American Journal of Nanomaterials
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American Journal of Nanomaterials. 2023, 11(1), 1-9
DOI: 10.12691/ajn-11-1-1
Open AccessArticle

Gold Nanoparticles Microwave-assisted Synthesis Employing Exclusively Ascorbic Acid as a Reducing and Stabilizing Agent: An Experimental and Computational Study

Ricardo Baez-Cruz1, 2, and Erik Beristain-Montiel3,

1Department of Physics, Faculty of Physical and Mathematical Science, University of Concepcion, PO-Box 160-C, Concepcion, Chile

2Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany

3Facultad de Quimica, Universidad Nacional Autonoma de Mexico, Coyoacan 04510, CDMX, Mexico

Pub. Date: January 20, 2023

Cite this paper:
Ricardo Baez-Cruz and Erik Beristain-Montiel. Gold Nanoparticles Microwave-assisted Synthesis Employing Exclusively Ascorbic Acid as a Reducing and Stabilizing Agent: An Experimental and Computational Study. American Journal of Nanomaterials. 2023; 11(1):1-9. doi: 10.12691/ajn-11-1-1


Using soft acids as reducing agents in synthesizing metallic nanoparticles have constituted a clear framework for achieving selected morphological properties with minimal toxicity. The system's complexity and the many variables involved represent a challenge for experimental studies desiring to design reproducible synthesis protocols. In this work, we explore the exclusion of any stabilizing agent to synthesize, in an aqueous solution, non-spherical gold nanoparticles (AuNPs) via Microwave-assisted synthesis, and instead, we employed pH control over reducing agent L-Ascorbic acid (AH2). The use of AH2 presents a direct approach that allows an understanding of the role of soft acids in synthesizing metallic nanoparticles. The results indicate that AuNPs synthesized at pH ≥ 10 exhibit relatively different morphologies than those obtained at higher pH values. The AuNPs were characterized via Transmission electron Microscopy and UV-Vis Spectroscopy. Our simulations reveal the plasmon distribution according to particle shape. The experimental analysis suggests that the pH variation mechanism over the reduction agent correlates with AuNPs geometry. These results indicate that pH is an applicable parameter for controlling the nanoparticle's geometry and extend the possibility of exploring computational studies on the impact of acids adsorbed on gold colloidal surfaces.

gold nanoparticles wet-synthesis L-Ascorbic acid TEM BEM

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