LPCNO, Université de Toulouse , CNRS, INSA, UPS, 135 avenue de Rangueil, F-31077 Toulouse Cedex 4, France.
Departamento de Química, Facultad de Ciencias, Universidad Nacional de Colombia , Sede Bogotá, Carrera 30 No. 45-03, 111321 Bogotá, Colombia.
Langmuir. 2017 Jun 6;33(22):5456-5463. doi: 10.1021/acs.langmuir.7b00477. Epub 2017 May 22.
Gold nanowires with a mean diameter of 1.7 nm were synthesized by reduction of HAuCl in a solution of oleylamine (OY) in hexane. A bilayer of oleylammonium chloride/oleylamine at the surface of the raw nanowires was evidenced by NMR and diffusion ordered spectroscopy (DOSY) experiments. After washing a monolayer of oleylammonium chloride remained at the surface of the nanowires. The oleylammonium chloride layer could be progressively replaced by a phosphine shell as evidenced with NMR and DOSY experiments, which are in good agreement with the adsorption energies given by density functional theory calculations. The nanowires crystallize into hexagonal superlattices with a lattice parameter that can be tailored depending on the ligand shell. Small-angle X-ray scattering showed the following lattice parameters: Au@OYCl(OY) (a = 7.2 nm) > Au@TOPO/OY (a = 6.6 nm) > Au@ OYCl (a = 4.1 nm) > Au@TOP (a = 3.75 nm). This is one of a few examples of surface modification of ultrathin nanowires that does not alter their morphology. Moreover, the nanowires coated with phosphines exhibited long time stability (at the opposite of other ligands like thiols) opening the way to more complex functionalization.
通过在正十六胺（OY）的己烷溶液中还原 HAuCl，合成了平均直径为 1.7nm 的金纳米线。通过 NMR 和扩散有序光谱（DOSY）实验证明了原始纳米线表面存在双层油胺氯化油酸铵/油胺。洗涤后，纳米线表面仍残留单层油胺氯化油酸铵。油胺氯化油酸铵层可以逐步被膦壳取代，这与 NMR 和 DOSY 实验一致，与密度泛函理论计算给出的吸附能一致。纳米线结晶成具有晶格参数的六方超晶格，该晶格参数可以根据配体壳进行调整。小角 X 射线散射显示出以下晶格参数：Au@OYCl（OY）（a = 7.2nm）> Au@TOPO/OY（a = 6.6nm）> Au@OYCl（a = 4.1nm）> Au@TOP（a = 3.75nm）。这是少数几个不改变超细微纳米线形态的表面修饰实例之一。此外，涂覆膦的纳米线表现出长时间的稳定性（与其他配体如硫醇相反），为更复杂的功能化开辟了道路。
