Lüdicke Malín G, Hildebrandt Jana, Schindler Christoph, Sperling Ralph A, Maskos Michael
Fraunhofer Institute for Microengineering and Microsystems IMM, 55129 Mainz, Germany.
Federal Institute for Materials Research and Testing, 12205 Berlin, Germany.
Nanomaterials (Basel). 2022 Jun 9;12(12):1983. doi: 10.3390/nano12121983.
The separation of colloidal nanocrystals from their original synthesis medium is an essential process step towards their application, however, the costs on a preparative scale are still a constraint. A new combination of approaches for the purification of hydrophobic Quantum Dots is presented, resulting in an efficient scalable process in regard to time and solvent consumption, using common laboratory equipment and low-cost materials. The procedure is based on a combination of solvent-induced adhesion and solid phase extraction. The platform allows the transition from manual handling towards automation, yielding an overall purification performance similar to one conventional batch precipitation/centrifugation step, which was investigated by thermogravimetry and gas chromatography. The distinct miscibility gaps between surfactants used as nanoparticle capping agents, original and extraction medium are clarified by their phase diagrams, which confirmed the outcome of the flow chemistry process. Furthermore, the solubility behavior of the Quantum Dots is put into context with the Hansen solubility parameters framework to reasonably decide upon appropriate solvent types.
从原始合成介质中分离胶体纳米晶体是其应用的一个关键工艺步骤，然而，制备规模的成本仍是一个限制因素。本文提出了一种用于纯化疏水性量子点的新方法组合，使用普通实验室设备和低成本材料，在时间和溶剂消耗方面实现了高效可扩展的工艺。该方法基于溶剂诱导粘附和固相萃取的结合。该平台允许从手动操作向自动化转变，产生与一个传统批次沉淀/离心步骤相似的整体纯化性能，通过热重分析和气相色谱对其进行了研究。用作纳米颗粒封端剂的表面活性剂、原始介质和萃取介质之间明显的混溶间隙通过它们的相图得以阐明，这证实了流动化学过程的结果。此外，将量子点的溶解行为与汉森溶解度参数框架相结合，以合理确定合适的溶剂类型。
