Assembly of Gold Nanoparticles into Chiral Superstructures Driven by Circularly Polarized Light

Abstract

Photon-to-matter chirality transfer offers both simplicity and universality to chiral synthesis but its efficiency is typically low for organic compounds. New pathways for imposing chiral bias during chemical process are essential for a variety of technologies from medicine to informatics as well as for fundamental science. Strong optical activity of inorganic nanoparticles (NPs) afford photosynthetic routes to chiral superstructures using circularly polarized photons. Plasmonic NPs are especially promising candidates for such reactions but realization and adequate interpretation of light-driven synthesis of chiral nanostructures in light-driven processes was more challenging than for semiconductor NPs. The process also requires unconventional approaches for the quantification of chiral products. Here we show that illumination of nanoscale colloidal dispersions with circularly polarized light induces the formation of chiral nanostructures 10-15 nm in diameter. Despite their seemingly irregular shape, the resulting nanocolloids showed circular dichroism (CD) spectra with opposite polarity after exposure to photons with left-and right circular polarization. The sign and spectral position of the experimental CD peaks of

Light-responsive self-assembly of semi-conducting nanoplatelets

“…6,7 Further, polarized incident light can also control their handedness. 8 The light-driven assembly of numerous nanoparticles has been investigated to date, however limited to spherical nanoparticles and to nanorods. 9,10,11,12 In parallel, new anisotropic nanoparticles have been synthesized and characterised and in particular, CdSe semi-conducting nanoplatelets with rectangular shapes.…”

Chiromagnetic Plasmonic Nanoassemblies with Magnetic Field Modulated Chiral Activity

“…Chirality is a universal feature of nature, and a chiral medium exhibits different absorption of right‐handed circularly polarized (RCP) and left‐handed circularly polarized (LCP) light . Numerous biomolecules display chirality, including nucleic acids, amino acids, proteins, and so on .…”

“…The emergence of chiral plasmonic nanomaterials has provided a new pathway for high chiral optical responses, especially in the visible or near‐infrared range, resulting from the collective plasmonic resonance coupling by metallic nanoparticles (NPs) . Great efforts have been made in the delicate design and construction of chiral plasmonic nanostructures, and other efforts have been devoted to the amplification and controllable modulation of the chiral optical signal . In recent years, a large number of chiroplasmonic nanostructures have been fabricated, with various components, sizes, geometries, and conformations, as well as assembly hierarchies .…”

Dynamic Spirals of Nanoparticles in Light‐Responsive Polygonal Fields

“…Promoting the self‐assembly of nano‐objects into larger, functional, dynamic materials in which the size‐related properties of these nano‐objects can be preserved, enhanced, and eventually controlled has become a contemporary field of investigations . Living systems offer compelling evidence that multiscale, sophisticated, and stimuli‐responsive architectures can be built simply by letting their smallest parts self‐organize, as dictated by their intrinsic properties.…”

“…Promoting the self-assembly of nano-objects into larger, functional, dynamic materials in which the size-related properties of these nano-objects can be preserved, enhanced, and eventually controlled has become a contemporary field of investigations. [1][2][3][4][5][6][7] Living systems offer compelling evidence that multiscale, sophisticated, and stimuli-responsive architectures can be built simply by letting their smallest parts self-organize, as dictated by their intrinsic properties. In particular, the templating of micro-and nano-inclusions to form hybrid materials is a well-known strategy employed by nature, [8] that has inspired the realization of hybrid optical materials.…”