Nanostructured iron

Fig. 10. Scanning electron micrograph of amorphous nanostructured iron powder produced from the ultrasonic irradiation of Fe(CO)5...

Table 8.3 Saturation magnetization, relative remanence and coercivity for different crystallite sizes of nanostructured iron.

Rusina O, Linnik O, Eremenko A, Kisch H. Nitrogen photofixation on nanostructured iron titanate films. Chem Eur J 2003 9 561-5. 

Nandi etal. prepared the titanium (IV)-doped synthetic nanostructured iron (III) oxide (NITO) and PPy nanocomposites (NITO/PPy) via in situ... 

Template-free approaches can also be employed, as recently reported by Wei et al. who use a simple hydrothermal approach to synthesise hollow a-FcaOs nanostructures. Iron (iii) chloride and urea is treated hydrothermally in a glycerol/water mixture for 30 minutes at 140 °C to... 

Li, C. Gu, L Xsukamoto S. vanAken, PA. Maier J., Low-Xemperature lonic-Liquid-Based Synthesis of Nanostructured Iron-Based Fluoride Cathodes for Lithium Batteries, Adv, Mater, 2010, 22, 3650-3654. 

Mamuru SA, Ozoemena KI (2010) Heterogeneous electron transfer and oxygen reduction reaction at nanostructured Iron(n) phthalocyanine and its MWCNTs nanocomposites. Electroanalysis 22(9) 985-994... 

Figure 25.6. A strip of reactive foil that has had one end dip-coated with sol-gel nanostructured iron (111) oxide/ aluminum (see image on the left) and an image of the reaction of the foil which provides the thermal stimulus needed to ignite the sol-gel energetic.

Figure 25.8. TGA trace of mass loss and temperature as a function of time for the reduction of sol el iron (III) oxide aerogel to nanostructured iron metal by pure hydrogen at a flow rate of 50 standard cubic centimeters per minute (seem).

Ultrasonic irradiation of iron pentacarbonyl in decane solution in the presence of silica gel produces a silica-supported amorphous nanostructured iron.io The iron particles range in size from 3 to 8 pm. This catalyst is a very active material for Fischer-Tropsch hydrogenation of CO. Figure 2 compares the activity (in terms of turnover frequency of CO molecules converted per catalytic site per second) of silica-supported nanophase iron and conventional silica-supported iron (prepared by the incipient wetness method) as a function of temperature. 

The runs reported in the figure above have been performed with a silica-supported nanostructured iron catalyst prepared under sonication (Fe loading wt% = 10.94, dispersion Dm% = 1.85) compared to the conventional silica-supported crystalline iron catalyst prepared by the incipient wetness method (Fe wt% = 9.91, Dm% = 1-86). The catalysts were tested with H2/CO = 3.48 and 1 bar. 

Sonochemically Prepared Nanostructured Iron. The consolidated iron pellet had a homogenous microstructure as confirmed by SEM taken at lOOX magnification (Figure 10) and it had a density of 100%. The carbon and oxygen contents were determined to be 0.05% and 1.1% respectively. In the XRD spectra the major peaks were assigned to the a-Fe phase and line broadening analysis revealed the average crystallite size in the consolidated specimen to be 40 nm. 

Hardness. The nanostructured M50 compact had a hardness of 69 Rockwell C (RC) as compared to a hardness of 58-62 RC for conventional, commercial M50 steel. The hardness of the consolidated iron sample was 37 RC as compared to that of conventional micron sized iron compacts (4-5 RC). Since the nanostructured iron has a hardness approximately seven times that of the conventional, iron, it is therefore reasonable to ar e that the marginally higher hardness in the case of the M50 compact results from the iron matrix rather than from the precipitate. 

H. Guerault, M. Famine, J.M. Greneche, Mossbauer study of nanostructured iron fluoride powders. J. Phys. Condens. Matter 12, 9497-9508 (2000)... 

H. Guerault, I. Labaye, J.-M. Greneche, Recoilless factors in nanostructured iron-based powders. Hyp. Inter. 136, 57-63 (2001)... 

Bai, A. and C.-C. Hu, Cyclic voltammetric deposition of nanostructured iron-group alloys in high-aspect ratios without using templates. Electrochem. Commun., 2003. 5 p. 619-624. 

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