Camacho Guillermo, de Vicente Juan
F2N2Lab, Magnetic Soft Matter Group, Department of Applied Physics, Faculty of Sciences, University of Granada, C/Fuentenueva s/n, Granada 18071, Spain.
ACS Nano. 2025 Aug 12;19(31):28873-28887. doi: 10.1021/acsnano.5c09450. Epub 2025 Jul 30.
Speeding up the directed self-assembly of functional nanomaterials is a rapidly advancing area of research. Traditional self-assembly methods can be slow and limited by kinetic barriers. In this study, we demonstrate that the process can be dramatically accelerated for magnetic colloids when biaxial toggled magnetic fields (BTFs) are used. In this field configuration, a transversal pulsed magnetic field is superimposed perpendicular to the primary toggled magnetic field, facilitating faster phase separation in a model magnetic colloid. This approach offers enhanced control over aggregation dynamics by adjusting the field's frequency and intensity and does not require any physical templates. Beyond structure control, the aggregation kinetics can also be precisely tuned. Within the context of magnetic materials, this method enables the formation of diverse and tunable structures such as chains, columns, depercolated aggregates, and percolating bands. BTFs further promote the formation of highly crystalline domains, enhancing the properties of the resulting self-assembled materials. While this technique is specifically tailored for magnetic systems, its versatility makes it relevant for the design and fabrication of functional nanomaterials. The ability to tune aggregation kinetics and achieve a range of structures may be beneficial for applications in photonics, electronics, and biomedicine.
加速功能纳米材料的定向自组装是一个快速发展的研究领域。传统的自组装方法可能速度缓慢且受动力学障碍限制。在本研究中，我们证明，当使用双轴翻转磁场（BTF）时，磁性胶体的自组装过程可以显著加速。在这种场配置中，横向脉冲磁场垂直于主翻转磁场叠加，促进了模型磁性胶体中更快的相分离。这种方法通过调整场的频率和强度，对聚集动力学提供了更好的控制，并且不需要任何物理模板。除了结构控制外，聚集动力学也可以精确调整。在磁性材料的背景下，这种方法能够形成各种可调谐结构，如链、柱、去渗流聚集体和渗流带。BTF进一步促进了高度结晶域的形成，增强了所得自组装材料的性能。虽然这项技术是专门为磁性系统量身定制的，但其通用性使其与功能纳米材料的设计和制造相关。调整聚集动力学并实现一系列结构的能力可能对光子学、电子学和生物医学应用有益。
