Jenewein Christian, Avaro Jonathan, Appel Christian, Liebi Marianne, Cölfen Helmut
Department of Chemistry, Physical Chemistry, University of Konstanz, Universitätsstrasse 10, Konstanz, Germany.
Center for X-ray Analytics, Empa-Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014, St. Gallen, Switzerland.
Angew Chem Int Ed Engl. 2022 Jan 10;61(2):e202112461. doi: 10.1002/anie.202112461. Epub 2021 Nov 25.
Binary mesocrystals offer the combination of nanocrystal properties in an ordered superstructure. Here, we demonstrate the simultaneous self-assembly of platinum and iron oxide nanocubes into micrometer-sized 3D mesocrystals using the gas-phase diffusion technique. By the addition of minor amounts of a secondary particle type tailored to nearly identical size, shape and surface chemistry, we were able to promote a random incorporation of foreign particles into a self-assembling host lattice. The random distribution of the binary particle types on the surface and within its bulk has been visualized using advanced transmission and scanning electron microscopy techniques. The 20-40 μm sized binary mesocrystals have been further characterized through wide and small angle scattering techniques to reveal a long-range ordering on the atomic scale throughout the crystal while showing clear evidence that the material consists of individual building blocks. Through careful adjustments of the crystallization parameters, we could further obtain a reverse superstructure, where incorporated particles and host lattice switch roles.
二元介晶在有序超结构中兼具纳米晶体的特性。在此，我们展示了利用气相扩散技术将铂纳米立方体和氧化铁纳米立方体同时自组装成微米级三维介晶。通过添加少量尺寸、形状和表面化学性质几乎相同的第二种粒子类型，我们能够促使外来粒子随机掺入自组装主体晶格中。利用先进的透射电子显微镜和扫描电子显微镜技术，已观察到二元粒子类型在表面和内部的随机分布。通过广角和小角散射技术对尺寸为20 - 40μm的二元介晶进行了进一步表征，以揭示整个晶体在原子尺度上的长程有序性，同时清楚地表明该材料由单个结构单元组成。通过仔细调整结晶参数，我们还能进一步获得一种反向超结构，其中掺入的粒子和主体晶格互换了角色。
