Controlled self-decoration of Mo_6S _y i_ z (8.2 ≤ y + z ≤ 10) nanowires and their transformation to MoS_2 nanotubes with gold nanoparticles

摘要

Nanowires and nanotubes decorated with gold nanoparticles are known for their excellent sensing and catalytic properties. However, the decoration of transition-metal dichalcogenide nanotubes can be very complex. Here we report on a simple procedure that enables efficient production and purification of thin bundles of Mo_6S _y I _z (8.2 ≤ y + z ≤ 10) nanowires decorated with gold nanoparticles and their transformation to gold-decorated MoS_2 nanotubes. We isolated several hundred milligrams of nanowire bundles that were several microns long with average diameters of around 40 nm, and formed a stable dispersion in water without added surfactants. Gold nanoparticles were directly deposited on the nanowire bundles either in a solution or on a substrate at room temperature in a single-step reaction without any additional reducing reagents. The number of gold nanoparticles on a nanowire bundle is controlled by changing the concentration of chloroauric acid HAuCl_4·3H_2O in the solution. Since the nanowires can serve as precursor crystals for fabrication of nanotubes, we were able to transform gold-decorated nanowires and produce gold-decorated MoS_2 nanotubes.