Magnetically controlled anisotropic light emission of DNA-functionalized supraparticles

• Published in: MRS bulletin 2022-11, Vol.47 (11), p.1084-1091
• Main Authors: Erdem, Talha, Zupkauskas, Mykolas, O’Neill, Thomas, Cassiagli, Alessio, Xu, Peicheng, Altintas, Yemliha, Mutlugun, Evren, Eiser, Erika
• Format: Article
• Language: English
• Subjects: Active control; Anisotropy; Applied and Technical Physics; Block copolymers; Characterization and Evaluation of Materials; Chemical synthesis; Chemistry and Materials Science; Displays; Emissions control; Energy Materials; Impact Article; Indium phosphides; Iron oxides; Light; Light emission; Magnetic fields; Materials Engineering; Materials Science; Nanomaterials; Nanoparticles; Nanotechnology; Plasmonics; Polarization; Polarized light; Polarizers; Quantum dots; Self-assembly; Silver; Zinc sulfide
• ISSN: 0883-7694; 1938-1425
• DOI: 10.1557/s43577-022-00352-z

In this article, we show the DNA-functionalization of supraparticles, form their network, and manipulate the optical features of these networks by applying a magnetic field. We start with preparing the supraparticles (SPs) of semiconducting InP/ZnSeS/ZnS quantum dots (QDs), plasmonic silver nanoparticles, and superparamagnetic iron oxide nanoparticles. These SPs are prepared by employing azide-functionalized amphiphilic diblock or triblock copolymers as well as by using their combinations. Subsequently, we attached single-stranded DNAs to these SPs by employing copper-free click chemistry. Next, we hybridized DNA-coated QD SPs with the iron oxide SPs and formed a network. By applying a magnetic field, we restructured this network such that the iron oxide SPs are aligned. This led to an anisotropic emission from the QD SPs with a polarization ratio of 1.9. This study presents a proof-of-concept scheme to control the optical features of a self-assembled supraparticle system using an external interaction. We believe that our work will further contribute to the utilization of smart self-assembly techniques in optics and photonics. Impact statement The self-assembly of the nanoparticles, which lies at the heart of this article, enables achieving unconventional physical responses that cannot be obtained by the individual nanomaterials. Therefore, controlling the self-assembly process can lead to unprecedented control over the mechanical, optical, or electronic features of such novel architectures made of various types of nanoparticles. This smart self-assembly process will undoubtedly enable the realization of novel applications and open new avenues in materials science and engineering. In this article, we employ the self-assembly in two different aspects. First, we self-assembled magnetic, plasmonic, and semiconducting nanoparticles to obtain their supraparticles with the help of various amphiphilic polymers. Next, single-stranded DNA molecules were attached to them for the first time to achieve a precise control over their physical forming a “network of supraparticles of nanoparticles.” As a proof-of concept demonstration, we hybridized DNA-functionalized magnetic supraparticles made of iron oxide nanoparticles and DNA-functionalized light-emitting supraparticles containing InP/ZnSe/ZnS quantum dots. We explored the potential of tailoring the emission characteristics of the emitted light by utilizing an external magnetic field. We observed that under an extern