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Preparation of Silver-Palladium Alloyed Nanoparticles for Plasmonic Catalysis under Visible-Light Illumination
Published on: August 18, 2020
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Silver-Nanoparticles Embedded Pyridine-Cholesterol Xerogels as Highly Efficient Catalysts for 4-Nitrophenol Reduction
Ganesh Shimoga1, Eun-Jae Shin1, Sang-Youn Kim1
1Interaction Laboratory of Advanced Technology Research Center, Korea University of Technology and Education, Cheonan-si, Chungcheongnam-do 330-708, Korea.
Materials (Basel, Switzerland)
|March 29, 2020
Summary
Silver-nanocomposites (SNCs) based on 4-pyridyl cholesterol (PC) xerogels efficiently catalyze the reduction of 4-nitrophenol to 4-aminophenol. These recyclable catalysts demonstrate high conversion efficiency and stability over multiple runs.
Area of Science:
- Materials Science
- Nanotechnology
- Catalysis
Background:
- 4-pyridyl cholesterol (PC) is a gelator capable of forming xerogels.
- Silver nanoparticles (SNPs) exhibit catalytic properties.
- The reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) is an important chemical transformation.
Purpose of the Study:
- To synthesize and characterize silver-nanocomposites (SNCs) based on PC xerogels.
- To investigate the catalytic efficiency of these SNC-PC xerogels for the reduction of 4-NP to 4-AP.
- To evaluate the recyclability and stability of the synthesized catalysts.
Main Methods:
- Preparation of silver-loaded PC xerogels using trisodium citrate dehydrate.
- Characterization using FE-SEM, FTIR, TGA, XRD, and UV-Vis spectroscopy.
- Catalytic evaluation of 4-NP reduction in the presence of sodium borohydride.
Main Results:
- FE-SEM confirmed spherical SNPs with sizes ranging from 30-80 nm embedded in the xerogel matrix.
- SNC-PC xerogels exhibited significant catalytic activity for 4-NP reduction.
- Recyclable conversion efficiency reached approximately 82% after four runs.
- Apparent rate constants (kapp) were determined for the catalytic reactions.
Conclusions:
- The synthesized SNC-PC xerogels are effective and recyclable catalysts for the reduction of 4-nitrophenol.
- The materials show promise for applications in green chemistry and catalysis.
- The study highlights the potential of nanocomposite xerogels for chemical transformations.
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