Nanoscience - Sapphire's sacrifice
Sapphire nanowires grow using an unexpectedly complicated reaction with oxygen atoms changing between partners in vapor, liquid and solid phases. By concentrating on the triple-junction of the three phases, observations captured with high-resolution electron microscopy at the atomic scale, at high temperature and in real time, reveal a growth process that requires the nanowire to sacrifice some of its mass in order to grow longer. While vapor-liquid-solid growth has been studied previously, these are the first studies at atomic resolution. This investigation by an international team that includes Korea's Pohang University of Science and Technology and DOE's Oak Ridge National Laboratory produced a clearer view of the process, allowing improved understanding of the complicated mass transport involved in the growth of nanowires using a liquid catalyst. The work is published in Science.
November 05, 2010