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Title: Understanding photochemical pathways of laser-induced metal ion reduction through byproduct analysis
Laser-induced reduction of metal ions is attracting increasing attention as a sustainable route to ligand-free metal nanoparticles. In this work, we investigate the photochemical reactions involved in reduction of Ag + and [AuCl 4 ] − upon interaction with lasers with nanosecond and femtosecond pulse duration, using strong-field ionization mass spectrometry and spectroscopic assays to identify stable molecular byproducts. Whereas Ag + in aqueous isopropyl alcohol (IPA) is reduced through plasma-mediated mechanisms upon femtosecond laser excitation, low-fluence nanosecond laser excitation induces electron transfer from IPA to Ag + . Both nanosecond and femtosecond laser excitation of aqueous [AuCl 4 ] − produce reactive chlorine species by Au–Cl bond homolysis. Formation of numerous volatile products by IPA decomposition during both femtosecond and nanosecond laser excitation of [AuCl 4 ] − is attributed to enhanced optical breakdown by the Au nanoparticle products of [AuCl 4 ] − reduction. These mechanistic insights can inform the design of laser synthesis procedures to improve control over metal nanoparticle properties and enhance byproduct yields.  more » « less
Award ID(s):
1900094
PAR ID:
10437476
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Physical Chemistry Chemical Physics
Volume:
25
Issue:
28
ISSN:
1463-9076
Page Range / eLocation ID:
18844 to 18853
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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