Interfacial growth behavior of SnO2 nanorods on {11(2)over-bar0} and {10(1)over-bar0} facets of alpha-Fe2O3

SnO2 nanorods with specific growth directions, [101] or [001], were fabricated on alpha-Fe2O3 substrates via a simple hydrothermal method. The growth behavior of SnO2 nanorods is facet-selective. Both {11 (2) over bar0} and {10 (1) over bar0} facets of alpha-Fe2O3 are favorable to direct the growth of SnO2 nanorods. The correlation between the crystallographic orientation of SnO2 and the facets of alpha-Fe2O3 is characterized by TEM observations and investigated on the basis of the interfacial lattice compatibility. Furthermore, the distribution and coordination of oxygen atoms at the interface of alpha-Fe2O3-SnO2 heterostructure are analyzed, which reveals that only slight deviations from their original equilibrium positions are allowed for the formation of heterogeneous interface. And this lower energy activated interfacial construction is beneficial to the feasibility and stability of heterostructures.