Synthesis And Characterization Of Cross Structure SnO And High Temperature Stable Monodisperse Superparamagnetic Iron-oxide Nanomaterials

In this paper,Monodisperse superparamagnetic SnO₂-coated iron-oxide nanoparticles(～16.4 nm) have been synthesized via thermal decomposition.The thickness of SnO₂ shells can be controlled from 1～5 nm.As-prepared SnO₂-coated iron-oxide nanoparticles with high saturation magnetization(18 A·m²/kg),are stable up to 600℃,which can be formed stable ferrofluid.It was suggested that the SnO₂ shell acts as a barrier of preventing the growth ofγ-Fe₂O₃ and consequently,avoiding theγ-Fe₂O₃-to-α-Fe₂O₃ phase transition at high temperatures.This paper also reported that cross-like architectures of SnO constructed from single crystalline plates were prepared through thermal decomposition of tetraphenyltin.The crosses are mainly constructed from single crystalline plates with plate surfaces either {001} or {110}. The mechanism for the formation of crosses in both cases is growth twinning,close to 90°,with {112} twin planes.