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3D-macroporous chitosan-based scaffolds with in situ formed Pd and Pt nanoparticles for nitrophenol reduction

Berillo, Dmitriy LU and Cundy, Andrew (2018) In Carbohydrate Polymers 192. p.166-175
Abstract

3D-macroporous chitosan-based scaffolds (cryogels) were produced via growth of metal-polymer coordinated complexes and electrostatic interactions between oppositely charged groups of chitosan and metal ions under subzero temperatures. A mechanism of reduction of noble metal complexes inside the cryogel walls by glutaraldehyde is proposed, which produces discrete and dispersed noble metal nanoparticles. 3D-macroporous scaffolds prepared under different conditions were characterised using TGA, FTIR, nitrogen adsorption, SEM, EDX and TEM, and the distribution of platinum nanoparticles (PtNPs) and palladium nanoparticles (PdNPs) in the material assessed. The catalytic activity of the in situ synthesised PdNPs, at 2.6, 12.5 and 21.0 μg total... (More)

3D-macroporous chitosan-based scaffolds (cryogels) were produced via growth of metal-polymer coordinated complexes and electrostatic interactions between oppositely charged groups of chitosan and metal ions under subzero temperatures. A mechanism of reduction of noble metal complexes inside the cryogel walls by glutaraldehyde is proposed, which produces discrete and dispersed noble metal nanoparticles. 3D-macroporous scaffolds prepared under different conditions were characterised using TGA, FTIR, nitrogen adsorption, SEM, EDX and TEM, and the distribution of platinum nanoparticles (PtNPs) and palladium nanoparticles (PdNPs) in the material assessed. The catalytic activity of the in situ synthesised PdNPs, at 2.6, 12.5 and 21.0 μg total mass, respectively, was studied utilising a model system of 4-nitrophenol reduction. The kinetics of the reaction under different conditions (temperature, concentration of catalyst) were examined, and a decrease of catalytic activity was not observed over 17 treatment cycles. Increasing the temperature of the catalytic reaction from 10 to 22 and 35 °C by PdNPs supported within the cryogel increased the kinetic rate by 44 and 126%, respectively. Turnover number and turnover frequency of the PdNPs catalysts at room temperature were in the range 0.20–0.53 h−1. The conversion degree of 4-nitrophenol at room temperature reached 98.9% (21.0 μg PdNPs). Significantly less mass of palladium nanoparticles (by 30–40 times) was needed compared to published data to obtain comparable rates of reduction of 4-nitrophenol.

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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Catalysis, Chitosan, Macroporous cryogels, Nitrophenol, Palladium nanoparticles, Platinum nanoparticles
in
Carbohydrate Polymers
volume
192
pages
10 pages
publisher
Elsevier
external identifiers
  • scopus:85044474603
ISSN
0144-8617
DOI
10.1016/j.carbpol.2018.03.038
language
English
LU publication?
yes
id
3cb8cbe5-1411-4ab2-94b0-91fae2c6b679
date added to LUP
2018-05-03 07:43:51
date last changed
2019-03-19 03:54:00
@article{3cb8cbe5-1411-4ab2-94b0-91fae2c6b679,
  abstract     = {<p>3D-macroporous chitosan-based scaffolds (cryogels) were produced via growth of metal-polymer coordinated complexes and electrostatic interactions between oppositely charged groups of chitosan and metal ions under subzero temperatures. A mechanism of reduction of noble metal complexes inside the cryogel walls by glutaraldehyde is proposed, which produces discrete and dispersed noble metal nanoparticles. 3D-macroporous scaffolds prepared under different conditions were characterised using TGA, FTIR, nitrogen adsorption, SEM, EDX and TEM, and the distribution of platinum nanoparticles (PtNPs) and palladium nanoparticles (PdNPs) in the material assessed. The catalytic activity of the in situ synthesised PdNPs, at 2.6, 12.5 and 21.0 μg total mass, respectively, was studied utilising a model system of 4-nitrophenol reduction. The kinetics of the reaction under different conditions (temperature, concentration of catalyst) were examined, and a decrease of catalytic activity was not observed over 17 treatment cycles. Increasing the temperature of the catalytic reaction from 10 to 22 and 35 °C by PdNPs supported within the cryogel increased the kinetic rate by 44 and 126%, respectively. Turnover number and turnover frequency of the PdNPs catalysts at room temperature were in the range 0.20–0.53 h<sup>−1</sup>. The conversion degree of 4-nitrophenol at room temperature reached 98.9% (21.0 μg PdNPs). Significantly less mass of palladium nanoparticles (by 30–40 times) was needed compared to published data to obtain comparable rates of reduction of 4-nitrophenol.</p>},
  author       = {Berillo, Dmitriy and Cundy, Andrew},
  issn         = {0144-8617},
  keyword      = {Catalysis,Chitosan,Macroporous cryogels,Nitrophenol,Palladium nanoparticles,Platinum nanoparticles},
  language     = {eng},
  month        = {07},
  pages        = {166--175},
  publisher    = {Elsevier},
  series       = {Carbohydrate Polymers},
  title        = {3D-macroporous chitosan-based scaffolds with in situ formed Pd and Pt nanoparticles for nitrophenol reduction},
  url          = {http://dx.doi.org/10.1016/j.carbpol.2018.03.038},
  volume       = {192},
  year         = {2018},
}