New horizons for the synthesis of nanoparticles: Germanium nanoparticles from metastable GeBr-solutions

Abstract We present the synthesis and characterization of halide-terminated colloidal Ge nanoparticles of 2–10 nm with a narrow size distribution, synthesized via a novel reaction route. The nanoparticles are prepared by the disproportionation reaction of metastable Ge(I)X solutions and are obtained in a maximum yield of 79%. Control of the nanoparticle size is achieved by varying the aging time and/or temperature. The halide termination of the nanoparticles is a perfect prerequisite for further surface functionalization but also leads to a high sensitivity of the germanium nanoparticles to water and air.