Quantitative Replacement of Citrate by Phosphane on Silver Nanoparticle Surfaces Monitored by Surface-Enhanced Raman Spectroscopy (SERS).
J Nanosci Nanotechnol
; 15(2): 1591-6, 2015 Feb.
Article
in En
| MEDLINE
| ID: mdl-26353696
ABSTRACT
Chemical approaches to metal NP synthesis commonly use capping agents to achieve a desired NP size and shape. Frequently, such NPs require chemically different surface ligands after synthesis to generate desired NP properties (e.g., charge or hydrophilicity) and to increase their long term colloidal stability. Here, we prepared SERS active citrate-stabilized silver NPs (d = 38±4 nm), purified them from remaining reactants by ultracentrifugation and redispersion, and immersed them into solutions containing different concentrations of Tris(sodium-m-sulfonatophenyl)phosphine (TPPTS), which is often used in such ligand replacement approaches to increase colloidal stability. After equilibration, SERS spectra were acquired, elucidating the concentration dependence of the ligand replacement reaction. SERS data were complemented by concentration dependent size measurements and relations between ligand exchange and colloidal stability are discussed.
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Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
J Nanosci Nanotechnol
Year:
2015
Document type:
Article