Department of Chemistry and Materials Research Institute, The Pennsylvania State University, University Park, PA, 16802, USA.
Angew Chem Int Ed Engl. 2017 Jun 1;56(23):6464-6467. doi: 10.1002/anie.201701087. Epub 2017 May 2.
The ability to selectively form one crystal structure among several options in a polymorphic system is an important goal in solid-state synthesis. Nanocrystal cation exchange, which proceeds rapidly under mild conditions, can retain key structural features and yield otherwise inaccessible phases, but the extent to which crystal structure can be retained and therefore selectively targeted during such reactions has been limited. Here, we show that nanocrystals of digenite Cu S transform to zincblende MnS and CoS upon cation exchange. Zincblende MnS and CoS, which are metastable in bulk, retain both the tetrahedral cation coordination and cubic close packed anion sublattice of digenite Cu S. Comparison with wurtzite MnS and CoS, which have been accessed previously through analogous cation exchange of roxbyite Cu S, demonstrates the selective formation of the related zincblende vs. wurtzite polymorphs by cation exchange of structurally distinct templates.
在多晶体系中，选择性地形成一种晶体结构是固态合成的一个重要目标。在温和条件下快速进行的纳米晶阳离子交换可以保留关键的结构特征，并产生原本无法获得的相，但在这种反应中，晶体结构可以保留并因此具有选择性的程度是有限的。在这里，我们表明，辉铜矿 CuS 的纳米晶在阳离子交换后转化为闪锌矿 MnS 和 CoS。在块状体中处于亚稳状态的闪锌矿 MnS 和 CoS 保留了辉铜矿 CuS 的四面体阳离子配位和立方密堆积阴离子亚晶格。与之前通过罗息比矿 CuS 的类似阳离子交换获得的 wurtzite MnS 和 CoS 进行比较，证明了通过结构不同的模板的阳离子交换，可以选择性地形成相关的闪锌矿与 wurtzite 多晶型物。
