Method for the Growth and Stabilization of Rare Earth Nano-Particles*

We are developing a process to create rare-earth metal (REM), nanoparticles (NPs), to the end of studying their magnetic and electrical properties. The large redox potential of REMs hinders the formation and stabilization of these NPs, requiring: a strong reducing agent to form the NPs, and their protection from ambient conditions.
Firstly, the ease and efficacy of several organo-metallic reduction compounds, with sodium as an electron source, were compared: 15-crown-5, Benzophenone (anion and dianion), and naphthalene; with naphthalene showing to be the most consistent and convenient due to its: relatively high reduction potential, stability, and singly reduced state.
Secondly, we then compared methods of passivating the NPs; this consisted of looking at the relative stability of NPs using combinations of: ligation with 1-octylamine. Preliminary observations indicate ligation alone provides little protection from oxidation for the pure REM NPs, and is only able to prevent agglomeration.