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Ferric Phosphate Hydroxide Microstructures Affect Their Magnetic Properties.

Zhao J, Zhang Y, Run Z, Li P, Guo Q, Pang H - ChemistryOpen (2015)

Bottom Line: Several ferric phosphate hydroxide (Fe4(OH)3(PO4)3) microstructures were successfully prepared under hydrothermal conditions.More importantly, the magnetic properties of these materials are directly correlated to their size and micro/nanostructure morphology.These crystals are good examples that prove that physical and chemical properties of nano/microstructured materials are related to their structures, and the precise control of the morphology of such functional materials could allow for the control of their performance.

View Article: PubMed Central - PubMed

Affiliation: College of Chemistry and Chemical Engineering, Anyang Normal University Anyang, Henan, 455002, P. R. China.

ABSTRACT
Uniformly sized and shape-controlled nanoparticles are important due to their applications in catalysis, electrochemistry, ion exchange, molecular adsorption, and electronics. Several ferric phosphate hydroxide (Fe4(OH)3(PO4)3) microstructures were successfully prepared under hydrothermal conditions. Using controlled variations in the reaction conditions, such as reaction time, temperature, and amount of hexadecyltrimethylammonium bromide (CTAB), the crystals can be grown as almost perfect hyperbranched microcrystals at 180 °C (without CTAB) or relatively monodisperse particles at 220 °C (with CTAB). The large hyperbranched structure of Fe4(OH)3(PO4)3 with a size of ∼19 μm forms with the "fractal growth rule" and shows many branches. More importantly, the magnetic properties of these materials are directly correlated to their size and micro/nanostructure morphology. Interestingly, the blocking temperature (T B) shows a dependence on size and shape, and a smaller size resulted in a lower T B. These crystals are good examples that prove that physical and chemical properties of nano/microstructured materials are related to their structures, and the precise control of the morphology of such functional materials could allow for the control of their performance.

No MeSH data available.


Related in: MedlinePlus

The sum of zero-field-cooled–field-cooled (ZFC–FC) temperature scan at 500 Oe for N1–N5.
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fig04: The sum of zero-field-cooled–field-cooled (ZFC–FC) temperature scan at 500 Oe for N1–N5.

Mentions: The magnetic properties of micro/nanomaterials are directly dependent on the size and shape of the particles. Understanding the correlation between micro/nanostructure and magnetic property is important for fundamental research, but also for the development of potential applications in electronic and information technologies. The size and shape-dependent magnetic properties of the five Fe4(OH)3(PO4)3 microcrystals (N1–N5) were studied using a superconducting quantum interference device (SQUID). Zero-field-cooled–field-cooled (ZFC–FC) temperature scanning at 500 Oe is shown in Figure 4 and Figure S1 in the Supporting Information. The five Fe4(OH)3(PO4)3 samples have ferrimagnetic behavior at low temperatures as shown in Figure 4. ZFC measurement was carried out, cooling from 300 to 1.8 K without any external magnetic field. Then a magnetic field of 500 Oe was applied, and the magnetization of the sample was measured following the rise in the temperature. When the temperature approaches a specific point, the magnetization reaches a maximum and then starts to decrease. The specific temperature point at which the thermal activation overcomes all the energy barriers is known as the blocking temperature (TB). Moreover, in the FC measurement, the sample was initially cooled to 1.8 K under an applied magnetic field of 500 Oe. The subsequent magnetization measurement was recorded from 1.8 to 300 K with the magnetic field kept at 500 Oe (Figure 4). The TB of as-prepared Fe4(OH)3(PO4)3 microcrystals is shown in Table 2. The biggest crystal, N3, has the highest TB (170.3 K) among the five, while the smallest crystal, N5, has the lowest one (75.5 K). It is interesting that the TB shows size and shape dependence, and that a smaller size results in a lower TB value. A similar behavior has been documented for other types of nanoparticles, for example, nickel and terbium.17–19


Ferric Phosphate Hydroxide Microstructures Affect Their Magnetic Properties.

Zhao J, Zhang Y, Run Z, Li P, Guo Q, Pang H - ChemistryOpen (2015)

The sum of zero-field-cooled–field-cooled (ZFC–FC) temperature scan at 500 Oe for N1–N5.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4522176&req=5

fig04: The sum of zero-field-cooled–field-cooled (ZFC–FC) temperature scan at 500 Oe for N1–N5.
Mentions: The magnetic properties of micro/nanomaterials are directly dependent on the size and shape of the particles. Understanding the correlation between micro/nanostructure and magnetic property is important for fundamental research, but also for the development of potential applications in electronic and information technologies. The size and shape-dependent magnetic properties of the five Fe4(OH)3(PO4)3 microcrystals (N1–N5) were studied using a superconducting quantum interference device (SQUID). Zero-field-cooled–field-cooled (ZFC–FC) temperature scanning at 500 Oe is shown in Figure 4 and Figure S1 in the Supporting Information. The five Fe4(OH)3(PO4)3 samples have ferrimagnetic behavior at low temperatures as shown in Figure 4. ZFC measurement was carried out, cooling from 300 to 1.8 K without any external magnetic field. Then a magnetic field of 500 Oe was applied, and the magnetization of the sample was measured following the rise in the temperature. When the temperature approaches a specific point, the magnetization reaches a maximum and then starts to decrease. The specific temperature point at which the thermal activation overcomes all the energy barriers is known as the blocking temperature (TB). Moreover, in the FC measurement, the sample was initially cooled to 1.8 K under an applied magnetic field of 500 Oe. The subsequent magnetization measurement was recorded from 1.8 to 300 K with the magnetic field kept at 500 Oe (Figure 4). The TB of as-prepared Fe4(OH)3(PO4)3 microcrystals is shown in Table 2. The biggest crystal, N3, has the highest TB (170.3 K) among the five, while the smallest crystal, N5, has the lowest one (75.5 K). It is interesting that the TB shows size and shape dependence, and that a smaller size results in a lower TB value. A similar behavior has been documented for other types of nanoparticles, for example, nickel and terbium.17–19

Bottom Line: Several ferric phosphate hydroxide (Fe4(OH)3(PO4)3) microstructures were successfully prepared under hydrothermal conditions.More importantly, the magnetic properties of these materials are directly correlated to their size and micro/nanostructure morphology.These crystals are good examples that prove that physical and chemical properties of nano/microstructured materials are related to their structures, and the precise control of the morphology of such functional materials could allow for the control of their performance.

View Article: PubMed Central - PubMed

Affiliation: College of Chemistry and Chemical Engineering, Anyang Normal University Anyang, Henan, 455002, P. R. China.

ABSTRACT
Uniformly sized and shape-controlled nanoparticles are important due to their applications in catalysis, electrochemistry, ion exchange, molecular adsorption, and electronics. Several ferric phosphate hydroxide (Fe4(OH)3(PO4)3) microstructures were successfully prepared under hydrothermal conditions. Using controlled variations in the reaction conditions, such as reaction time, temperature, and amount of hexadecyltrimethylammonium bromide (CTAB), the crystals can be grown as almost perfect hyperbranched microcrystals at 180 °C (without CTAB) or relatively monodisperse particles at 220 °C (with CTAB). The large hyperbranched structure of Fe4(OH)3(PO4)3 with a size of ∼19 μm forms with the "fractal growth rule" and shows many branches. More importantly, the magnetic properties of these materials are directly correlated to their size and micro/nanostructure morphology. Interestingly, the blocking temperature (T B) shows a dependence on size and shape, and a smaller size resulted in a lower T B. These crystals are good examples that prove that physical and chemical properties of nano/microstructured materials are related to their structures, and the precise control of the morphology of such functional materials could allow for the control of their performance.

No MeSH data available.


Related in: MedlinePlus