Laocharoensuk Rawiwan, Sattayasamitsathit Sirilak, Burdick Jared, Kanatharana Proespichaya, Thavarungkul Panote, Wang Joseph
Biodesign Insititute, Department of Chemical Engineering, Arizona State University, Tempe, Arizona 85287, USA.
ACS Nano. 2007 Dec;1(5):403-8. doi: 10.1021/nn700255x.
Step-like porous gold nanowires of different shapes and diameters have been prepared by sequentially depositing alloy segments composed of different gold/silver ratios and de-alloying the silver component. For example, step-cone and nano-barbell porous gold nanowires were generated by a membrane-templated sequential deposition of gold-silver alloy segments from plating solutions of respectively decreasing or alternating gold/silver composition ratios. Alloy segments of different gold/silver ratios, prepared by using different plating potentials, also lead to multistep nanowires. In addition to step-like nanowires, we describe the preparation of cone- and bone-shaped porous nanowires from alloy nanowires of longitudinally changing compositions, generated via deposition from a flowing plating solution of a continuously changing composition. Such customization of the porous gold nanostructure is attributed to the chemical removal of silver and the different extents of gold reordering from alloy segments of different compositions. The latter leads to porous gold segments of smaller diameters from silver-rich alloy segments. The new "nanomachining" concept is versatile and could be extended to nanowires of diverse shapes with a variety of properties, generating an attractive assortment of nano-hardware.
通过依次沉积由不同金/银比例组成的合金段并去除银组分，制备了不同形状和直径的阶梯状多孔金纳米线。例如，通过膜模板法从金/银组成比例分别递减或交替的电镀溶液中依次沉积金银合金段，生成了阶梯锥形和纳米杠铃形多孔金纳米线。通过使用不同的电镀电位制备的不同金/银比例的合金段，也能得到多步纳米线。除了阶梯状纳米线，我们还描述了由纵向成分变化的合金纳米线制备锥形和骨形多孔纳米线的方法，这些合金纳米线是通过从成分不断变化的流动电镀溶液中沉积而生成的。多孔金纳米结构的这种定制归因于银的化学去除以及不同成分合金段中金重新排列的不同程度。后者导致了富含银的合金段形成直径较小的多孔金段。这种新的“纳米加工”概念具有通用性，可扩展到具有各种特性的不同形状的纳米线，从而产生一系列引人注目的纳米硬件。
