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The surface feature of solid electrolytes fundamentally governs their own physical properties and significantly affects the interaction with the electrode materials. The evaluation of interfacial contact between the electrolyte and the metallic anode is largely relied on the macroscopic contact angle measurement, which is influenced by the intrinsic wettability and the microstructure of the electrolyte. In this work, the surface chemistry of the solid electrolyte is first regulated via facile thermal treatments. Then, scanning probe microscopy (SPM)-based techniques are comprehensively adopted to study the interaction between the electrolyte and metallic anode at the nanoscale. By manipulating the overpotential applied on the SPM tip, the mobile sodium ions at the subsurface of the solid electrolyte can be extracted toward the surface, and the eventual topography of the products is deliberately correlated with the sodium wettability. In this context, the impact of surface treatment on the sodium wettability of the surface layer is systematically evaluated based on the topographic evolution at the nanoscale. Furthermore, the local electrochemical reaction dynamics is revealed by correlating the surface ionic activity and current-voltage (I-V) curves. This work presents a new methodology to effectively evaluate the sodium wettability of the solid electrolyte, and these findings can provide meaningful implications to the surface engineering of ceramic electrolytes for high-performance solid-state batteries.

Dendrite growth under large current density is the key intrinsic issue impeding a wider application of Li metal anodes. Previous studies mainly focused on avoiding dendrite growth by building an additional interface layer or surface modification. However, the mechanism and factors affecting dendrite growth for Li metal anodes are still unclear. Herein, we analyze the causes for dendrite growth, which leads us to suggest three-dimensional (3D) metal anodes as a promising approach to overcome the dendrite issues. A 3D composite Li anode was prepared from renewable carbonized wood doped with Sn to demonstrate its superior electrochemical performance compared with Li foils. The anode was cycled at various current densities from 0.1 to 10 mA cm-2 for five cycles at each current density, displaying low overpotential compared with conventional Li foils. Long galvanostatic cycling at 1 mA cm-2 for 1000 h and at 2 mA cm-2 for 500 h was achieved without dendrite growth. Further analysis reveals that the 3D structure facilitates surface diffusion by increasing the surface area from 5.23 × 10-3 m2 g-1 (Li foil) to 2.64 m2 g-1 and by creating nanoscale separation walls. The tin alloying effectively prevents non-uniform lithium plating by creating abundant nucleation centers. Additionally, suitable alloying elements for a wider range of 3D Li anodes have been identified from density functional theory calculations.

All-solid-state lithium metal batteries (ASSLiMB) have been considered as one of the most promising next-generation high-energy storage systems that replace liquid organic electrolytes by solid-state electrolytes (SSE). Among many different types of SSE, NASICON-structured Li1+ xAl xGe2- x(PO3)4 (LAGP) shows high a ionic conductivity, high stability against moisture, and wide working electrochemical windows. However, it is unstable when it is in contact with molten Li, hence largely limiting its applications in ASSLiMB. To solve this issue, we have studied reaction processes and mechanisms between LAGP and molten Li, based on which a failure mechanism is hence proposed. With better understanding the failure mechanism, a thin thermosetting Li salt polymer, P(AA- co-MA)Li, layer is coated on the bare LAGP pellet before contacting with molten Li. To further increase the ionic conductivity of P(AA- co-MA)Li, LiCl is added in P(AA- co-MA)Li. A symmetric cell of Li/interface/LAGP/interface/Li is prepared using molten Li-Sn alloy and galvanically cycled at current densities of 15, 30, and 70 μA cm-2 for 100 cycles, showing stable low overpotentials of 0.036, 0.105, and 0.257 V, respectively. These electrochemical results demonstrate that the interface coating of P(AA- co-MA)Li can be an effective method to avoid an interfacial reaction between the LAGP electrolyte and molten Li.

Dabrafenib is a novel targeted antimelanoma drug. The present work explored the binding mechanism of dabrafenib-human serum albumin (HSA) and the effect on the esterase-like activity and antioxidant activity of HSA by using 19F NMR, spectroscopy methods, and molecular dynamics simulation. The results of 19F NMR, fluorescence, and time-resolved fluorescence spectroscopy revealed that dabrafenib spontaneously binds to the subdomain IIIA of the HSA by hydrophobic action and forms a static complex. The binding affects the esterase-like activity of HSA but not its antioxidant activity. According to the results of molecular dynamics simulation, dabrafenib interacts with Arg410 and Tyr411, which are the key residue associated with the esterase-like activity of HSA. Meanwhile, dabrafenib does not interact with Cys34, the key residue associated with the antioxidant activity of HSA. The results of circular dichroism spectroscopy and molecular dynamics simulation show that the conformation of HSA is not affected by the binding of dabrafenib. This study can provide useful information for understanding the pharmacokinetic properties of dabrafenib.