Structure versus properties in α-Fe2O3 nanowires and nanoblades.
نویسندگان
چکیده
We report structure/property relationships in bicrystalline α-Fe2O3 nanowires (NWs) and nanoblades (NBs), synthesized by thermal oxidation of iron foils with different surface roughness. The electrical properties of individual nanostructures were studied by in situ transmission electron microscopy. Current-voltage (I-V) measurements using gold electrodes showed that a Schottky contact forms between α-Fe2O3 NWs whereas an ohmic contact forms between α-Fe2O3 NBs. The difference in transport properties is attributed to the existence of oxygen vacancies in the coincidence-site-lattice boundary region of α-Fe2O3 NBs. Magnetic measurements indicate that the temperature-dependent zero-field-cooled magnetization rises more rapidly near the Morin transition temperature for α-Fe2O3 NBs than that for NWs. The distinct magnetic properties of the NBs are ascribed to the enhanced magnetic order induced by the structural order in the two-dimensional NBs. These α-Fe2O3 NBs are promising building blocks for electronic and magnetic devices since their 2D geometries facilitate integration into devices with realistic pathways to manufacturing. In addition, our study shows that boundary engineering is an effective approach for tailoring the physical properties of nanomaterials.
منابع مشابه
Morphological transformation of hematite nanostructures during oxidation of iron.
Oxidation of metals usually results in the formation of an oxide nanostructure with poorly controlled growth morphologies. By employing a simple mechanical approach that uses sandblasting to modify the surface roughness of iron substrates, we demonstrate that the morphologies of hematite (α-Fe2O3) nanostructures varying from the growth of one-dimensional nanowires to two-dimensional nanoblades ...
متن کاملDefect-induced enhanced photocatalytic activities of reduced α-Fe2O3 nanoblades.
Bicrystalline α-Fe2O3 nanoblades (NBs) synthesized by thermal oxidation of iron foils were reduced in vacuum, to study the effect of reduction treatment on microstructural changes and photocatalytic properties. After the vacuum reduction, most bicrystalline α-Fe2O3 NBs transform into single-layered NBs, which contain more defects such as oxygen vacancies, perfect dislocations and dense pores. B...
متن کاملEnhanced Phtocatalytic Activity of α-Fe2O3 Nanoparticles Using 2D MoS2 Nanosheets
α‒Fe2O3/MoS2 nanocomposites were synthesized via hydrothermal method and characterized in terms of crystal structure, particle size and morphology, elemental purity and optical properties. Results confirmed the formation of α‒Fe2O3/MoS2 nanocomposites containing hematite nanoparticles with average diameter of 40 nm and MoS2 nanosheets with hexagonal crystal structure and sheet thickness o...
متن کاملMagnetic properties of fluffy Fe@α-Fe2O3 core-shell nanowires
: Novel fluffy Fe@α-Fe2O3 core-shell nanowires have been synthesized using the chemical reaction of ferrous sulfate and sodium borohydride, as well as the post-annealing process in air. The coercivity of the as-synthesized nanowires is above 684 Oe in the temperature range of 5 to 300 K, which is significantly higher than that of the bulk Fe (approximately 0.9 Oe). Through the annealing process...
متن کاملSelective Synthesis of Fe2O3 and Fe3O4 Nanowires Via a Single Precursor: A General Method for Metal Oxide Nanowires
Hematite (α-Fe2O3) and magnetite (Fe3O4) nanowires with the diameter of about 100 nm and the length of tens of micrometers have been selectively synthesized by a microemulsion-based method in combination of the calcinations under different atmosphere. The effects of the precursors, annealing temperature, and atmosphere on the morphology and the structure of the products have been investigated. ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Nanotechnology
دوره 27 3 شماره
صفحات -
تاریخ انتشار 2016