Ledendecker Marc, Paciok Paul, Osowiecki Wojciech T, Pander Marc, Heggen Marc, Göhl Daniel, Kamat Gaurav A, Erbe Andreas, Mayrhofer Karl J J, Alivisatos A Paul
Department of Technical Chemistry I, Technical University Darmstadt, Alarich-Weiss-Straße 8, 64287, Darmstadt, Germany.
Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, Forschungszentrum Jülich GmbH, 52425, Jülich, Germany.
Commun Chem. 2022 Jun 6;5(1):71. doi: 10.1038/s42004-022-00680-w.
Core-shell particles with thin noble metal shells represent an attractive material class with potential for various applications ranging from catalysis to biomedical and pharmaceutical applications to optical crystals. The synthesis of well-defined core-shell architectures remains, however, highly challenging. Here, we demonstrate that atomically-thin and homogeneous platinum shells can be grown via a colloidal synthesis method on a variety of gold nanostructures ranging from spherical nanoparticles to nanorods and nanocubes. The synthesis is based on the exchange of low binding citrate ligands on gold, the reduction of platinum and the subsequent kinetically hindered growth by carbon monoxide as strong binding ligand. The prerequisites for homogeneous growth are low core-binding ligands with moderate fast ligand exchange in solution, a mild reducing agent to mitigate homonucleation and a strong affinity of a second ligand system that can bind to the shell's surface. The simplicity of the described synthetic route can potentially be adapted to various other material libraries to obtain atomically smooth core-shell systems.
具有薄贵金属壳层的核壳颗粒是一类极具吸引力的材料，在从催化到生物医学、制药应用再到光学晶体等各种应用中都具有潜力。然而，合成结构明确的核壳结构仍然极具挑战性。在这里，我们证明了通过胶体合成方法，可以在从球形纳米颗粒到纳米棒和纳米立方体等各种金纳米结构上生长出原子级薄且均匀的铂壳层。该合成基于金上低结合力的柠檬酸盐配体的交换、铂的还原以及随后一氧化碳作为强结合配体的动力学阻碍生长。均匀生长的先决条件是溶液中具有适度快速配体交换的低核结合配体、用于减轻均相成核的温和还原剂以及能够结合到壳表面的第二配体系统的强亲和力。所描述的合成路线的简单性有可能适用于各种其他材料库，以获得原子级光滑的核壳系统。
