The emergence of metal nanoparticles and other nanostructured materials in applications ranging from medical procedures to solar cells has raised concerns regarding their stability in different extreme environments. This presentation will highlight recent work undertaken at Sandia National Laboratories’ Ion beam Laboratory to understand the stability of gold nanoparticles to various ion beam irradiation and implantation conditions. To achieve an understanding of the dynamics that occur during the bombardment of gold nanoparticles, this study utilized an in situ ion irradiation transmission electron microscope (I3TEM). This facility permits real time observation with sub-nanometer resolution of the nanoparticles during ion irradiation with a 6 MV Tandem accelerator, ion implantation with a 10 kV Colutron, or both concurrently. In the ion irradiation portion of this study, the particles were bombarded with either copper or gold ions at 3 MeV. The evolution of the supported nanoparticles during ion irradiation showed both thermal and sputtering effects, as evidenced by the formation of large agglomerates, as well as new satellite particles surrounding the original particles. To fully understand the extent of both of these effects, a series of electron tomography and in situ ion irradiation steps were used to produce a time separated series of 3D models during ion irradiation. In addition to heavy ion irradiation, the evolution of the particles was investigated during ion implantation of noble gasses The insight gained from these experiments will be used to further elucidate the governing mechanisms associated with the structural evolution of the gold nanoparticles, as a function of nanoparticle size and structure in addition to irradiation condition.
This work was partially supported by the Division of Materials Science and Engineering, Office of Basic Energy Sciences, U.S. Department of Energy. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-AC04-94AL85000.