Castañeda John, Rogers Blake, Sosa Ysaris, Muñoz Jorge A, Bhattarai Badri, Martinez Ashley M, Phipps M Lisa, Morales Demosthenes P, Montoya Rush Matthew N, Yacaman Miguel José, Montaño Gabriel A, Gibbs John G, Martinez Jennifer S
Department of Applied Physics and Materials Science and Center for Materials Interfaces in Research and Applications (¡MIRA!), Northern Arizona University, 1900 S Knoles Dr, Flagstaff, AZ, 86011, USA.
Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM, 87545, USA.
Small. 2025 Jun;21(25):e2411517. doi: 10.1002/smll.202411517. Epub 2025 May 16.
Microswimmers are self-propelled particles that navigate fluid environments, offering significant potential for applications in environmental pollutant decomposition, biosensing, and targeted drug delivery. Their performance relies on engineered catalytic surfaces. Gold nanoclusters (AuNCs), with atomically precise structures, tunable optical properties, and high surface area-to-volume ratio, provide a new optimal catalyst for enhancing microswimmer propulsion. Unlike bulk gold or nanoparticles, AuNCs may deliver tunable photocatalytic activity and increased catalytic specificity, making them ideal co-catalysts for hybrid microswimmers. For the first time, this study combines AuNCs with TiO/CrO Janus microswimmers, combining the unique properties of both materials. This hybrid system capitalizes on the tuned optical properties of AuNCs and their role as co-catalysts with TiO, driving enhanced photocatalytic performance under ultraviolet (UV) excitation. Using motion analysis, it is shown that the AuNC-microswimmers exhibit significantly greater propulsion and mean squared displacement (MSD) as compared to controls. These findings suggest that the integration of nanoclusters with semiconductor materials enables state of the art, light-switchable microswimmers. These AuNC-microswimmer systems may thus offer new opportunities for environmental catalysis and other applications, providing precise control over catalytic and motile behaviors at the microscale.
微游动体是能在流体环境中自行推进的粒子，在环境污染物分解、生物传感和靶向药物递送等应用方面具有巨大潜力。它们的性能依赖于经过设计的催化表面。具有原子精确结构、可调光学性质和高比表面积的金纳米团簇（AuNCs），为增强微游动体的推进提供了一种新的最佳催化剂。与块状金或纳米粒子不同，AuNCs可以提供可调的光催化活性并提高催化特异性，使其成为混合微游动体的理想助催化剂。本研究首次将AuNCs与TiO/CrO Janus微游动体相结合，融合了两种材料的独特性质。这种混合系统利用了AuNCs的可调光学性质及其作为TiO助催化剂的作用，在紫外（UV）激发下驱动增强的光催化性能。通过运动分析表明，与对照组相比，AuNC-微游动体表现出明显更大的推进力和均方位移（MSD）。这些发现表明，纳米团簇与半导体材料的整合能够实现先进的、光控微游动体。因此，这些AuNC-微游动体系统可能为环境催化和其他应用提供新的机会，在微观尺度上对催化和运动行为进行精确控制。
