Synthesis of cube-shaped gold nanostructures by electron irradiation

摘要

The needle-like gold nanostructures were synthesized by using chloroauric acid (HAuCl4) as a metal precursor and sodium borohydride (NaBH4) as the reducing agent. These needle-like nanostructures of gold were irradiated with high energy electrons (E~6MeV, (|)-1012ecm~2s~1). The pre- and post-irradiated gold nanostructures were characterized by Scanning Electron Microscopy (SEM), UV-vis spectroscopy, X-ray Diffraction (XRD) and contact angle measurement (GBX-Model Digidrop) techniques. The results of the SEM revealed that after electron irradiation, the needle-like gold structures got fragmented into identical cube-shaped gold nanostructures, though of different sizes. The XRD analysis indicated that the average crystallite size of the gold nanostructures remained unchanged even after irradiation with high energy electrons. A glass surface showed hydrophilic behavior when coated with needle-like nanostructures and became ultra hydrophilic when coated with cube-shaped gold nanostructures.