An efficient microwave-assisted synthesis method for the production of water soluble amine-terminated Si nanoparticles

摘要

Silicon nanoparticles can be considered a green material, especially when prepared via a microwave-assisted method without the use of highly reactive reducing agents or hydrofluoric acid. A simple solution synthesis of hydrogen-terminated Si-and Mn-doped Si nanoparticles via microwave-assisted synthesis is demonstrated. The reaction of the Zintl salt, Na _4Si _4, or Mn-doped Na _4Si _4, Na _4Si _(4(Mn)), with ammonium bromide, NH _4Br, produces small dispersible nanoparticles along with larger particles that precipitate. Allylamine and 1-amino-10-undecene were reacted with the hydrogen-terminated Si nanoparticles to provide water solubility and stability. A one-pot, single-reaction process and a one-pot, two-step reaction process were investigated. Details of the microwave-assisted process are provided, with the optimal synthesis being the one-pot, two-step reaction procedure and a total time of about 15min. The nanoparticles were characterized by transmission electron microscopy (TEM), x-ray diffraction, and fluorescence spectroscopies. The microwave-assisted method reliably produces a narrow size distribution of Si nanoparticles in solution.