Limits...
Preparation of stable magnetic nanofluids containing Fe3O4@PPy nanoparticles by a novel one-pot route.

Zhao B, Nan Z - Nanoscale Res Lett (2011)

Bottom Line: Trisodium citrate (Na3cit) was used as the reducing reagent to form Fe3O4 NPs.The Fe3O4@PPy NPs can still keep dispersing well after the nanofluid has been standing for 1 month and no sedimentation is found.The as-prepared Fe3O4@PPy NPs exhibit superparamagnetic behavior.

View Article: PubMed Central - HTML - PubMed

Affiliation: College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, 225002, People's Republic of China. zdnan@yzu.edu.cn.

ABSTRACT
Stable magnetic nanofluids containing Fe3O4@Polypyrrole (PPy) nanoparticles (NPs) were prepared by using a facile and novel method, in which one-pot route was used. FeCl3·6H2O was applied as the iron source, and the oxidizing agent to produce PPy. Trisodium citrate (Na3cit) was used as the reducing reagent to form Fe3O4 NPs. The as-prepared nanofluid can keep long-term stability. The Fe3O4@PPy NPs can still keep dispersing well after the nanofluid has been standing for 1 month and no sedimentation is found. The polymerization reaction of the pyrrole monomers took place with Fe3+ ions as the initiator, in which these Fe3+ ions remained in the solution adsorbed on the surface of the Fe3O4 NPs. Thus, the core-shell NPs of Fe3O4@PPy were obtained. The particle size of the as-prepared Fe3O4@PPy can be easily controlled from 7 to 30 nm by the polymerization reaction of the pyrrole monomers. The steric stabilization and weight of the NPs affect the stability of the nanofluids. The as-prepared Fe3O4@PPy NPs exhibit superparamagnetic behavior.

No MeSH data available.


Related in: MedlinePlus

TEM images of the Fe3O4@PPy precipitates collected by magnetic separation from the nanofluids prepared under different amounts of pyrrole monomer at 160°C: (A) 0.1 mL, (B) 0.3 mL, (C) 0.5 mL.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3211289&req=5

Figure 4: TEM images of the Fe3O4@PPy precipitates collected by magnetic separation from the nanofluids prepared under different amounts of pyrrole monomer at 160°C: (A) 0.1 mL, (B) 0.3 mL, (C) 0.5 mL.

Mentions: The size and shape of the precipitates were determined by TEM. Figure 4 presents the typical TEM images of the precipitates produced under various amounts of pyrrole monomer. All of these precipitates present uniform sizes and morphologies. Figure 4a shows the Fe3O4@PPy NPs prepared with 0.1 mL pyrrole monomer with an average diameter of 15 nm. When the amount of pyrrole monomer is 0.3 mL, the mean diameter of the NPs is about 7 nm as shown in Figure 4b. When the amount of pyrrole is increased to 0.5 mL, the average diameter of the NPs is about 70 nm as shown in Figure 4c. Core-shell structures can be found in Figure 4a, especially in Figure 4c. This kind structure was not clearly found in Figure 4b because of small particles produced in the experimental conditions. In order to study the structure of the sample shown in Figure 4b, a magnified figure was applied. Figure 5 shows the magnified image of the sample synthesized with 0.3 mL pyrrole, in which core-shell structure was clearly found (as arrows' directions). The corresponding SAED pattern as the inset in Figure 5 shows amorphous phase. Based on the result obtained from Figure 2b, Fe3O4 was produced. Thus, we thought that Fe3O4 NPs were coated by amorphous PPy. These results demonstrated that Fe3O4@PPy NPs were obtained in the present conditions. At the same time, the formation of PPy affected the growth of Fe3O4 NPs as shown in Figure 4. When the amount of pyrrole monomer is small, such as 0.1 mL pyrrole added into the reaction system, the formation rate of the PPy is slower and the shell of PPy is thinner than those produced with higher amounts of the pyrrole, such as 0.3 and 0.5 mL pyrrole. The Fe3O4 NPs grow quickly with small amounts of pyrrole. When the amount of pyrrole monomer is too high, such as 0.5 mL pyrrole added into the reaction system, the formation rate of the PPy is faster and the shell of PPy is thicker than those produced with smaller amounts of the pyrrole. The particle size becomes bigger because of the formation of the thick PPy shell. This kind of shell can be clearly found in Figure 4c. When the amount of the pyrrole was 0.3 mL, the size of the as-produced particle is the smallest in the present experimental conditions.


Preparation of stable magnetic nanofluids containing Fe3O4@PPy nanoparticles by a novel one-pot route.

Zhao B, Nan Z - Nanoscale Res Lett (2011)

TEM images of the Fe3O4@PPy precipitates collected by magnetic separation from the nanofluids prepared under different amounts of pyrrole monomer at 160°C: (A) 0.1 mL, (B) 0.3 mL, (C) 0.5 mL.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3211289&req=5

Figure 4: TEM images of the Fe3O4@PPy precipitates collected by magnetic separation from the nanofluids prepared under different amounts of pyrrole monomer at 160°C: (A) 0.1 mL, (B) 0.3 mL, (C) 0.5 mL.
Mentions: The size and shape of the precipitates were determined by TEM. Figure 4 presents the typical TEM images of the precipitates produced under various amounts of pyrrole monomer. All of these precipitates present uniform sizes and morphologies. Figure 4a shows the Fe3O4@PPy NPs prepared with 0.1 mL pyrrole monomer with an average diameter of 15 nm. When the amount of pyrrole monomer is 0.3 mL, the mean diameter of the NPs is about 7 nm as shown in Figure 4b. When the amount of pyrrole is increased to 0.5 mL, the average diameter of the NPs is about 70 nm as shown in Figure 4c. Core-shell structures can be found in Figure 4a, especially in Figure 4c. This kind structure was not clearly found in Figure 4b because of small particles produced in the experimental conditions. In order to study the structure of the sample shown in Figure 4b, a magnified figure was applied. Figure 5 shows the magnified image of the sample synthesized with 0.3 mL pyrrole, in which core-shell structure was clearly found (as arrows' directions). The corresponding SAED pattern as the inset in Figure 5 shows amorphous phase. Based on the result obtained from Figure 2b, Fe3O4 was produced. Thus, we thought that Fe3O4 NPs were coated by amorphous PPy. These results demonstrated that Fe3O4@PPy NPs were obtained in the present conditions. At the same time, the formation of PPy affected the growth of Fe3O4 NPs as shown in Figure 4. When the amount of pyrrole monomer is small, such as 0.1 mL pyrrole added into the reaction system, the formation rate of the PPy is slower and the shell of PPy is thinner than those produced with higher amounts of the pyrrole, such as 0.3 and 0.5 mL pyrrole. The Fe3O4 NPs grow quickly with small amounts of pyrrole. When the amount of pyrrole monomer is too high, such as 0.5 mL pyrrole added into the reaction system, the formation rate of the PPy is faster and the shell of PPy is thicker than those produced with smaller amounts of the pyrrole. The particle size becomes bigger because of the formation of the thick PPy shell. This kind of shell can be clearly found in Figure 4c. When the amount of the pyrrole was 0.3 mL, the size of the as-produced particle is the smallest in the present experimental conditions.

Bottom Line: Trisodium citrate (Na3cit) was used as the reducing reagent to form Fe3O4 NPs.The Fe3O4@PPy NPs can still keep dispersing well after the nanofluid has been standing for 1 month and no sedimentation is found.The as-prepared Fe3O4@PPy NPs exhibit superparamagnetic behavior.

View Article: PubMed Central - HTML - PubMed

Affiliation: College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, 225002, People's Republic of China. zdnan@yzu.edu.cn.

ABSTRACT
Stable magnetic nanofluids containing Fe3O4@Polypyrrole (PPy) nanoparticles (NPs) were prepared by using a facile and novel method, in which one-pot route was used. FeCl3·6H2O was applied as the iron source, and the oxidizing agent to produce PPy. Trisodium citrate (Na3cit) was used as the reducing reagent to form Fe3O4 NPs. The as-prepared nanofluid can keep long-term stability. The Fe3O4@PPy NPs can still keep dispersing well after the nanofluid has been standing for 1 month and no sedimentation is found. The polymerization reaction of the pyrrole monomers took place with Fe3+ ions as the initiator, in which these Fe3+ ions remained in the solution adsorbed on the surface of the Fe3O4 NPs. Thus, the core-shell NPs of Fe3O4@PPy were obtained. The particle size of the as-prepared Fe3O4@PPy can be easily controlled from 7 to 30 nm by the polymerization reaction of the pyrrole monomers. The steric stabilization and weight of the NPs affect the stability of the nanofluids. The as-prepared Fe3O4@PPy NPs exhibit superparamagnetic behavior.

No MeSH data available.


Related in: MedlinePlus