Ulloa José Antonio, Barberá Joaquín, Serrano José Luis
Instituto de Nanociencia y Materiales de Aragón (INMA), Departamento de Química Orgánica, Universidad de Zaragoza-CSIC, C/Pedro Cerbuna 12, 50009 Zaragoza, Spain.
Departamento de Química Orgánica, Facultad de Ciencias Químicas, Universidad de Concepción, Casilla 160-C Concepción, Chile.
ACS Omega. 2020 Dec 22;6(1):348-357. doi: 10.1021/acsomega.0c04662. eCollection 2021 Jan 12.
Monodisperse dendrimer-coated gold nanoparticles with a spherical shape have been obtained by direct reduction of HAuCl with sodium borohydride in the presence of dodecanethiol as a stabilizer and subsequent functionalization by ligand exchange reaction with polybenzylic thiolated dendrons. The substitution pattern of the dendrimeric units plays a fundamental role in the rate of the functionalization exchange process and consequently conditions the size and the polydispersity of the NPs obtained. An ulterior growth process occurs by thermal stimuli (150 °C) in a solvent-free environment. This method, carried out in mild conditions, allows the formation of highly monodisperse gold NPs with different sizes for different time reactions, and we discuss the mechanisms involved in this process. Finally, we demonstrate the chemical composition and stability of our compounds by structural, thermal, and chemical characterization of the samples before and after thermal treatment.
通过在十二烷硫醇作为稳定剂存在的情况下用硼氢化钠直接还原氯金酸，随后通过与聚苯苄基硫醇化树枝状分子进行配体交换反应进行功能化，获得了具有球形形状的单分散树枝状聚合物包覆金纳米颗粒。树枝状单元的取代模式在功能化交换过程的速率中起着基本作用，因此决定了所得纳米颗粒的尺寸和多分散性。在无溶剂环境中通过热刺激（150°C）发生进一步的生长过程。该方法在温和条件下进行，允许在不同的时间反应中形成具有不同尺寸的高度单分散金纳米颗粒，并且我们讨论了该过程中涉及的机制。最后，我们通过对热处理前后样品的结构、热和化学表征来证明我们化合物的化学成分和稳定性。
