Broad Chiroptical Activity from Ultraviolet to Short-Wave Infrared by Chirality Transfer from Molecular to Micrometer Scale

Abstract

Chiral nanomaterials provide a rich platform for versatile applications. Tuning the wavelength of polarization rotation maxima in the broad range including short-wave infrared (SWIR) is a promising candidate for infrared neural stimulation, imaging, and nanothermometry. However, the majority of previously developed chiral nanomaterials reveal the optical activity in a relatively shorter wavelength range (ultraviolet−visible, UV−vis), not in SWIR. Here, we demonstrate a versatile method to synthesize chiral copper sulfides using cysteine, as the stabilizer, and transferring the chirality from molecular-to the microscale through self-assembly. The assembled structures show broad chiroptical activity in the UV− vis-NIR-SWIR region (200−2500 nm). Importantly, we can tune the chiroptical activity by simply changing the reaction conditions. This approach can be extended to materials platforms for developing next-generation optical devices, metamaterials, telecommunications, and asymmetric catalysts.

Field-Free Magnetoplasmon-Induced Ultraviolet Circular Dichroism Switching in Premagnetized Magnetic Nanowires

“…The CD effect could be obtained using a nonmagnetic OC nanostructure; however, the effect caused by such a structure is not easy to further manipulate using an external stimulus. − In this work, a type of CD that merits investigation is the combination of NM with magnetic materials. The magnetic field-tunable CD is useful for many MO applications, and so is the magnetoplasmonic effect for applications in biosensing, drug delivery, and others. , Regarding the practical applications of UV CD in nanostructures, where an NM and a magnetic material are introduced, determination of the matched light excitation (energy or frequency) and reduction of the external magnetic field are recommended.…”

“…Consequently, characterizing OC commonly involves discussing circular dichroism (CD). Most related studies have focused on manipulating CD at energies ranging from the near-infrared spectrum to the visible light spectrum. − However, studies on the CD effect have begun examining the ultraviolet (UV) domain − and the examination of UV CD is applicable to national defense and bioscience industries.…”

Chiral Mesostructured Carbonate with Vibrational Circular Dichroism

“…[12] Multiple OAs including both scatteringand absorption-based OAs were observed in chiral inorganic films that consisting of ZnO, [12] CuO, [13] NiO, [14] Fe 3 O 4 , [15] BiOBr, [16] silver, [17] gold, [18] and hydroxyapatite. [19] However, the absorption-based OAs are limited in plasmonic absorption of chiral metallic nanomaterials [20] and electron transition absorption of chiral semiconductors at ultraviolet-visible (UV-vis) [21] and near-infrared region, [22] although the response wavelength could be tunable depending on the composition of binary or ternary species. [23] As a common phenomenon, vibrational circular dichroism (VCD) has been widely applied in chiral organic materials, which arising from the selective vibrational absorption of L-and R-CP photons at the infrared (IR) region.…”

Chirality Analysis for Nanostructured Microparticles Using Deep Learning

“…The unique optical, biological, and electrical properties of chiral nanostructured particles strongly depend on the helicity of their nano-, meso,-and microscale shapes. [1][2][3][4][5][6][7] Unlike similarlysized chiral objects of (bio)organic origin, the shapes of chiral inorganic particles can be readily identified from electron microscopy (EM) images, which markedly streamlines the research process. However, the chiral nanostructures are polydispersed, necessitating simultaneous assessment of their chirality, size, shape, and variability.…”