Structure and magnetic properties of synthesized fine cerium dioxide nanoparticles

Effect of Iron Impurities on Magnetic Properties of Nanosized CeO2 and Ce-Based Compounds

“…Therefore, the present study is concentrated on ceria prepared by different technological procedures. It continues our previous investigations [9,10] in order to shed more light on the magnetic behaviours of ceria and Ce-compounds. The nano-sized CeO 2 powders were prepared from the same cerium (III) nitrate hexahydrate using three precipitation procedures with different chemicals.…”

“…A sharp magnetisation reversal at lower magnetic fields seen at the RT hysteresis loops in Figure 4 (left panel) is indicative of the ferromagnetic contribution. This can originate in a large number of structural defects, particularly surface oxygen vacancies mentioned by some authors [17][18][19][20][21], and/or magnetic impurities, namely iron [9,10] contributing to small values of RT ferromagnetic saturation magnetisation of an order of 10 −3 Am 2 /kg, detected also in other usually nonmagnetic compounds [22]. The analysis of the present magnetic measurements of the S4, S5, and S6 samples has resulted in the detection of a small amount of iron impurities, in units of ppm as seen in Table 2.…”

“…A slightly better effect, observed at CeN, corresponds to the higher Fe content followed from the ICP-AES. The spectra of the samples were evaluated using one double-line component with hyperfine parameters (isomer shift, δ, and quadrupole slitting, ∆) not too different in the frame of experimental errors: S4: δ = 0.229 10 [9,10].…”

“…Recently, the magnetic behaviour of nanosized ceria has also been ascribed to a presence of a small amount of magnetic iron-based impurities. Their amount in units of ppm was detected by low-temperature magnetic measurements using a superconducting quantum interference device (SQUID) magnetometer and subsequently confirmed by 57 Fe Mössbauer spectrometry, which is highly sensitive to the presence of iron atoms in a compound [9]. Nevertheless, some Ce-based compounds yield a relatively high magnetic moment even if no iron is detected by Mössbauer spectrometry.…”

Mesoporous cerium oxide for fast degradation of aryl organophosphate flame retardant triphenyl phosphate

“…However, the temperature during calcination plays a crucial role in the surface properties (specic surface area, the presence of surface active sites), crystallinity, and other physicochemical characteristics. 17,20,21 In this work, we have tested the unique properties of cerium (III, IV) dioxides for fast and safe degradation of organophosphorus ame retardants in the environment using triphenyl phosphate (TPP) as a model compound. The sorbents prepared by our developed procedure are inexpensive and efficient in degradation of organophosphorus compounds.…”