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  • Influence of environmental conditions on the morphological evolution of bismuth oxide nanostructures via pulsed laser ablation in liquids
Title: Influence of environmental conditions on the morphological evolution of bismuth oxide nanostructures via pulsed laser ablation in liquids
Bismuth oxide nanomaterials are increasingly recognized for their promising electronic and optical properties, particularly in electrochemical and biomedical applications. This study demonstrates that various bismuth oxide nanostructures can be synthesized through pulsed laser ablation in liquids (PLAL) by adjusting the concentration of dissolved gases from ambient conditions. Structural and compositional analyses were performed using x-ray diffraction, Raman spectroscopy, FTIR spectroscopy, and morphological investigations were conducted using atomic force microscopy and transmission electron microscopy. Our findings indicate that factors such as dissolved gases, laser fluence, and nanoparticle aging are crucial in determining the final structure and composition of the resulting nanomaterial. The phases observed ranged from spherical metallic bismuth nanoparticles to monoclinic bismuth oxide nanowire bundles, and orthorhombic bismuth carbonate oxide nanosheets. Dissolved gases are shown to influence not only the primary particles formed immediately after ablation, but also significantly impact the aging process of the colloid as well. Additionally, fluence plays an important role in the production of reactive oxygen species, thereby influencing the reactive pathways experienced by the ablated material and its subsequent formation into nanostructures. A notable result, emphasizing the significance of factors such as liquid environment and fluence when performing PLAL on reactive targets like bismuth, is seen in high fluence (20 J/cm) samples under ambient conditions. These samples initially display an amalgamation of BiO nanowire bundles and carbonate nanosheets, which upon aging, transition to predominantly bismuth oxide nanowire bundles. This contrasts with samples produced in a saturated CO environment where bismuth carbonate nanosheets remain highly stable in the colloid.  more » « less
Award ID(s):
2213408 2117792
PAR ID:
10538297
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Colloids and Surfaces A: Physicochemical and Engineering Aspects
Volume:
690
Issue:
C
ISSN:
0927-7757
Page Range / eLocation ID:
133768
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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