Flutelike Porous Hematite Nanorods and Branched Nanostructures: Synthesis, Characterisation and Application for Gas-Sensing
RIS ID
24874
Abstract
Flute-like porous a-Fe2O3nanorods and branched nanostructuressuch as pentapods and hexapods wereprepared through dehydration and recrystallisationofhydrot hermally synthesisedb-FeOOH precursor. Transmissionelectron microscopy (TEM),high-resolution TEM and selected areaelectron diffraction analyses reveal thatthe nanorods, which grow along the[110] direction, have nearly hollow cavitiesand porous walls with a pore sizeof2050 nm. The hexapods have sixsymmetric arms with a diameter of6080 nm and length of40090 0 nm. Thegrowth direction ofthe arms in thehexapod-like nanostructure is alsoalong the [110] direction, and there is adihedral angle of69.5 o between adjacentarms. These unique iron oxidenanostructures offer the first opportunityto investigate their magnetic andgas sensing properties. The nanostructuresexhibited unusual magnetic behaviour,with two different Morin temperaturesunder field-cooled and zerofield-cooled conditions, owing to theirshape anisotropy and magnetocrystallineanisotropy. Furthermore, the a-Fe2O3 nanostructures show muchbetter sensing performance towardsethanol than that ofthe previously reportedpolycrystalline nanotubes. Inaddition, the a-Fe2O3 nanostructurebased sensor can selectively detectformaldehyde and acetic acid amongother toxic, corrosive and irritant vapoursat a low working temperaturewith rapid response, high sensitivityand good stability.
Publication Details
Gou, X. L., Wang, G., Kong, X. y., Wexler, D., Horvat, J., Yang, J. Park, J. (2008). Flutelike Porous Hematite Nanorods and Branched Nanostructures: Synthesis, Characterisation and Application for Gas-Sensing. Chemistry: A European Journal, 14 (19), 5996-6002.