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3704832 
Journal Article 
Understanding growth mechanisms of epitaxial manganese oxide (Mn3O4) nanostructures on strontium titanate (STO) oxide substrates 
Liu, JiaYin; Cheng, X; Nagarajan, V; Xin, HuoLin 
2015 
5 
2 
277-284 
WOS:000358147300017 
The role of substrate orientation on interface registry and nanocrystal shape has been investigated for epitaxial manganese oxide (Mn3O4) nanocrystals. Mn3O4 (101) nanoplatelets and (112)-orientated nanowires have been successfully deposited on (111) and (110) SrTiO3 (STO) substrates, respectively. Under higher magnifications, the (101) platelets were found to exhibit step-like growth, spiraling outward from a local dislocation site at the Mn3O4-STO interface. Selected area electron diffraction analysis from transmission electron microscope (TEM) was carried out to determine the in-plane edge directionalities of (101) and (112) Mn3O4. We found the (101) Mn3O4 orientation to exhibit a complex in-plane epitaxial relation of [2 (31) over bar](Mn3O4)//[100](STO) and an out-of-plane relation of [(1) over bar 01](Mn3O4)//[(1) over bar 11](STO). Furthermore, lattice misorientations of 58 degrees in-plane and 35 degrees out-of-plane have been calculated, attributed to the shear caused by the spiral growth. For the (112) Mn3O4 nanowires, the TEM diffraction pattern indicates pyramidal cross-sections based along [0 (11) over bar] STO. Subsequent calculations reveal that the (112) nanowires have their long axis (c-axis) such that [001](Mn3O4)//[110](STO). Thus the nanowires grow preferentially along its longest axis giving rise to the observed shape and anisotropic nature.