Synthesis and characterization of bimetallic gold-silver (Au-Ag) nanocatalyst via seed colloid technique / Nurafaliana Berahim

In the present study, unique catalysts of monometallic gold (Au), silver (Ag) and bimetallic gold-silver (Au-Ag) nanoparticles (NPs) were prepared with different size or diameters by the citrate-thermal reduction and the seed colloidal techniques, respectively. The catalytic nanoparticles were chara...

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Main Author: Nurafaliana, Berahim
Format: Thesis
Published: 2020
Subjects:
Online Access:http://studentsrepo.um.edu.my/12132/
http://studentsrepo.um.edu.my/12132/1/Nurafaliana_Berahim.jpg
http://studentsrepo.um.edu.my/12132/8/nurafaliana.pdf
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author Nurafaliana, Berahim
author_facet Nurafaliana, Berahim
author_sort Nurafaliana, Berahim
building UM Research Repository
collection Online Access
description In the present study, unique catalysts of monometallic gold (Au), silver (Ag) and bimetallic gold-silver (Au-Ag) nanoparticles (NPs) were prepared with different size or diameters by the citrate-thermal reduction and the seed colloidal techniques, respectively. The catalytic nanoparticles were characterized by various advanced analytical techniques such as Ultraviolet-visible spectroscopy (UV-vis), zeta potential, electron dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), High-angle annular dark-field (HAADF) scanning transmission-electron microscopy (STEM) imaging and the energy dispersive spectroscopy (EDS) elemental mapping. The catalytic performance of the nanoparticles were ascertained through the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the presence of sodium borohydride (NaBH4). The results of the study clearly showed that the rate of 4-NP reduction to 4-AP increased with a corresponding decrease in the size or diameter of the bimetallic NPs. The Au seed volume of 5.0 ml indicated relatively higher reduction rates as compared to that of 2.0 ml. However, the monometallic NPs showed relatively lesser catalytic activity in the reductive conversion of 4-NP to 4-AP. The catalytic properties of the bimetallic Au-Ag nanoparticles also reinforced with a direct impact of the size and composition of the bimetallic nanoparticles.
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spelling um-121322021-04-20T23:56:50Z Synthesis and characterization of bimetallic gold-silver (Au-Ag) nanocatalyst via seed colloid technique / Nurafaliana Berahim Nurafaliana, Berahim TA Engineering (General). Civil engineering (General) In the present study, unique catalysts of monometallic gold (Au), silver (Ag) and bimetallic gold-silver (Au-Ag) nanoparticles (NPs) were prepared with different size or diameters by the citrate-thermal reduction and the seed colloidal techniques, respectively. The catalytic nanoparticles were characterized by various advanced analytical techniques such as Ultraviolet-visible spectroscopy (UV-vis), zeta potential, electron dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), High-angle annular dark-field (HAADF) scanning transmission-electron microscopy (STEM) imaging and the energy dispersive spectroscopy (EDS) elemental mapping. The catalytic performance of the nanoparticles were ascertained through the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the presence of sodium borohydride (NaBH4). The results of the study clearly showed that the rate of 4-NP reduction to 4-AP increased with a corresponding decrease in the size or diameter of the bimetallic NPs. The Au seed volume of 5.0 ml indicated relatively higher reduction rates as compared to that of 2.0 ml. However, the monometallic NPs showed relatively lesser catalytic activity in the reductive conversion of 4-NP to 4-AP. The catalytic properties of the bimetallic Au-Ag nanoparticles also reinforced with a direct impact of the size and composition of the bimetallic nanoparticles. 2020-08 Thesis NonPeerReviewed application/pdf http://studentsrepo.um.edu.my/12132/1/Nurafaliana_Berahim.jpg application/pdf http://studentsrepo.um.edu.my/12132/8/nurafaliana.pdf Nurafaliana, Berahim (2020) Synthesis and characterization of bimetallic gold-silver (Au-Ag) nanocatalyst via seed colloid technique / Nurafaliana Berahim. Masters thesis, University of Malaya. http://studentsrepo.um.edu.my/12132/
spellingShingle TA Engineering (General). Civil engineering (General)
Nurafaliana, Berahim
Synthesis and characterization of bimetallic gold-silver (Au-Ag) nanocatalyst via seed colloid technique / Nurafaliana Berahim
title Synthesis and characterization of bimetallic gold-silver (Au-Ag) nanocatalyst via seed colloid technique / Nurafaliana Berahim
title_full Synthesis and characterization of bimetallic gold-silver (Au-Ag) nanocatalyst via seed colloid technique / Nurafaliana Berahim
title_fullStr Synthesis and characterization of bimetallic gold-silver (Au-Ag) nanocatalyst via seed colloid technique / Nurafaliana Berahim
title_full_unstemmed Synthesis and characterization of bimetallic gold-silver (Au-Ag) nanocatalyst via seed colloid technique / Nurafaliana Berahim
title_short Synthesis and characterization of bimetallic gold-silver (Au-Ag) nanocatalyst via seed colloid technique / Nurafaliana Berahim
title_sort synthesis and characterization of bimetallic gold-silver (au-ag) nanocatalyst via seed colloid technique / nurafaliana berahim
topic TA Engineering (General). Civil engineering (General)
url http://studentsrepo.um.edu.my/12132/
http://studentsrepo.um.edu.my/12132/1/Nurafaliana_Berahim.jpg
http://studentsrepo.um.edu.my/12132/8/nurafaliana.pdf