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Cooperative Gold Nanoparticle Stabilization by Acetylenic Phosphaalkenes.

ABSTRACT: Acetylenic phosphaalkenes (APAs) are used as a novel type of ligands for the stabilization of gold nanoparticles (AuNP). As demonstrated by a variety of experimental and analytical methods, both structural features of the APA, that is, the P=C as well as the C?C units are essential for NP stabilization. The presence of intact APAs on the AuNP is demonstrated by surface-enhanced Raman spectroscopy (SERS), and first principle calculations indicate that bonding occurs most likely at defect sites on the Au surface. AuNP-bound APAs are in chemical equilibrium with free APAs in solution, leading to a dynamic behavior that can be explored for facile place-exchange reactions with other types of anchor groups such as thiols or more weakly binding phosphine ligands.

SUBMITTER: Orthaber A

PROVIDER: S-EPMC4557036 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature

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Cooperative Gold Nanoparticle Stabilization by Acetylenic Phosphaalkenes.

Orthaber Andreas A Löfås Henrik H Öberg Elisabet E Grigoriev Anton A Wallner Andreas A Jafri S Hassan M SH Santoni Marie-Pierre MP Ahuja Rajeev R Leifer Klaus K Ottosson Henrik H Ott Sascha S

Angewandte Chemie (International ed. in English) 20150723 36

Acetylenic phosphaalkenes (APAs) are used as a novel type of ligands for the stabilization of gold nanoparticles (AuNP). As demonstrated by a variety of experimental and analytical methods, both structural features of the APA, that is, the P=C as well as the C≡C units are essential for NP stabilization. The presence of intact APAs on the AuNP is demonstrated by surface-enhanced Raman spectroscopy (SERS), and first principle calculations indicate that bonding occurs most likely at defect sites on ...[more]

PMID: 26211907

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