Fabrication And External Fields Control Of Real Time Responsive Photonic Crystal Microsphere Array

Photonic crystal consisting of two or more materials with different dielectric constant and ordered arrangement can restrict propagation of photons within a certain range of wavelength,and shows vivid structural colors.Stimuli-responsive photonic crystal can change their structural colors in the varing external field such as temperature,electric or magnetic field,pH,solvents or medicines.Photonic crystal responding to environmental changes have been studied widely in many fields,for example,the photonic microchips,colorimetric sensors,display materials,bio-inspired devices,and biomedical applications.The multi-responsive photonic devices can be desired via different stimuli-responsive material combining with opal or inverse-opal photonic crystals,thus realizing the detection to the external stimulus and giving rise to extensive attentions in many fields.However,the researches focus on planar photonic crystals and pay fewer attention to stereo-three dimention and flexible photonic crystals with multiple environmental real-time responses.Therefore,we fabricated multi-responsive materials combining with opal and inverse opal photonic crystals based on structural design.The main researches are as follows:1.Specific responsive inverse opal structure photonic crystal microsphere was desingned and fabricated based on the molecular imprinted hydrogel.Monodispersed SiO2 nanoparticles were fabricated via modified STOBER method,the opal microsphere templates were obtained via microfluidic chips.Combining with molecular-imprinted hydrogel with the UV light solidification in low temperature environment,we obtain the complete inverse opal molecular imprinted hydrogel microspheres after removing the opal SiO2 microsphere template.The osmotic pressure of the microsphere increased with the existence of the imprinted molecule,resulting in the lattice distance change of the inverse opal microsphere,and the photonic bandgap can reversibly red shift.Meanwhile,we systematically studied the size effect of the inverse opal imprinted molecular hydrogel spheres,the detection limitation and range can be adjust via changing the size of the spheres.We proposed a new strategy to fabricate the portable specifically colorimetric detection,and we realized the fast and convenient detection to the MPA molecules.2.We fabricated magnetic responsive Janus structrural colored beads(JSCBs)via one-step method.Introducing PDMS into the self-assembly system,we finished the self-assembly of colloidal nanoparticles,the deposition of the magnetic nanoparticles and the solidification of PDMS simultaneously.The JSCBs possessed long range ordered face-centered cubic arrangement,the structural color of the photonic crystal face JSCBs was vivid.Because of the large difference of the magnetic nanoparticles content,the JSCBs was sensitive to the changing magnetic field,and the JCSBs could keep their direction synchronously with the varing magnet.Meanwhile,we proposed a kind of display devices which could respond to the varing magnetic direction via combining the multicolored JSCBs with reeded template.The multiclolored JSCBs array can realize information encoding,images expressing and concealing,which have the promising application in real-time magnetic display,information recording.3.We designed and fast fabricated large scale,controllable shape opal thermo-sensitive structural colored(TSSC)films via roller coating method.The resulting TSSC films possessed obvious structural color in the room temperature.With the environmental temperature increasing,the color of the TSSC films reversibly transferred from reflection state to transparent state,and the reflection peak intensity of the TSSC films was decreased obviously.The flexibility and mechanism of the TSSC films were remarkably enhanced according to add appropriate deionized water into the precursor of the TSSC film.We proposed the flexible NIR real-time responsive photonic crystal anti-counterfeiting labels and multicolored TSSC display membranes.The color of the TSSC films can transferred from reflection state to transparent state,and we can obtain the concealing binary code and the non-contacting information via 980 nm NIR laser.With the removing of the NIR laser,the multi-colored TSSC films can reversibly recover the reflection state.The flexible TSSC films exploited the new strategy in non-contacting information recording on the photonic crystal membranes.