Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305-4045, USA.
Nat Mater. 2012 Feb 5;11(3):241-9. doi: 10.1038/nmat3238.
Nanoscience provides many strategies to construct high-performance materials and devices, including solar cells, thermoelectrics, sensors, transistors, and transparent electrodes. Bottom-up fabrication facilitates large-scale chemical synthesis without the need for patterning and etching processes that waste material and create surface defects. However, assembly and contacting procedures still require further development. Here, we demonstrate a light-induced plasmonic nanowelding technique to assemble metallic nanowires into large interconnected networks. The small gaps that form naturally at nanowire junctions enable effective light concentration and heating at the point where the wires need to be joined together. The extreme sensitivity of the heating efficiency on the junction geometry causes the welding process to self-limit when a physical connection between the wires is made. The localized nature of the heating prevents damage to low-thermal-budget substrates such as plastics and polymer solar cells. This work opens new avenues to control light, heat and mass transport at the nanoscale.
纳米科学提供了许多构建高性能材料和器件的策略，包括太阳能电池、热电材料、传感器、晶体管和透明电极。自下而上的制造方法促进了大规模的化学合成，而无需进行浪费材料和产生表面缺陷的图案化和刻蚀工艺。然而，组装和接触工艺仍然需要进一步发展。在这里，我们展示了一种光诱导的等离子体纳米焊接技术，用于将金属纳米线组装成大的互连网络。纳米线连接处自然形成的小间隙可实现有效光聚焦和在需要连接的线点加热。当线之间形成物理连接时，加热效率对结几何形状的极端敏感性会导致焊接过程自限制。加热的局部性质可防止热量损坏低热预算衬底，如塑料和聚合物太阳能电池。这项工作为控制光、热和质量传输开辟了新途径。
