Wei Qingshan, Ji Jian, Shen Jiacong
College of Material Science and Chemical Engineering, Zhejiang University, Hangzhou, 310027, China.
J Nanosci Nanotechnol. 2008 Nov;8(11):5708-14.
Here we report the two-step synthesis of high aspect-ratio gold nanorods via combining low pH growth and higher cetyltrimethylammonium bromide concentration. The approach is motivated by the "slow growth principle", which has been demonstrated recently as a effective protocol to prepare high aspect-ratio one-dimensional nanostructures. When the pH value of the growth solution gradually decreased, the growth rate of nanorods was significantly decreased and a continuous morphological changing from uniform monodisperse gold nanospheres to extraordinary long gold nanorods occured. By simultaneously decreasing the growth pH and increasing the concentration of cetyltrimethylammonium bromide, the length of gold nanorods could be further elongated to above 2 microm with large aspect-ratio of above 80. This kind of high aspect-ratio gold nanorods could be excellent building blocks for optical or electrical nanodevices in future.
在此，我们报道了通过结合低pH值生长和较高的十六烷基三甲基溴化铵浓度，两步合成高纵横比的金纳米棒。该方法是受“缓慢生长原理”的启发，最近该原理已被证明是制备高纵横比一维纳米结构的有效方案。当生长溶液的pH值逐渐降低时，纳米棒的生长速率显著降低，并且发生了从均匀单分散金纳米球到超长金纳米棒的连续形态变化。通过同时降低生长pH值和增加十六烷基三甲基溴化铵的浓度，金纳米棒的长度可以进一步延长至2微米以上，纵横比大于80。这种高纵横比的金纳米棒未来可能成为光学或电学纳米器件的优良构建块。
