‐state batteries can keep a discharge capacity of 225.4 mA h g −1 after 700 cycles at 0.5 A g −1 , while the Pure Zn‐based one would sharply decay in the initial cycles and only remain a specific capacity of 71.9 mA h g −1 after 395 cycles. While for the rate performance (Figure 7h), it is obvious that the high‐rate storage capability of modified system also can be greatly improved.…”

Dendrite-Free and Highly Stable Zn Metal Anode with BaTiO3/P(VDF-TrFE) Coating

“…Benefiting from the high dielectric constant, the ions' transport kinetics through the BTO/PVT coating layer can be facilitated. 37 In the FTIR spectra of BaTiO 3 and α-BaTiO 3 (Figure S9), the stronger peak located at around 1633 cm −1 in α-BaTiO 3 is attributed to the stretching mode of OH, confirming that the surface of BaTiO 3 was modified by OH groups. 38 For the BTO/PVT film (Figure 1c), the typical vibration peaks at 848, 887, and 1182 cm −1 are attributed to the β-crystalline structure of P(VDF-TrFE).…”

“…The BTO/PVT film exhibits a higher dielectric constant than that of pristine PVT film due to the incorporation of BTO nanoparticles (Figure S8). Benefiting from the high dielectric constant, the ions’ transport kinetics through the BTO/PVT coating layer can be facilitated . In the FTIR spectra of BaTiO 3 and α-BaTiO 3 (Figure S9), the stronger peak located at around 1633 cm –1 in α-BaTiO 3 is attributed to the stretching mode of OH, confirming that the surface of BaTiO 3 was modified by OH groups .…”

Advances in functional organic material-based interfacial engineering on metal anodes for rechargeable secondary batteries

“…22a. 201 The designed PH/MXene-SPE improved the cycling performance of the Zn|PH/MXene-SPE|Zn symmetric cell for over 2500 h (Fig. 22b), which was attributed to the enhanced ionic conductivity and regulated the interphase chemistry and Zn deposition.…”