Electrodeposition of Large Area, Angle-Insensitive Multilayered Structural Colors

Abstract

We demonstrate structural colors produced by a simple, inexpensive, and nontoxic electrodeposition process. Asymmetric metal–dielectric–metal (MDM) multilayered structures were achieved by sequential electrodeposition of smooth gold, thin cuprous oxide, and finally thin gold on conductive substrates, forming an effective optical cavity with angle-insensitive characteristics. Different colors of high brightness were achieved by simply tuning the thickness of the electrodeposited middle cavity layer. This process is compatible with highly nonplanar substrates of arbitrary shape, size, and roughness. This work is the first demonstration of solution-processed, electrodeposited, MDM film stacks that are uniform over large areas and highlights the clear advantages of this approach over traditional deposition or assembly methods for preparing colored films.

Nanophotonic Structural Colors

“…Saturated and vivid colors can also be achieved by employing a Fabry–Pérot (FP) cavity, as shown in Figure g. − A Fabry–Pérot configuration is an optical cavity based on an interferometer or etalon that consists of two parallel reflective surfaces, first described and demonstrated by Fabry and Pérot back in 1899 . An FP cavity in its simplest design consists of a backreflector (made of metal or dielectric stack), and a dielectric with an optical thickness commensurate with multiples of half wavelengths of visible light in the cavity.…”

Thin‐Metal‐Film‐Based Transparent Conductors: Material Preparation, Optical Design, and Device Applications

“…Thin metal films are also essential components in one representative category of transmissive optical spectrum filters that is based on the metal–dielectric–metal (MDM) Fabry–Pérot cavity configuration. [ 277–283 ] The schematic drawing of a MDM‐based filter consisting of a dielectric layer (SiO 2 ) sandwiched by two thin metallic films (Ag) is shown in Figure a, and the cross‐sectional SEM image of a representative device is shown in Figure 25b. [ 278 ] The thicknesses of the two Ag layers are fixed at 25 nm, and that of the SiO 2 layer varies to adjust the transmission spectrum through the DMD filter.…”

Self‐Assembled Plasmonic Coaxial Nanocavities for High‐Definition Broad‐Angle Coloring in Reflection and Transmission

“…[ 3b,7 ] The introduction of a back‐reflector below the nanoparticles helps to increase the scattering efficiency in reflection sacrificing coloring in the transmitted light. In this geometry, various nanocavity‐based plasmonic antennas, such as nanodisks on a film, [ 1a,3b ] MIM nanocavities with varied insulator gaps, [ 8 ] nanorod and nanotrench structures [ 9 ] have been demonstrated with an ultimately small pixel size leading to image resolution more than 100 000 DPI, a broad and bright color gamut together with high tolerance to the viewing angle. [ 10 ] Utilizing the combined action of specular and diffused reflections, the capabilities of nanostructured plasmonic surfaces were further extended to introduce 3D effects.…”