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Title: Solvent Isotope Effects on the Creation of Fluorescent Quantum Defects in Carbon Nanotubes by Aryl Diazonium Chemistry
The integration of aryl diazonium and carbon nanotube chemistries has offered rich and versatile tools for creating nanomaterials of unique optical and electronic properties in a controllable fashion. The diazonium reaction with single-wall carbon nanotubes (SWCNTs) is known to proceed through a radical or carbocation mechanism in aqueous solutions, with deuterated water (D2O) being the frequently used solvent. Here, we show strong water solvent isotope effects on the aryl diazonium reaction with SWCNTs for creating fluorescent quantum defects using water (H2O) and D2O. We found a deduced reaction constant of ∼18.2 times larger value in D2O than in H2O, potentially due to their different chemical properties. We also observed the generation of new defect photoluminescence over a broad concentration range of diazonium reactants in H2O, as opposed to a narrow window of reaction conditions in D2O under UV excitation. Without UV light, the physical adsorption of diazonium on the surface of SWCNTs led to the fluorescence quenching of nanotubes. These findings provide important insights into the aryl diazonium chemistry with carbon nanotubes for creating promising material platforms for optical sensing, imaging, and quantum communication technologies.  more » « less
Award ID(s):
2142579
PAR ID:
10510954
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
ACS Publications
Date Published:
Journal Name:
Journal of the American Chemical Society
Volume:
145
Issue:
47
ISSN:
0002-7863
Page Range / eLocation ID:
25621 to 25631
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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