It is essential to immobilize gold nanoparticles (AuNPs)
firmly
onto a certain substrate in a closely packed manner to apply plasmonic
functions of AuNP in photonic/electronic devices. AuNP-Si systems
are of particular interest for the integration of plasmonics to semiconductor
electronics. Here we report on the arrangement of AuNPs into a 2-D
array that was covalently bonded to a Si substrate without surface
oxide. This process was achieved by simply irradiating visible light
to a hydogen-terminated Si substrate immersed in a solution of AuNPs
covered with a self-assembled monolayer (SAM) of 11-mercaptoundecene
(MUD). These MUD-AuNPs were attached to the substrate by forming Si–C
bonds as a result of the photochemical reaction between Si–H
groups on the substrate and vinyl groups of the MUD-SAMs. The reaction
proceeded most effectively at a wavelength band around 520 nm adjusted
to the plasmonic resonance peak of the MUD-AuNPs(20 nm in diameter)/toluene
solution centered at 535 nm, demonstrating that the photochemical
reaction was assisted by localized surface plasmon, which allowed
the AuNPs to be photon collectors.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.