Tough and Variable-Band-Gap Photonic Hydrogel Displaying
Programmable Angle-Dependent Colors
Md. Anamul Haque
Kei Mito
Takayuki Kurokawa
Tasuku Nakajima
Takayuki Nonoyama
Muhammad Ilyas
Jian Ping Gong
10.1021/acsomega.7b01443.s003
https://acs.figshare.com/articles/media/Tough_and_Variable-Band-Gap_Photonic_Hydrogel_Displaying_Programmable_Angle-Dependent_Colors/5756334
One-dimensional photonic crystals
or multilayer films produce colors
that change depending on viewing and light illumination angles because
of the periodic refractive index variation in alternating layers that
satisfy Bragg’s law. Recently, we have developed multilayered
photonic hydrogels of two distinct bulk geometries that possess an
alternating structure of a rigid polymeric lamellar bilayer and a
ductile polyacrylamide (PAAm) matrix. In this paper, we focus on fabrication
of composite gels with variable photonic band gaps by controlling
the PAAm layer thickness. We report programmable angle-dependent and
angle-independent structural colors produced by composite hydrogels,
which is achieved by varying bulk and internal geometries. In the
sheet geometry, where the lamellae are aligned parallel to the sheet
surface, the photonic gel sheet exhibits strong angle-dependent colors.
On the other hand, when lamellae are coaxially aligned in a cylindrical
geometry, the gel rod exhibits an angle-independent color, in sharp
contrast with the gel sheet. Rocking curves have been constructed
to justify the diverse angle-dependent behavior of various geometries.
Despite varying the bulk geometry, the tunable photonic gels exhibit
strong mechanical performances and toughness. The distinct angle dependence
of these tough photonic materials with variable band gaps could benefit
light modulation in displays and sensor technologies.
2018-01-04 00:00:00
angle-dependent colors
photonic gel sheet exhibits
tunable photonic
PAAm layer thickness
bulk geometry
gel sheet
rocking curves
sensor technologies
Variable-Band-Gap Photonic Hydrogel
Programmable Angle-Dependent Colors One-dimensional photonic crystals
light illumination angles
angle dependence
sheet geometry
angle-independent color
photonic band gaps
sheet surface
light modulation
angle-dependent behavior
photonic hydrogels
ductile polyacrylamide
photonic materials
index variation
lamellar bilayer
gel rod exhibits
band gaps
bulk geometries