Ahmed Waqqar, Glass Christian, van Ruitenbeek Jan M
Kamerlingh Onnes Laboratory, Niels Bohrweg 2, Leiden University, 2333 CA Leiden, The Netherlands.
Nanoscale. 2014 Nov 7;6(21):13222-7. doi: 10.1039/c4nr04122d.
We report a seedless protocol based on the oriented attachment of nanoparticles for the synthesis of Au nanoworms (NWs). NWs are grown by reducing HAuCl4 with ascorbic acid (AA) in high pH reaction medium and in the presence of growth directional agents, cetyltrimethylammonium bromide (CTAB) and AgNO3. Although we have used the same reducing and growth directional agents as typically used for the synthesis of Au nanorods, the growth mechanism of NWs is markedly different from that of nanorods. Instead of the anisotropic growth of seed particles, the NWs grow through oriented attachment of nanoparticles. By varying different reaction parameters we have seen that the length of NWs can be controlled from tens of nanometers to a micrometer. Furthermore, the aspect ratio (AR) can be tuned from 2 to 30. This is almost the whole range of AR and length for Au nanorods so far achieved with seed-mediated multiple step synthesis protocols.
我们报道了一种基于纳米粒子定向附着的无籽合成金纳米蠕虫（NWs）的方法。通过在高pH反应介质中，在生长定向剂十六烷基三甲基溴化铵（CTAB）和硝酸银（AgNO3）存在的情况下，用抗坏血酸（AA）还原氯金酸（HAuCl4）来生长NWs。尽管我们使用了与通常用于合成金纳米棒相同的还原剂和生长定向剂，但NWs的生长机制与纳米棒明显不同。NWs不是通过种子颗粒的各向异性生长，而是通过纳米粒子的定向附着生长。通过改变不同的反应参数，我们发现NWs的长度可以从几十纳米控制到一微米。此外，纵横比（AR）可以从2调整到30。这几乎是迄今为止通过种子介导的多步合成方法所实现的金纳米棒的AR和长度的整个范围。
