Nanoparticle clustering in supraparticles to control magnetic long-range interactions

This data publication is based on the metadata and datasets underlying the manuscript: Nanoparticle clustering in supraparticles to control magnetic long-range interactions To tailor superparamagnetic iron oxide nanoparticles (SPIONs) to the specific needs of diverse application fields, it is essential to understand not only their intrinsic properties but also their interactions with each other. Theoretical models predicting/explaining the magnetization behavior of macroscopic samples containing millions of SPIONs are intricate due to the complexity of the underlying relaxation mechanisms in alternating fields. This study introduces supraparticles (SPs) as model architectures to empirically investigate magnetic interactions within and between large SPION clusters (> 100 nanoparticles). For this purpose, nanoparticle dispersions containing SPIONs and silica nanoparticles (SiO2 NPs) as non‐magnetic building blocks are spray‐dried to form binary SPs. Selective salt‐induced agglomeration of the two building block types before spray‐drying is utilized to tailor SP architectures, including control over SPION cluster size, shape, and proximity. Magnetic particle spectroscopy (MPS), operating under ambient conditions, reveals altered magnetization behavior for different cluster structures. Not only the nearest SPION neighbors, but the whole cluster structure up to several micrometers is decisive for the magnetization behavior. This highlights the importance of long‐range magnetic interactions. This work presents a versatile approach for designing model architectures to advance empirical interaction studies between SPIONs in macroscopic samples.本数据集出版物基于下述手稿所依托的元数据与数据集：《超颗粒中的纳米颗粒团簇调控磁长程相互作用》。为使超顺磁性氧化铁纳米颗粒（superparamagnetic iron oxide nanoparticles, SPIONs）适配不同应用领域的特定需求，不仅需要明晰其本征属性，还需掌握其相互间的作用机制。针对包含数百万颗SPIONs的宏观样本，构建可预测、阐释其磁化行为的理论模型极为复杂，这是因为交变磁场下的内在弛豫机制极为繁复。本研究引入超颗粒（supraparticles, SPs）作为模型架构，以实证研究包含100颗以上纳米颗粒的大型SPION团簇内部及团簇间的磁相互作用。为此，研究人员将包含SPIONs与二氧化硅纳米颗粒（silica nanoparticles, SiO₂ NPs，作为非磁性结构基元）的纳米颗粒分散液进行喷雾干燥，以制备二元超颗粒。通过在喷雾干燥前利用盐诱导的选择性团聚作用，可调控两种结构单元的组装方式，从而定制超颗粒的架构，包括SPION团簇的尺寸、形貌与间距。在常温环境下运行的磁颗粒光谱仪（magnetic particle spectroscopy, MPS）结果显示，不同团簇结构的磁化行为存在显著差异。磁化行为的决定性因素不仅包括SPIONs的最近邻相互作用，还涵盖可达数微米尺度的完整团簇结构。这凸显了磁长程相互作用的重要性。本研究提出了一种通用的模型架构设计方法，可推动宏观样本中SPIONs之间相互作用的实证研究。