%0 DATA
%A Md. Anamul, Haque
%A Kei, Mito
%A Takayuki, Kurokawa
%A Tasuku, Nakajima
%A Takayuki, Nonoyama
%A Muhammad, Ilyas
%A Jian Ping, Gong
%D 2018
%T Tough and Variable-Band-Gap Photonic Hydrogel Displaying
Programmable Angle-Dependent Colors
%U https://acs.figshare.com/articles/Tough_and_Variable-Band-Gap_Photonic_Hydrogel_Displaying_Programmable_Angle-Dependent_Colors/5756340
%R 10.1021/acsomega.7b01443.s001
%2 https://ndownloader.figshare.com/files/10140657
%K angle-dependent colors
%K photonic gel sheet exhibits
%K tunable photonic
%K PAAm layer thickness
%K bulk geometry
%K gel sheet
%K rocking curves
%K sensor technologies
%K Variable-Band-Gap Photonic Hydrogel
%K Programmable Angle-Dependent Colors One-dimensional photonic crystals
%K light illumination angles
%K angle dependence
%K sheet geometry
%K angle-independent color
%K photonic band gaps
%K sheet surface
%K light modulation
%K angle-dependent behavior
%K photonic hydrogels
%K ductile polyacrylamide
%K photonic materials
%K index variation
%K lamellar bilayer
%K gel rod exhibits
%K band gaps
%K bulk geometries
%X 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 Braggâ€™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.