Stabilization of Li₇La₃Zr₂O₁₂ Solid Electrolyte through Ga-Based Precipitates and the Ga–Au Surface Layer

Figure 5

Mechanism of Ga–Au interlayer formation on the Li₇La₃Zr₂O₁₂ pellet surface: (a) photographs of the change in the surface color from light yellow to dark gray after 1 h of Au coating; (b) process of coated Au encountering Ga to slowly form an alloy at room temperature; (c) XRD patterns of Au-coated Li₇La₃Zr₂O₁₂ pellets with a Ga concentration of 0 and 0.142; (d) XPS spectrum of Au 4f for Ga-0.142-LLZO; (e) depth profile analysis and (f) XPS spectrum of etching time results of the Au-coated Ga-0.142-LLZO pellet.

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