Fluoride shuttle batteries (FSBs), which utilize defluorination of metal fluorides and fluorination of the resultant metals, are expected to have high energy densities. In situ Raman microscopy was conducted during FSB reactions of a nearly‐2D cluster of orthorhombic BiF₃ microparticles partly embedded in a gold‐plated film (o‐BiF₃/gold). At a high overpotential, defluorination of the surface of an o‐BiF₃ particle (or cluster) was almost completed within approximately 120 s. At a low over potential, defluorination proceeded from the contours of the cluster that was in contact with the gold to the center of the cluster, suggesting that the rate‐limiting process was electronic diffusion. Conversely, fluorination proceeded uniformly at the surface of the cluster to form BiF₃ with a cubic structure (c‐BiF₃). The results will lead to the establishment of a strategy for efficient use of active materials with low electronic and ionic conductivities.

中文翻译：

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原位拉曼显微镜研究BiF3团簇表面氟化物穿梭电池反应的演变

利用金属氟化物的脱氟和所得金属的氟化的氟化物穿梭电池（FSB）有望具有高能量密度。在部分嵌入镀金膜（o-BiF ₃ /金）中的近2D正交晶体BiF ₃微粒的FSB反应期间，进行了原位拉曼显微镜检查。在高电势下，o-BiF ₃的表面脱氟粒子（或簇）几乎在约120 s内完成。在低电位下，脱氟作用是从与金接触的团簇轮廓开始到团簇的中心，这表明限速过程是电子扩散。相反地，氟化在集群的表面均匀进行，以形成BIF ₃具有立方结构（C-BIF ₃）。结果将导致建立有效使用电子和离子电导率低的活性材料的策略。