Tsz Him Chow

CIC biomaGUNE · Bionanoplasmonics

The interference between spectrally overlapping superradiant and subradiant plasmon resonances generates plasmonic Fano resonance, which allows for attractive applications such as electromagnetically induced transparency, light trapping, and refractometric sensing with high figures of merit. The active switching of plasmonic Fano resonance holds gr...

Gold nanorings are attractive as plasmonic metal nanocrystals because they have a hollow inner cavity. Their enhanced electric field inside the ring cavity is accessible, which is highly desirable for assembling with other optical components and studying their plasmon‐coupling behaviors. However, the lack of robust methods for synthesizing size‐con...

Plasmonic color generation has attracted much research interest due to the unique optical properties of plasmonic nanocrystals that are promising for chromatic applications, such as flat-panel displays, smart windows and wearable devices. Low-cost, monodisperse plasmonic nanocrystals supporting strong localized surface plasmon resonances are favora...

Plasmonic colors produced by metallic metasurfaces show subwavelength spatial resolution, material simplicity and durability. Compared to the colors created by plasmonic metasurfaces, plasmonic colors generated by colloidal plas-monic nanostructures are of narrower spectral linewidths, sharper and purer chromaticity. However, difficulties in the ac...

Circular polarization-resolved Raman scattering methods include Raman optical activity (ROA) and its derivative—surface-enhanced Raman optical activity (SEROA). These spectroscopic modalities are rapidly developing due to their high information content, stand-off capabilities, and rapid development of Raman-active chiral nanostructures. These metho...

Transferring traditional plasmonic noble metal nanomaterials from the laboratory to industrial production has remained challenging due to the high price of noble metals. The development of cost-effective non-noble-metal alternatives with outstanding plasmonic properties has therefore become essential. Herein, we report on the gram-scale production...

We report on deep-to-near-UV transient absorption spectra of core-shell Au / SiO 2 and Au / TiO 2 nanoparticles (NPs) excited at the surface plasmon resonance of the Au core, and of UV-excited bare anatase TiO 2 NPs. The bleaching of the first excitonic transition of anatase TiO 2 at ∼3.8 eV is a signature of the presence of electrons/holes in the...

We present ultrafast spectroscopic investigations of the coherent acoustic vibrations of Au/SiO 2 and Au/TiO 2 core–shell nanoparticles (NPs) upon excitation of the Au surface plasmon resonance. The oscillations are detected in the region of the interband transitions of Au in the deep-ultraviolet, where they appear in the form of intensity modulati...

Plasmonic hot electrons have shown great potential in photocatalysis, but little is known about the hot hole-driven chemical reactions due to the lack of desired plasmonic metal/p-type semiconductor architectures. Herein, we describe a general and robust strategy for the site-selective growth of a p-type semiconductor, Cu2O on Au nanocrystals (NCs)...

We present temperature-dependent (from room temperature to 80 °C) absorption spectra of Au/SiO2 core-shell nanoparticles (NPs) (core diameter: ∼25 nm) in water in the range from 1.5 to 4.5 eV, which spans the localized surface plasmon resonance (LSPR) and the interband transitions. A decrease in absorption with temperature over the entire spectral...

Light‐driven nanomotors have attracted much attention due to their potential applications. The movement of conventional nanomotors typically occurs in the solution phase, which limits their application fields. Utilizing visible light to drive nanomotors at the solid–liquid interface represents a grand challenge due to the large friction force betwe...

Light‐driven nanomotors have attracted much attention due to their potential applications. The movement of conventional nanomotors typically occurs in the solution phase, which limits their application fields. Utilizing visible light to drive nanomotors at the solid–liquid interface represents a grand challenge due to the large friction force betwe...

Symmetry‐breaking synthesis of colloidal nanocrystals with desired structures and properties has aroused widespread interest in various fields, but the lack of robust synthetic protocols and the complex growth kinetics limit their practical applications. Herein, a general strategy is developed to synthesize the Au–Cu Janus nanocrystals (JNCs) throu...

Plasmonic metal nanostructures generate vivid colors with high spatial resolution. Active control of plasmonic pixels by electrical means, which is compatible with integrated circuit technologies, is a promising technique for dynamic full color reflective display. However, the development of electrical plasmonic display is still limited by the diff...

Conductive polymers are attracting much attention for realizing active plasmonics on conventional static plasmonic nanostructures because of their variable dielectric functions. Combining organic conductive polymers with inorganic plasmonic nanostructures allows for the creation of active devices, such as active metasurfaces, reconfigurable metalen...

Resolving the dynamics of photo-excited d-holes in metallic nanostructures is one step in the rational design of plasmonic photocatalysis. Here, we track the creation and emission of charge carriers in catalytically important plasmonic copper nanocubes using single particle spectroscopy. We show that interband transitions dominate the absorption an...