Invited for this month's cover is the group of Michael Ruck and Thomas Doert at the Technische Universität Dresden (Germany). The cover picture shows the transformation of a Bi‐Ni core‐shell particle into a homogenous intermetallic BiNi particle. To understand the mechanism for the BiNi formation in the polyol process, various methods such as X‐ray and electron diffraction, HR‐TEM, mass spectrometry and FT‐IR spectroscopy were employed. In a microwave‐assisted one‐pot synthesis at first Bi‐particles emerge by reduction of a Bi‐salt. The reduction of the Ni‐salt most likely occurs on the surface of these particles, followed by a complete encasement of the Bi‐core (blue) with a shell of Ni‐particles (green). As the reaction continues, the Ni‐atoms diffuse into the Bi‐core until the homogeneous BiNi particle is attained. Read the full text of their Full Paper at 10.1002/open.202000236.

中文翻译：

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微波辅助多元醇工艺中 Bi-Ni 相的形成机制

本月封面受邀的是德累斯顿工业大学（德国）的 Michael Ruck 和 Thomas Doert 小组。封面图片显示了 Bi-Ni 核壳粒子向均质金属间化合物 BiNi 粒子的转变。为了了解多元醇过程中 BiNi 形成的机制，采用了各种方法，例如 X 射线和电子衍射、HR-TEM、质谱和 FT-IR 光谱。在微波辅助一锅法合成中，首先通过还原双盐产生双粒子。镍盐的还原最有可能发生在这些颗粒的表面，然后是双核（蓝色）被镍颗粒（绿色）的外壳完全包裹。随着反应的继续，Ni 原子扩散到 Bi 核中，直到获得均匀的 BiNi 颗粒。