Thermal Responsive Photonic Crystal Achieved through the Control of Light Path Guided by Phase Transition

Abstract

Responsive photonic crystal is widely considered in the field of anti‐counterfeiting and information encryption because of their structural color changes caused by external stimulation. However, the response signal is usually achieved by adjusting the periodic lattice constant based on Bragg's law with volume changes. Thus, it is a great challenge to achieve the response of photonic crystals by non‐array parameter control. Herein, novel thermal responsive photonic crystal (TRPC) with low angle dependent structural color is fabricated by introducing poly(ethylene glycol) into the structure of low angle dependent SnO2 inverse opal. The response is achieved through the control of light path guided by phase transition and the significant volume change caused by the change of traditional array parameters can be effectively avoided. Meanwhile, the low angle dependent structural color of TRPC can effectively reduce the interference of observation angle change to response signal caused by external thermal stimulation. Patterned responsive photonic crystals with temperature gradient response are easily obtained by combining confinement self‐assembly and direct template method, and the patterns can be presented and hidden by the control of light path, showing great potential in anti‐counterfeiting and information encryption fields.

Photoinduced Superhydrophilic TiO2–PHEA/PS Photonic Crystal Composites with Vivid Structural Color, Self‐Cleaning Ability, and Robust Structure

“…The relationship between the reflection peak position and the diameter of microspheres is consistent with the Bragg equation (Table S1, Supporting Information). [33] The reflection peak positions of TiO 2 -PHEA/PS PC composites were 476, 534, and 630 nm, and the corresponding peak intensities were 23%, 33%, and 27%, respectively (Figure 1d). Compared with PS PCs, the redshift of the peak position was 3, 1, and 3 nm, and the decrease of peak intensity was 13%, 12%, and 9%, respectively.…”

Rapid Fabrication of Alcohol Responsive Photonic Prints with Changeable Color Contrasts for Anti‐Counterfeiting Application

“…Photonic crystals (PCs) have shown wide applications in color displays, [ 1–6 ] pigments, [ 7,8 ] printings, [ 9–15 ] sensing, [ 16–31 ] anti‐counterfeiting, [ 32–44 ] optical devices, [ 45–48 ] and photocatalysis. [ 49–51 ] Among these, the photonic patterns have attracted considerable interests owing to its potential in integration of low‐cost fabrication, long‐term usability, anti‐photobleaching, and anti‐counterfeiting.…”

Controllable Radical Polymerization of Selenide Functionalized Vinyl Monomers and Its Application in Redox Responsive Photonic Crystals

“…used SnO 2 inverse opal PCs, achieving the control of light path guided by phase transition instead of change of traditional thermally induced lattice parameter. [ 34 ] However, it seems to have been poorly reported based on redox‐triggered opals and inverse opals, [ 35,36 ] especially the SiO 2 templated studies with redox or electrochemical response, [ 37,38 ] which is also important in this field. In 2009, Ozin and co‐workers designed the first example of an electroactive inverse opal, achieving all colors at low voltages.…”