Catone D, Ciavardini A, Di Mario L, Paladini A, Toschi F, Cartoni A, Fratoddi I, Venditti I, Alabastri A, Proietti Zaccaria R, O'Keeffe P
Division of Ultrafast Processes in Materials (FLASHit) , Istituto di Struttura della Materia-CNR (ISM-CNR) , 100 Via del Fosso del Cavaliere , 00133 Rome , Italy.
Division of Ultrafast Processes in Materials (FLASHit) , Istituto di Struttura della Materia-CNR (ISM-CNR) , 00015 Monterotondo Scalo , Italy.
J Phys Chem Lett. 2018 Sep 6;9(17):5002-5008. doi: 10.1021/acs.jpclett.8b02117. Epub 2018 Aug 21.
In this work, we show how to control the morphology of femtosecond laser melted gold nanosphere aggregates. A careful choice of both laser fluence and wavelength makes it possible to selectively excite different aggregate substructures to produce larger spherical nanoparticles, nanorods, and nanoprisms or necklace-like 1D nanostructures in which the nanoparticles are interlinked by bridges. Finite integral technique calculations have been performed on the near-field concentration of light in the nanostructures which confirm the wavelength dependence of the light concentration and suggest that the resulting localized high intensities lead to nonthermal melting. We show that by tuning the wavelength of the melting light it is possible to choose the spatial extension of the ensembles of NPs heated thus allowing us to exhibit control over the morphology of the nanostructures formed by the melting process. By a proper combination of this method with self-assembly of chemically synthesized nanoparticles, one can envisage the development of an innovative high-throughput high-resolution nanofabrication technique.
在这项工作中，我们展示了如何控制飞秒激光熔化的金纳米球聚集体的形态。仔细选择激光能量密度和波长，可以选择性地激发不同的聚集体子结构，从而产生更大的球形纳米颗粒、纳米棒、纳米棱镜或项链状的一维纳米结构，其中纳米颗粒通过桥相互连接。已经对纳米结构中光的近场浓度进行了有限积分技术计算，证实了光浓度对波长的依赖性，并表明由此产生的局部高强度导致非热熔化。我们表明，通过调整熔化光的波长，可以选择被加热的纳米颗粒集合体的空间扩展，从而使我们能够控制由熔化过程形成的纳米结构的形态。通过将这种方法与化学合成纳米颗粒的自组装适当结合，可以设想开发一种创新的高通量高分辨率纳米制造技术。
