Pure multistep oriented attachment growth kinetics of surfactant-free SnO2nanocrystals

Abstract

In this work, crystal growth kinetics of surfactant-free nanocrystalline SnO₂ in distilled water at 175–250 °C were investigated. The growth rate followed the type of asymptotic curve in hundreds of hours, which could be fitted by the multistep oriented attachment (OA) kinetic model. High-resolution transmission electron microscope (HRTEM) data also indicated crystal growth occurring via the multistep OA mechanism. During the growth of SnO₂, the concentration of Sn ions in the aqueous solution was examined. It reveals that the unsaturated situation of SnO₂ results in crystal growth via the pure OA mechanism. A growth model of self-integration of conjugated nanocrystals was discussed for understanding the OA behavior.