Moutet Pierre, Lacroix Lise-Marie, Robert Antoine, Impéror-Clerc Marianne, Viau Guillaume, Ressier Laurence
†Université de Toulouse, LPCNO (Laboratoire de Physique et Chimie des Nano-Objets), UMR 5215 INSA-CNRS-UPS, 135 Avenue de Rangueil, F-31077 Toulouse, France.
‡Laboratoire de Physique de Solides, UMR 8502, Bat. 510, Université Paris-Sud, F-91405 Orsay, France.
Langmuir. 2015 Apr 14;31(14):4106-12. doi: 10.1021/acs.langmuir.5b00299. Epub 2015 Apr 1.
Ultrathin gold nanowires (NWs) dispersed in hexane were prepared by chemical reduction of HAuCl4 in oleylamine, along with nanospheres (NSs), side products of the reaction. X-ray photoelectron spectroscopy and small-angle X-ray scattering evidenced a stabilization of these nano-objects by oleylammonium chloride surfactants. The directed assembly of these nano-objects on surfaces was performed by atomic force microscopy (AFM) nanoxerography in a few seconds. Selective assembly of gold NWs only occurred on positively charged patterns, while NSs assembled more specifically on the negatively charged ones. This sorting suggests that the strong electric field generated by the charge patterns induced a negative effective charge on the gold NWs and a weak positive effective charge on the NSs. Such difference could be explained by the ion organization at the colloid surface, monolayered in the case of NWs, and bilayered in the case of NSs. By adjusting the design of the positive patterns and the experimental conditions of development, single gold nanowires were successfully assembled by AFM nanoxerography on predefined sites of surfaces without damaging them, opening the way for future electrical and mechanical characterizations.
通过在油胺中化学还原氯金酸制备了分散在己烷中的超薄金纳米线（NWs），同时还生成了纳米球（NSs），即该反应的副产物。X射线光电子能谱和小角X射线散射证明了这些纳米物体通过油胺氯化物表面活性剂得以稳定。通过原子力显微镜（AFM）纳米静电复印在几秒钟内完成了这些纳米物体在表面的定向组装。仅金纳米线选择性地组装在带正电的图案上，而纳米球则更特异性地组装在带负电的图案上。这种分选表明，电荷图案产生的强电场在金纳米线上诱导出负有效电荷，而在纳米球上诱导出弱正有效电荷。这种差异可以通过胶体表面的离子组织来解释，纳米线的情况是单层的，纳米球的情况是双层的。通过调整正图案的设计和显影的实验条件，通过AFM纳米静电复印成功地在表面的预定位置组装了单根金纳米线，且未对其造成损坏，为未来的电学和力学表征开辟了道路。
