Iron oxide, doping

Bifunctional biolabels with magnetic and luminescent properties are highly desirable for in vitro and in vivo bioimaging. There are several strategies to use NPs to comprise such biolabels, such as core/shell NPs, for example, the magnetic cores of iron oxide doped with cobalt and neodymium and luminescent shells of Gd203 Eu (Dosev et al., 2005,2007). 

P. Tartaj and J. Tartaj, Microstructural evolution of iron-oxide-doped alumina nanoparticles syn-... 

The present case deals with the synthesis and characterisation of mesoporous iron oxide doped silica films [174]. 

As already outlined, mixed metal oxide films and powders play important roles as sensors, catalysts and as supports for catalytically active species. In particular, iron oxide doped silica find application in catalytic processes like Friedel-Crafts alkylation, the conversion of CH4 to HCHO and in the decomposition of methanol and phenol [175]. 

More recently, Bard s group reported the use of SPECM for rapid screening of photocatalysts [136,137] (Chapter 16). Here, photocatalysts with different compositions were deposited as 300pm spots on a conducting glass substrate. Typically, these spots consisted of iron oxide doped with... 

Song X, Gong H, Yin S et al (2014) Ultra-small iron oxide doped polypyrrole nanoparticles for in vivo multimodal imaging guided Photothermal therapy. Adv Fund Mater 24 1194—1201... 

Figure 2.8. Schematic representation of iron oxide doped with lithium...

Fig. 1(b) represents the selectivity to styrene as a ftmcfion of time fijr the above catal ts. It is observed that the selectivity to styrene is more than 95% over carbon nauofiber supported iron oxide catalyst compared with about 90% for the oxidized carbon nanofiber. It can be observed that there is an increase in selectivity to styrene and a decrease in selectivity to benzene with time on stream until 40 min. In particrdar, when the carbon nanofiber which has been treated in 4M HCl solution for three days is directly us as support to deposit the iron-precursor, the resulting catalyst shows a significantly lows selectivity to styrene, about 70%, in contrast to more than 95% on the similar catalyst using oxidized carbon nanofiber. The doping of the alkali or alkali metal on Fe/CNF did not improve the steady-state selectivity to styrene, but shortened the time to reach the steady-state selectivity. 

Leygraf, C., Hendewerk, M., and Somorjai, G.A., Magnesium- and silicon-doped iron oxides for the photocatalyzed production of hydrogen from water by visible light (2.2 eV < hv < 2.7 eV),. Catal., 78,341,1982. 

Sieber KD, Sanchez, C, Turner JE, Somorjai GA (1985) Preparation, electrical and photoelectrochemical properties of magnesium doped iron oxide sintered discs. Mat Res Bull 20 153-162... 

Production. The iron oxide pigments described in Section 5.1.1 are either doped or coated with cobalt ... 

The hematite platelets show a predominantly metallic effect. Very thin particles with a thickness of 50 to 400 nm display a pale copper gloss, which is indicative of interference. The shade can be varied and the properties of the platelets can be controlled by doping. A1 or Mn are incorporated by substitution of Fe in the hematite lattice, and Si is incorporated interstitially [5.240]. Laminar iron oxide pigments are interesting because of their excellent fastness to light, outdoor exposure and their good mechanical stability. Main applications up to now are automotive lacquers and cosmetics. 

Iodine-doped hematite has also been studied. The iodine-doped thin films of iron oxide were obtained by spray pyrolysis. The condition for the preparation was not described in detail, apart that a mixture of an 80% ethanolic solution of 0.01 M iodine and 0.1 M FeCl3 was used. Undoped films of 50 nm film thickness showed a maximum photocurrent density of 1.1 mA/cm2, while a 100 nm thick iodine-doped films had a maximum photocurrent density of 5 mA/cm2 at 0.82 V vs. NHE at pH 13 [37]. These measurements were performed with a xenon lamp with a light irradiation of only 150 mW/cm2. At the same condition, it was suggested by model calculation that an optimized stack of five iodine-doped hematite electrodes was expected to yield a photocurrent density of 15 mA/cm2. 

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