Synthesis of gram-scale germanium nanocrystals by a low-temperature inverse micelle solvothermal route

Abstract

We report a simple low-temperature inverse micelle solvothermal route for the synthesis of a large quantity of single-crystalline germanium nanocrystals. X-ray diffraction measurement indicates that the as-prepared nanocrystals are composed of pure Ge with a cubic structure. The morphology, size, chemical composition, crystallinity, and structural features of the as-prepared nanocrystals were characterized by transmission electron microscopy and energy-dispersive x-ray spectroscopy.

Group IV Nanoparticles: Synthesis, Properties, and Biological Applications

“…Highly crystalline Ge nanocrystals in the size range of 2–5 nm synthesized by reduction of ionic salts such as GeCl 4 in the inverse micelles exhibit photoluminescence in the range 350–700 nm 232. Ge nanocrystals with an average diameter of 24 nm are synthesized by the reduction of chlorogermaniums with sodium in the inverse micelle solvents using the surfactant C 12 E 5 as a capping agent 233. Reduction of GeCl 4 using strong hydride reducing agents in the reverse micelles produces 5 nm Ge nanocrystals with a narrow size distribution 234.…”

Size and emission color tuning in the solution phase synthesis of highly luminescent germanium nanocrystals

“…[14][15][16][17][18][19][20][21] Other methods include thermal co-reduction of Ge(II) and amido based precursors, 6,22,23 aqueous phase reduction of GeO 2 powders by NaBH 4 , 24 and other high temperature chemical reduction methods. [25][26][27][28][29][30][31] However, disadvantages associated with these methods include synthetically involved precursor synthesis, long reaction times, high temperatures and pressures, and extensive post synthetic purification procedures. 1,29 As well as the variation in size distribution, morphology and surface chemistries reported above, significant inconsistencies also exist in the photophysical properties of these nanostructures, precluding a detailed understanding of their size-dependent characteristics.…”

Synthesis of Nanoparticles via Solvothermal and Hydrothermal Methods

“…The width of the nanorods is mostly between 30 and 70 nm [146]. ZnSe nanorods can be synthesized by heating Zn and Te powders in a 1.1:1 ratio in a 70 % filled Teflon-lined autoclave at 170 C for 16 h. The nanorods are very uniform with a typical width of~50 nm [147].…”

“…When the surfactant is changed to pentaethylene glycol ether (C12E5), a mixture of spherical, triangular, and hexagonal Ge NPs is produced with diameters ranging from 15 to 70 nm (Fig. 7) [170]. The shape of Ge NPs can be tuned by controlling surfactant amount.…”