Research On Bionic Structure Color Based On Different Microstructure

Some creatures in nature exhibit rich color,which is derived from pigments and partly from physical color.The colors that produced by pigments or dyes usually deteriorate or degrade,and the dyeing process is easily to cause environmental pollution.Physical coloring is the optical effect of light on the microscopic scale,such as interference,refraction,diffraction,etc.It is potential to be used as an effective substitution for chemical dyeing to avoid the drawbacks.Physical color produced by optical effects is called structural color.Structural color research has been widely carried out in textile,sensing,anti-counterfeiting and other fields.Some special properties can be obtained by mimicking the microscopic nanostructures that produce structural colors in nature,such as the artificially synthesized structural colors.Therefore,bionics structural color produced by different microstructures is of great significance.In this thesis,structural colors are prepared by imitating microstructures of microscopic thin films,microscopic colunnar materials,and microscopic nanospheres in nature.The contents are as follows:(1)Nanofilms are prepared on the surface of three-dimensional(3D)printed objects in order to solve the difficulty of surface coloring on 3D printed samples.The results show that titanium dioxide(TiO2)films with structural colors can be obtained by atomic layer deposition(ALD)on silicon wafers and 3D printed substrates.Films with different thicknesses can be obtained by adjusting cycle numbers,and different colors are regulated by adjusting thickness.TiO2 film deposited on the 3D printed objects has non-iridescent effect due to the rough surface,and objects can be conformally coated.This technique verifies the feasibility of coloring on complex surfaces by ALD deposition.(2)Directly prepare structural color fiber membranes in one step by preparation of aligned fibers similar to the microscopic columnar materials in nature.The aligned nanofibers can be prepared by new designed parallel-electrode collecter,and the fibers have good orientation and large area.The electrospun fiber film obtained from aligned fibers can exhibit structural color.Aligned fibers are affected by changing electrospinning process and solution composition,and the structural color is related to the diameter of the fibers and the aggregation of the fiber membranes.(3)Fe3O4 nanoparticles are prepared by imitating assembly of microscopic nanospheres in nature,and reversible magnetically responsive photonic crystals are prepared by rapid assembly of external magnetic fields.The study found various factors in the synthesizing process of microspheres affect the microspheres size,such as the type and content of the precursor iron source,the content of poly(4-styrenesulfonic acid-co-maleic acid)sodium salt(PSSMA),and sodium acetate(NaAC).At the same time,the change of the magnetic field strength causes color transformation,and the change is fast and reversible.This method is of great significance for the preparation of fast reversible responsive structural photonic crystals.