Hydrothermal Synthesis, Structural Characteristics, and Enhanced Photocatalysis of SnO₂/α-Fe₂O₃ Semiconductor Nanoheterostructures

Abstract

Branched SnO(2)/alpha-Fe(2)O(3) semiconductor nanoheterostructures (SNHs) of high purity were synthesized by a low-cost and environmentally friendly hydrothermal strategy, through crystallographic-oriented epitaxial growth of the SnO(2) nanorods onto the alpha-Fe(2)O(3) nanospindles and nanocubes, respectively. It was demonstrated that the SnO(2) nanorods would change their preferential growth direction on the varied alpha-Fe(2)O(3) precursors with distinct crystallographic surface, driven by decrease in the distortion energy induced by lattice mismatch at the interfaces. All of the prepared SNHs were of high purity, ascribing to the successful preinhibition of the SnO(2) homonucleation in the reaction system. Significantly, some of the SnO(2)/alpha-Fe(2)O(3) SNHs exhibited excellent visible light or UV photocatalytic abilities, remarkably superior to their alpha-Fe(2)O(3) precursors, mainly owing to the effective electron-hole separation at the SnO(2)/alpha-Fe(2)O(3) interfaces.