Preparation And Application Of High Optical Performance Structure Color Materials

The structural color has the characteristics of never fading,intelligence（stimulus response,color adjustable）and environmental friendliness.Due to its special light control performance,it has broad application prospects in the fields of optical devices,chemical and biochemical sensors,and full-color displays.The structural color is produced by the mutual interference of the microstructure of matter and light.Structural color materials have long-range ordered or short-range ordered long-range disordered internal structures,which exhibit different characteristics due to their internal structures.In this paper,high-brightness non-i-colored structural color films prepared by short-range ordered long-range disordered amorphous photonic structures are introduced.The crack-freeα-Fe₂O₃ inverse opal structural color materials are prepared by sacrificial template method.The main contents of this paper include:1.Highly Brilliant Noniridescent Structural Colors Enabled by Graphene Nanosheets Containing Graphene Quantum DotsThe most important properties of noniridescent structural colors of amor-phous photonic structures（APS）are sufficient color brightness and saturation,which are difficult to be optimized simultaneously.Herein,highly saturated and brilliant noniridescent structural colors are achieved by introducing graphene nanosheets,which contain a fraction of graphene quantum dots（GQDs）,into the short-range ordered APS.The effective modulation of the photoluminescence（PL）of GQDs by the selective enhancement of absorption at the blue pseudo photonic bandgap edges of the APS boosts the PL with wavelength matching that of the photonic bandgap and thus enables high structural color brightness;the uniform light absorption of graphene nanosheets in the whole visible spectra contributes to the high color saturation.Furthermore,by using APS films with short-range order as templates,a brilliant colorful humidity sensor is demonstrated.Compared with the conventional sensing platform based on photonic crystals,the humidity sensor with brilliant noniridescent structural colors is more convenient by avoiding the confusing color dependence on the viewing angles.The improvement in the structural color brightness of the APS films by facile graphene doping will facilitate their practical applications in fields of decorations,packaging,pigments,sensors,displays,or other color-related areas.2.Elimination of cracks inα-Fe₂O₃ inverse opal structure photoanode by suture ofγ-FeOOH nanowiresThe inverse opal structure material can be applied to various aspects such as optical,electronic and（bio）chemistry.However,the generation of uncontrollable cracks in the process of preparing the inverse opal structure seriously affects the integrity and optical properties of the film.In the experiment,the crack-freeα-Fe₂O₃ inverse opal structure photonic crystal photoanode was successfully prepared by using the"sacrificial template method".By adjusting the particle size of the colloidal particles in the template,the photonic band gap can be obtained to cover the entire visible light band,and the color is uniform and beautiful.In the experiment,the FeCl₃ precursor solution was filled between the crack of the template and the latex particles.In the constant temperature and humidity environment,FeCl₃ was hydrolyzed to form acicularγ-FeOOH.During the high temperature calcination,the acicularγ-FeOOH would dehydrate and condense into sphericalα-Fe₂O₃,due to the action of the condensation force,the nano-sized needle-likeγ-FeOOH slowly"stitched"the crack to obtain a crack-free inverse opal structure having a spherical structure ofα-Fe₂O₃.The elimination of cracks significantly improves the optical properties and electron transport efficiency of the film.Under the optimal photonic band gap condition,The crack-free inverse opal structure photoanode is more than twice as efficient as the photo-decomposed water compared to the cracked inverse opal structure.