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antibacterial properties of the nanofiber mats against gram-negative (E. coli) and
gram-positive (S. aureus) were finally evaluated. These hydroxypropyl-βcyclodextrin/Ag nanoparticles composite nanofibers showed antibacterial activities,
and it was directly due to the presence of Ag nanoparticles in the nanofiber mats.
The same strategy was considered by the same team for the incorporation of Pd
nanoparticles into cyclodextrin nanofibers which were used for the catalytic reduction of nitroarene (Celebioglu et al. 2019a). These nanocomposite nanofibers were
prepared by electrospinning a hydroxypropyl-β-cyclodextrin solution containing
Pd(OAc) 2 as palladium precursor. Hydroxypropyl-β-cyclodextrin played the role of
reducing agent of the palladium source and was very important in order to manufacture the electrospun nanofibers. Different parameters such as the Pd loading and the
nature of the solvent were studied. These composite nanofibers were fully characterized by FTIR, transmission electron microscopy, scanning electron microscopy,
and X-ray photoelectron spectroscopy. Pd nanoparticles were homogeneously dispersed into and onto the nanofibers with mean diameter ranging from 3.7 and 4.9 nm
depending on the nature of the solvent or the Pd loading. These nanofibers containing Pd nanoparticles were catalytically active in the reduction of 4-nitrophenol into
4-aminophenol with turnover frequency ranging from 10.17 h
−1
to 12.25 h
−1
. The
authors clearly showed the multiple role of hydroxypropyl-β-cyclodextrin for the
preparation of these catalytic nanofibers; it means the role of reducing agent of palladium metal precursor, the role of stabilizing agent of Pd nanoparticles, and also
the role of handy nanofibrous carrier matrix.
Another strategy has been developed by the same team and consisted into the
production of cyclodextrin nanofibers by the electrospinning of an aqueous solution
of hydroxypropyl-β-cyclodextrin containing a multifunctional cross-linker
(1,2,3,4-butanetetracarboxylic acid, BTCA) in order to improve the robustness of the
nanofibers. After manufacturing of these poly-cyclodextrin nanowebs, Pd nanoparticles were supported onto this material by atomic layer deposition (Celebioglu et al.
2017). Transmission electron microscopy measurements clearly showed that Pd
nanoparticles were homogeneously dispersed onto the nanofiber mats with a mean
diameter centered on 4.34 nm. These nanofibers were used for the catalytic reduction
of 4-nitrophenol which was completely converted into 4- aminophenol within 35 min.
The reusability of these catalytic nanofibers was also studied, and it was possible to
reuse the Pd nanoparticles deposited onto electrospun nanofibers during five successive runs without any loss of activity which clearly showed that the Pd nanoparticles
were strongly anchored onto the poly-cyclodextrin nanowebs.
Yi et al. (2013) employed β-cyclodextrin for modification of multiwalled carbon
nanotubes (MWCNT) immobilized on Ti plates to prepare a novel electrode on
which binary Pd-Ni nanoparticles were electrodeposited. It was confirmed that
incorporation of β-cyclodextrin could improve the dispersion of nanoparticles and
led to nanoparticles with smaller sizes compared with the material without
β-cyclodextrin. The authors studied the electrocatalytic performance of the electrode
for alcohol electrooxidation and compared it with those of PdNi/MWCNT/Ti and
PdNi/Ti. The results established the superior electrocatalytic activity of the former.
S. Noël et al.
antibacterial properties of the nanofiber mats against gram-negative (E. coli) and
gram-positive (S. aureus) were finally evaluated. These hydroxypropyl-βcyclodextrin/Ag nanoparticles composite nanofibers showed antibacterial activities,
and it was directly due to the presence of Ag nanoparticles in the nanofiber mats.
The same strategy was considered by the same team for the incorporation of Pd
nanoparticles into cyclodextrin nanofibers which were used for the catalytic reduction of nitroarene (Celebioglu et al. 2019a). These nanocomposite nanofibers were
prepared by electrospinning a hydroxypropyl-β-cyclodextrin solution containing
Pd(OAc) 2 as palladium precursor. Hydroxypropyl-β-cyclodextrin played the role of
reducing agent of the palladium source and was very important in order to manufacture the electrospun nanofibers. Different parameters such as the Pd loading and the
nature of the solvent were studied. These composite nanofibers were fully characterized by FTIR, transmission electron microscopy, scanning electron microscopy,
and X-ray photoelectron spectroscopy. Pd nanoparticles were homogeneously dispersed into and onto the nanofibers with mean diameter ranging from 3.7 and 4.9 nm
depending on the nature of the solvent or the Pd loading. These nanofibers containing Pd nanoparticles were catalytically active in the reduction of 4-nitrophenol into
4-aminophenol with turnover frequency ranging from 10.17 h
−1
to 12.25 h
−1
. The
authors clearly showed the multiple role of hydroxypropyl-β-cyclodextrin for the
preparation of these catalytic nanofibers; it means the role of reducing agent of palladium metal precursor, the role of stabilizing agent of Pd nanoparticles, and also
the role of handy nanofibrous carrier matrix.
Another strategy has been developed by the same team and consisted into the
production of cyclodextrin nanofibers by the electrospinning of an aqueous solution
of hydroxypropyl-β-cyclodextrin containing a multifunctional cross-linker
(1,2,3,4-butanetetracarboxylic acid, BTCA) in order to improve the robustness of the
nanofibers. After manufacturing of these poly-cyclodextrin nanowebs, Pd nanoparticles were supported onto this material by atomic layer deposition (Celebioglu et al.
2017). Transmission electron microscopy measurements clearly showed that Pd
nanoparticles were homogeneously dispersed onto the nanofiber mats with a mean
diameter centered on 4.34 nm. These nanofibers were used for the catalytic reduction
of 4-nitrophenol which was completely converted into 4- aminophenol within 35 min.
The reusability of these catalytic nanofibers was also studied, and it was possible to
reuse the Pd nanoparticles deposited onto electrospun nanofibers during five successive runs without any loss of activity which clearly showed that the Pd nanoparticles
were strongly anchored onto the poly-cyclodextrin nanowebs.
Yi et al. (2013) employed β-cyclodextrin for modification of multiwalled carbon
nanotubes (MWCNT) immobilized on Ti plates to prepare a novel electrode on
which binary Pd-Ni nanoparticles were electrodeposited. It was confirmed that
incorporation of β-cyclodextrin could improve the dispersion of nanoparticles and
led to nanoparticles with smaller sizes compared with the material without
β-cyclodextrin. The authors studied the electrocatalytic performance of the electrode
for alcohol electrooxidation and compared it with those of PdNi/MWCNT/Ti and
PdNi/Ti. The results established the superior electrocatalytic activity of the former.
S. Noël et al.