High-Temperature Plateau-Rayleigh Growth of Beaded SiC/SiO2 Nanochain Heterostructures

Abstract

The Plateau-Rayleigh (P-R) crystal growth was recently proposed and dramatically extended the one-dimensional nanomaterials synthesis due to its tunable morphological features. Previously reported P-R growth is mainly focused on the relative low-temperature reactions (<1273 K, which is less than the melting point of reaction products or intermediate products), while high-temperature P-R growth with a molten state is rarely studied. To extend P-R growth to high temperature and reveal the underlying mechanism, herein we take the synthesis of SiC/SiO2 heterostructures as the prototype. With optimized growth temperature, we reported a novel high-temperature P-R growth of the beaded SiC/SiO2 nanochain heterostructures through a vapor-phase synthesis. The as-obtained SiC/SiO2 nanochain heterostructures involved the single-crystalline 3C-SiC core with diameters of ∼20 nm, the amorphous SiO2 shell with thicknesses of 200-300 nm, and many uniform periodic amorphous SiO2 beads with diameters of 800-1000 nm. Further experiments and thermodynamics analysis reveal that the saturated vapor pressure and viscosity of the intermediate product SiO play a key role in this growth. This study not only provides a novel extension of P-R growth with the synthesis of SiC/SiO2 heterostructures but also reveals the significance of the saturated vapor pressure and viscosity of the intermediate product in the high-temperature P-R growth. It is expected that such findings will facilitate the applications of one-dimensional nanomaterials synthesis.