Production of Structural Colors with High Contrast and Wide Viewing Angles from Assemblies of Polypyrrole Black Coated Polystyrene Nanoparticles.
Structural color with wide viewing angles has enormous potential applications in pigment, ink formulation, displays, and sensors. However, colors obtained from colloidal assemblies with low refractive index contrast or without black additives typically appear pale. Here, we prepare polypyrrole (PPy) black coated polystyrene (PS) nanoparticles and demonstrate well-defined colors with high color contrast and wide viewing angles under ambient light. Depending on the loading of pyrrole during polymerization, PPy nanogranules of different sizes and coverages are grafted to the surface of PS nanoparticles. The bumpy particles can self-assemble into quasi-amorphous arrays, resulting in low angle dependent structure colors under ambient light. The color can be tuned by the size of the PS nanoparticles, and the presence of the PPy black on PS nanoparticles enhances the color contrast by suppressing incoherent and multiple scattering.
Department of Materials Science and Engineering, University of Pennsylvania , 3231 Walnut Street, Philadelphia, 19104, United States.|Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, Suzhou Key Laboratory of Macromolecular Design and Precision Synthesis, College of Chemistry, Chemical Engineering and Materials Science, Soochow University , Suzhou 215123, China.
Xiaoming
X
Yang
Department of Materials Science and Engineering, University of Pennsylvania , 3231 Walnut Street, Philadelphia, 19104, United States.|Institute of Functional Materials, Donghua University , Shanghai 201620, China.
Dengteng
D
Ge
Department of Materials Science and Engineering, University of Pennsylvania , 3231 Walnut Street, Philadelphia, 19104, United States.
Gaoxiang
G
Wu
Department of Materials Science and Engineering, University of Pennsylvania , 3231 Walnut Street, Philadelphia, 19104, United States.
Zhiwei
Z
Liao
Department of Materials Science and Engineering, University of Pennsylvania , 3231 Walnut Street, Philadelphia, 19104, United States.
Shu
S
Yang
high color contrast; nanoparticles; polypyrrole black; structural color; wide viewing angle