Solution Synthesis and Characterization of Quantum Confined Ge Nanoparticles

A solution synthesis of crystalline Ge nanoparticles (nc - Ge ) is reported. The metathesis reaction of NaGe with excess GeCl 4 in glyme solvents produces nc - Ge. Metathesis reactions between KGe and excess GeCl 4 or GeCl 2:(dioxane) in glyme and Mg 2 Ge and excess GeCl 4 in diglyme and triglyme were also investigated. The surface of these nanoparticles is terminated with alkyl groups by reaction with alkyl Li and Grignard reagents. The alkyl-terminated crystalline Ge nanoparticles (R̂-nc-Ge) were characterized by Fourier transform infrared spectroscopy, high-resolution transmission electron microscopy, powder X-ray diffraction, UV−vis absorption spectroscopy, photoluminescence, and photoluminescence excitation spectroscopy. The optical properties of R̂-nc-Ge made by this method agree with predictions from quantum confinement models.