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A stepwise loading method to magnetically responsive Pt-Fe3O 4/MCNT catalysts for selective hydrogenation of 3-methylcrotonaldehyde.

Song S, Yu J, Xiao Q, Ye X, Zhong Y, Zhu W - Nanoscale Res Lett (2014)

Bottom Line: A very high selectivity to 3-methylcrotonalcohol of 98% at a conversion of about 80% was available on the magnetic Pt-Fe3O4/MCNT catalyst.The magnetic catalyst, with good superparamagnetism, can be easily recovered from the liquid phase system under the external magnetic field.Moreover, both the Pt/MCNT and magnetic Pt-Fe3O4/MCNT catalysts show a good recyclability, confirmed by five cycles of reusage.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Institute of Physical Chemistry, Zhejiang Normal University, Jinhua, 321004, People's Republic of China, 454283594@qq.com.

ABSTRACT
Pt-loaded multi-walled carbon nanotubes (Pt/MCNTs) and magnetically responsive Pt-Fe3O4/MCNT catalysts were prepared by a stepwise loading of preformed Pt and Fe3O4 nanoparticles onto multi-walled carbon nanotubes (MCNTs). The structure, composition, and magnetism of the catalysts were characterized by X-ray diffraction (XRD), TEM, H2-O2 titration, inductively coupling plasma-atomic emission spectroscopy (ICP-AES), and superconducting quantum interference device (SQUID) techniques. Ascribed to the well-controlled particle size in the preformed Pt colloids, Pt particles in the consequent Pt/MCNT and Pt-Fe3O4/MCNT catalysts are of high uniformity and dispersion. The prepared Pt catalysts show an excellent catalytic performance in the liquid phase hydrogenation of 3-methylcrotonaldehyde, one of typical α,β-unsaturated aldehydes. A very high selectivity to 3-methylcrotonalcohol of 98% at a conversion of about 80% was available on the magnetic Pt-Fe3O4/MCNT catalyst. The magnetic catalyst, with good superparamagnetism, can be easily recovered from the liquid phase system under the external magnetic field. Moreover, both the Pt/MCNT and magnetic Pt-Fe3O4/MCNT catalysts show a good recyclability, confirmed by five cycles of reusage.

No MeSH data available.


TEM images of (A) 5Fe3O4/MCNT, (B, C) 3Pt-5Fe3O4/MCNT, and (D) EDS spectrum of 3Pt-5Fe3O4/MCNT.
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Fig6: TEM images of (A) 5Fe3O4/MCNT, (B, C) 3Pt-5Fe3O4/MCNT, and (D) EDS spectrum of 3Pt-5Fe3O4/MCNT.

Mentions: The TEM image of the magnetic composite (5Fe3O4/MCNT) reveals that Fe3O4 nanoparticles with diameter of about 2 to 4 nm are well dispersed on the outer surface of MCNTs (Figure 6A). While on the 3Pt-5Fe3O4/MCNT catalyst, some dark spots attributed to the Pt nanoparticles appear besides the grey spots of Fe3O4 nanoparticles (Figure 6B). From the magnified image (Figure 6C), one can see the highly dispersed Pt and Fe3O4 nanoparticles separately located on the surface. The high resolution TEM image shows that the nanoparticles are single crystalline, confirmed by atomic lattice fringes (Figure 6C, inset). For a grey spot, the distance between two planes is about 0.26 nm, in agreement with Fe3O4 (311) plane. While, for a dark spot, lattice spacing is about 0.23 nm, which can be attributed to the Pt (111) plane. Additionally, from the energy-dispersive X-ray spectroscopy (EDS), characteristic X-rays assigned to Fe and Pt elements can be observed, further confirming that Pt and Fe3O4 nanoparticles have been successfully supported on MCNT (Figure 6D).Figure 6


A stepwise loading method to magnetically responsive Pt-Fe3O 4/MCNT catalysts for selective hydrogenation of 3-methylcrotonaldehyde.

Song S, Yu J, Xiao Q, Ye X, Zhong Y, Zhu W - Nanoscale Res Lett (2014)

TEM images of (A) 5Fe3O4/MCNT, (B, C) 3Pt-5Fe3O4/MCNT, and (D) EDS spectrum of 3Pt-5Fe3O4/MCNT.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
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getmorefigures.php?uid=PMC4493847&req=5

Fig6: TEM images of (A) 5Fe3O4/MCNT, (B, C) 3Pt-5Fe3O4/MCNT, and (D) EDS spectrum of 3Pt-5Fe3O4/MCNT.
Mentions: The TEM image of the magnetic composite (5Fe3O4/MCNT) reveals that Fe3O4 nanoparticles with diameter of about 2 to 4 nm are well dispersed on the outer surface of MCNTs (Figure 6A). While on the 3Pt-5Fe3O4/MCNT catalyst, some dark spots attributed to the Pt nanoparticles appear besides the grey spots of Fe3O4 nanoparticles (Figure 6B). From the magnified image (Figure 6C), one can see the highly dispersed Pt and Fe3O4 nanoparticles separately located on the surface. The high resolution TEM image shows that the nanoparticles are single crystalline, confirmed by atomic lattice fringes (Figure 6C, inset). For a grey spot, the distance between two planes is about 0.26 nm, in agreement with Fe3O4 (311) plane. While, for a dark spot, lattice spacing is about 0.23 nm, which can be attributed to the Pt (111) plane. Additionally, from the energy-dispersive X-ray spectroscopy (EDS), characteristic X-rays assigned to Fe and Pt elements can be observed, further confirming that Pt and Fe3O4 nanoparticles have been successfully supported on MCNT (Figure 6D).Figure 6

Bottom Line: A very high selectivity to 3-methylcrotonalcohol of 98% at a conversion of about 80% was available on the magnetic Pt-Fe3O4/MCNT catalyst.The magnetic catalyst, with good superparamagnetism, can be easily recovered from the liquid phase system under the external magnetic field.Moreover, both the Pt/MCNT and magnetic Pt-Fe3O4/MCNT catalysts show a good recyclability, confirmed by five cycles of reusage.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Institute of Physical Chemistry, Zhejiang Normal University, Jinhua, 321004, People's Republic of China, 454283594@qq.com.

ABSTRACT
Pt-loaded multi-walled carbon nanotubes (Pt/MCNTs) and magnetically responsive Pt-Fe3O4/MCNT catalysts were prepared by a stepwise loading of preformed Pt and Fe3O4 nanoparticles onto multi-walled carbon nanotubes (MCNTs). The structure, composition, and magnetism of the catalysts were characterized by X-ray diffraction (XRD), TEM, H2-O2 titration, inductively coupling plasma-atomic emission spectroscopy (ICP-AES), and superconducting quantum interference device (SQUID) techniques. Ascribed to the well-controlled particle size in the preformed Pt colloids, Pt particles in the consequent Pt/MCNT and Pt-Fe3O4/MCNT catalysts are of high uniformity and dispersion. The prepared Pt catalysts show an excellent catalytic performance in the liquid phase hydrogenation of 3-methylcrotonaldehyde, one of typical α,β-unsaturated aldehydes. A very high selectivity to 3-methylcrotonalcohol of 98% at a conversion of about 80% was available on the magnetic Pt-Fe3O4/MCNT catalyst. The magnetic catalyst, with good superparamagnetism, can be easily recovered from the liquid phase system under the external magnetic field. Moreover, both the Pt/MCNT and magnetic Pt-Fe3O4/MCNT catalysts show a good recyclability, confirmed by five cycles of reusage.

No MeSH data available.