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Platinum Nanoparticles Functionalized with Ethynylphenylboronic Acid Derivatives: Selective Manipulation of Nanoparticle Photoluminescence by Fluoride Ions
journal contribution
posted on 2014-05-13, 00:00 authored by Peiguang Hu, Yang Song, Mauricio Daniel Rojas-Andrade, Shaowei ChenPlatinum
nanoparticles functionalized with 4-ethynylphenylboronic
acid pinacol ester (Pt–EPBAPE) were successfully synthesized
by a simple chemical reduction procedure. Because of the formation
of conjugated metal–ligand interfacial linkages, the resulting
nanoparticles exhibited apparent photoluminescence arising from the
nanoparticle-bound acetylene moieties that behaved analogously to
diacetylene derivatives. Interestingly, the nanoparticle photoluminescence
was markedly quenched upon the addition of fluoride ions (F–). In contrast, significantly less or virtually no change was observed
with a variety of other anions such as Cl–, Br–, I–, NO3–, HSO4–, H2PO4–, ClO4–, BF4–, and
PF6–. The high selectivity toward fluoride ion is most probably because
of the strong specific affinity of the boronic acid moiety to fluoride.
The formation of B–F bonds led to the conversion of Bsp2 to Bsp3, as manifested in 11B NMR measurements,
which impacted the intraparticle charge delocalization between the
particle-bound acetylene moieties and hence the nanoparticle photoluminescence.