Ultralight plasmonic structural color paint

Abstract

All present commercial colors are based on pigments. While such traditional pigment-based colorants offer a commercial platform for large-volume and angle insensitiveness, they are limited by their instability in atmosphere, color fading, and severe environmental toxicity. Commercial exploitation of artificial structural coloration has fallen short due to the lack of design ideas and impractical nanofabrication techniques. Here, we present a self-assembled subwavelength plasmonic cavity that overcomes these challenges while offering a tailorable platform for rendering angle and polarization-independent vivid structural colors. Fabricated through large-scale techniques, we produce stand-alone paints ready to be used on any substrate. The platform offers full coloration with a single layer of pigment, surface density of 0.4 g/m 2 , making it the lightest paint in the world.

Reusable Structural Colored Nanostructure for Powerless Temperature and Humidity Sensing

“…Details on the growth dynamics of the self‐assembly exceed the scope of this paper and can be found in our earlier publications. [ 46,47 ]…”

“…Details on the growth dynamics of the self-assembly exceed the scope of this paper and can be found in our earlier publications. [46,47] Under ambient illumination, the free electrons of the nanoparticles' metal can be coupled to the external light, collectively oscillating in what is termed a localized surface plasmon. While at wavelengths matching the plasmon resonance light is strongly absorbed, off-resonance components are back reflected by the aluminum mirror producing vivid colors.…”

“…Crucially, this ensures that the polymer thickness remains thin enough to maintain the gap-plasmon hybridization and thus vivid coloration that would be lost in far-field interaction between the self-assembly and the cavity. [46,47]…”

“…As discussed previously, the thickness changes of the polymer spacer tune the resonance by shifting the constructive interference condition of the hybrid gapplasmon system. [48] For smaller particles however, the plasmonic resonance is found in the violet/near-UV bands, thus small tuning does not affect as much the overall visible color change, [46,47] whereas for bigger particles the plasmon resonance is found in the center of the visible range, where human eye has a better response, and thus can tell colors apart better. Furthermore, as particle size becomes bigger, the plasmon resonance is shifted to the far-red/IR bands, and less obvious change can be appreciated.…”

Patterning of plasmonic Au nanoparticles on the surfaces of TiOx thin films by solid state thermal dewetting

“…In our work, e-beam evaporator has been used to grow both metal and metal oxide films 27 – 29 TiOx thin films of 100 nm were reactively evaporated at the room temperature with a constant oxygen (O) flow rate using Denton™ e-beam evaporation at a growth rate of 1 Å/s and a deposition pressure of 2E-4 Torr. Metal layers (Au) of 10 nm were also grown on quartz substrates using the same e-beam evaporation, at room temperature, without any oxygen flow.…”