In Situ TEM Observation of MgO Nanorod Growth

The controlled growth of MgO nanorods was investigated under electron irradiation in transmission electron microscopes at accelerating voltages from 120 to 300 kV in the temperature range from −175 to 610 °C. The nanorod growth on the surface of MgO crystals was induced by Au, Pt, Ni, or Co particles of 2−4 nm in size. The nanorods were grown up to 8 nm after 5−30 min of electron irradiation time with beam current densities of 100−600 A/cm<sup>2</sup>. The mechanism of nanorod formation and growth is explained on the basis of electrostatic interactions between positive ions of MgO species and negatively charged metal particles.