The microstructure, wettability and chemical composition of the butterfly wing surfaces were investigated by a scanning electron microscope, a contact angle meter and a Fourier transform infrared spectrometer. The mic...The microstructure, wettability and chemical composition of the butterfly wing surfaces were investigated by a scanning electron microscope, a contact angle meter and a Fourier transform infrared spectrometer. The micro/nano structural models for hydrophobicity of the butterfly wing surfaces were established on the basis of the Cassie equation. The hydrophobicity mechanisms were discussed from the perspective of biological coupling. The butterfly wing surfaces are composed of naturally hydrophobic material and possess micro/nano hierarchical structures, including primary structure （micrometric scales）, secondary structure （nano longitudinal ridges and lateral bridges） and tertiary structure （nano stripes）. The wing surfaces exhibit high hydrophobicity （contact angle 138°-157°） and low adhesion （sliding angle 1°-3°）. The micromorphology and self-cleaning performance of the wing surfaces demonstrate remarkable anisotropism. The special complex wettability ascribes to a coupling effect of the material element and the structure element. In microdimension, the smaller the width and the bigger the spacing of the scale, the stronger the hydrophobicity of the wing surfaces. In nano-dimension, the smaller the height and the smaller the width and the bigger the spacing of the longitudinal ridge, the stronger the hydrophobicity of the wing surfaces. This work promotes our understanding of the hydrophobicity mechanism of bio-surfaces and may bring inspiration for biomimetic design and preparation of smart interfacial materials.展开更多
The Morpho butterfly is famous for its typical structural color and has increasingly attracted the interest of scholars in a wide variety of research fields. Herein, it was found that the color of Morpho menelaus butt...The Morpho butterfly is famous for its typical structural color and has increasingly attracted the interest of scholars in a wide variety of research fields. Herein, it was found that the color of Morpho menelaus butterfly wings is not only structure-based but also viewing-angle-dependent. Firstly, the discoloration effect of this typical butterfly was confirmed by a series of experiments. Then, the general form, arrangements, and geometrical dimensions of the scales were observed using a stereomicroscope. Scanning electron microscopy was also used to examine the two-dimensional morphologies and structures of a single scale. Afterwards, one model with the optimized three-dimensional profile of the structure was described using Pro-engineer software. The associate model was then analyzed to reconstruct the process between the incident light and the model surface. Finally, the mechanism of the angle-dependent discoloration effect was analyzed by theoretical calculation and optical simulation. Different light propagation paths and the length of the incident light at different angles caused destructive or constructive interference between the light reflected from the different layers. The different spectra of the reflected light make the wings appear with different structural colors, thereby endowing the angle-dependent discoloration effect. The consistency of the calculation and simulation results confirms that these structures possess an excellent angle-dependent discoloration effect. This functional "biomimetic structure" would not only be of great scientific interest but could also have a great impact in a wide range of applications such as reflective displays, credit card security, and military stealth technology.展开更多
SiO2 and ZnO inverse structure replicas have been synthesized using butterfly wings as templates. The laser diffraction performance of the SiO2 inverse structure replica was investigated and it was found that the zero...SiO2 and ZnO inverse structure replicas have been synthesized using butterfly wings as templates. The laser diffraction performance of the SiO2 inverse structure replica was investigated and it was found that the zero-order light spot split into a matrix pattern when the distance between the screen and the sample was increased. This unique diffraction phenomenon is closely related to the structure of the SiO2 inverse structure replica. On the other hand, by analyzing the photoluminescence spectrum of the ZnO replica, optical anisotropy in the ultraviolet band was demonstrated for this material.展开更多
基金supported by the National Natural Science Foundation of China(50875108)the Natural Science Foundation of Jilin Province,China(201115162)the Open Fundof Key Laboratory of Bionic Engineering of Ministry of Education,Jilin University(K201004)
文摘The microstructure, wettability and chemical composition of the butterfly wing surfaces were investigated by a scanning electron microscope, a contact angle meter and a Fourier transform infrared spectrometer. The micro/nano structural models for hydrophobicity of the butterfly wing surfaces were established on the basis of the Cassie equation. The hydrophobicity mechanisms were discussed from the perspective of biological coupling. The butterfly wing surfaces are composed of naturally hydrophobic material and possess micro/nano hierarchical structures, including primary structure （micrometric scales）, secondary structure （nano longitudinal ridges and lateral bridges） and tertiary structure （nano stripes）. The wing surfaces exhibit high hydrophobicity （contact angle 138°-157°） and low adhesion （sliding angle 1°-3°）. The micromorphology and self-cleaning performance of the wing surfaces demonstrate remarkable anisotropism. The special complex wettability ascribes to a coupling effect of the material element and the structure element. In microdimension, the smaller the width and the bigger the spacing of the scale, the stronger the hydrophobicity of the wing surfaces. In nano-dimension, the smaller the height and the smaller the width and the bigger the spacing of the longitudinal ridge, the stronger the hydrophobicity of the wing surfaces. This work promotes our understanding of the hydrophobicity mechanism of bio-surfaces and may bring inspiration for biomimetic design and preparation of smart interfacial materials.
基金supported by the National Natural Science Foundation of China(Grant Nos.51325501,51505183&51290292)China Postdoctoral Science Foundation Funded Project(Project No.2015 M571360)
文摘The Morpho butterfly is famous for its typical structural color and has increasingly attracted the interest of scholars in a wide variety of research fields. Herein, it was found that the color of Morpho menelaus butterfly wings is not only structure-based but also viewing-angle-dependent. Firstly, the discoloration effect of this typical butterfly was confirmed by a series of experiments. Then, the general form, arrangements, and geometrical dimensions of the scales were observed using a stereomicroscope. Scanning electron microscopy was also used to examine the two-dimensional morphologies and structures of a single scale. Afterwards, one model with the optimized three-dimensional profile of the structure was described using Pro-engineer software. The associate model was then analyzed to reconstruct the process between the incident light and the model surface. Finally, the mechanism of the angle-dependent discoloration effect was analyzed by theoretical calculation and optical simulation. Different light propagation paths and the length of the incident light at different angles caused destructive or constructive interference between the light reflected from the different layers. The different spectra of the reflected light make the wings appear with different structural colors, thereby endowing the angle-dependent discoloration effect. The consistency of the calculation and simulation results confirms that these structures possess an excellent angle-dependent discoloration effect. This functional "biomimetic structure" would not only be of great scientific interest but could also have a great impact in a wide range of applications such as reflective displays, credit card security, and military stealth technology.
基金Acknowledgements The authors acknowledge the financial support from the National Natural Science Foundation （NSF） of China （Grant Nos. 60976014, 60976004, and 11074075）, and the Key Basic Research Project of the Scientific and Technology Committee of Shanghai （Grant No. 09DJ1400200）.
文摘SiO2 and ZnO inverse structure replicas have been synthesized using butterfly wings as templates. The laser diffraction performance of the SiO2 inverse structure replica was investigated and it was found that the zero-order light spot split into a matrix pattern when the distance between the screen and the sample was increased. This unique diffraction phenomenon is closely related to the structure of the SiO2 inverse structure replica. On the other hand, by analyzing the photoluminescence spectrum of the ZnO replica, optical anisotropy in the ultraviolet band was demonstrated for this material.
