Bionic Design And Manufacturing Technology Of Sensing With Optical Response Structure Inspired By Butterfly

As evident from the ongoing COVID-19 pandemic,the rapid and accurate non-contact detection of body temperature and viruses is crucial for the effective prevention of disease spread.Sensor,as the most critical component in the detection process,is becoming extremely critical and important.Sensor can easily detect the measured information and transform them into electrical signals or other required forms according to certain rules.So,it can always meet the requirements of information transmission,processing,storage,display,recording,and control.The optical sensor is a type of sensor that converts the external stimulus signal into an optical signal output.With the development of technology,the application of optical sensors is constantly expanding.In industry,to improve work efficiency and production quality,optical sensors can be used to measure,track and monitor various parameters.In the medical field,optical sensors can be used to detect the internal state of the human body,as well as to detect and monitor the function of the cardiovascular system.In the military field,optical sensors can be used to detect and monitor potential threats so that counter-measures can be taken quickly and effectively.Furthermore,optical sensors can also be used to improve the safety of autonomous driving,thus reducing the number of road accidents.In fact,the design of sensing materials is the cornerstone for sensors,referring to materials structures,materials composition,optimization methods,and packaging techniques.Driven by the increasing demand for chemistry,biology,and virus monitoring,some innovative sensors are emerging in endlessly.While they have many advantages,such as high sensitivity and fast response time,they also have some limitations.For example,some optical sensors have poor sensing material stability and are prone to degradation over time,which may affect their performance and accuracy.Some optical sensors can only detect one type of external signal.Even if multi-parameter detection is realized,the selectivity in multi-parameter detection is limited and may not have high selectivity for specific analytes.Some optical sensing materials may not have a high degree of reproducibility from batch to batch,which can have an impact on their reliability.In addition,it is still difficult to optimize the design of sensor materials due to the complex interaction between the function,structure,composition,preparation methods of sensor materials and its actual service conditions.Over millions of years of evolution,some creatures in nature are absolutely "top masters" in the synthesis and application of optical materials.They can always regulate the micro-/nanostructures on its body surfaces to improve some optical properties of materials.Thanks to the dazzling optical properties,butterfly wings become the typical representative of the optical bionics.Inspired by the optical response structure of butterfly wing scales in nature,three kinds of butterflies with typical functional optical response structure were selected as research objects in this paper,including the Morpho,Pieris rapae and Talbotia naganum.Firstly,the macroscopic morphology,microscopic morphology and composition of the individual were observed and characterized in detail.It was found that the surface of the Morpho butterfly wings has bright structural color and shows a reversible specific optical response to the organic solvent.The surface of the wings of Pieris rapae and Talbotia naganum has a strong scattering characteristic for incident light,and the reflectance of butterfly wings is as high as 70 %-90 % for vertically incident light.Due to the "roughness amplification effect",the surface of the three butterfly wings showed hydrophobicity and superhydrophobicity.Then,the characteristic size parameters of the optical response characteristic structure of each butterfly wing were obtained.According to the bionic thinking from "likeness in form" to "likeness in spirit",combined with the decisive factors affecting the optical response characteristic structure,the bionic visual model of butterfly wing’s optical response characteristic structure was respectively established.Through analysis,it is found that the position of the reflection peak on the surface of the light response structure is determined by the thickness and distribution form of the lamellae structure and whether ridge structure is introduced,and the reflectivity is determined by the number and width of the lamellae structure.Inspired by the optical response structure of butterfly wing scales,a design method for optical response sensing materials is proposed.Finally,three kinds of bioinspired optical response sensing materials and components were designed and prepared for temperature response and temperature and p H dual stimulus response.In terms of temperature response,a bioinspired temperature responsive microgel has been prepared and its application in smart windows is explored.Through the characterization of the microgels,it was found that the temperature responsive microgels exhibited nanoscale spherical structures of different sizes on the micro scale,transparent on the macro scale,and had significant thermochromic characteristics.The microgel bioinspired smart window has high visible and infrared transmittance at low temperature,and retains good visible transmittance and considerable infrared modulation rate after heating.Due to the low transmission of infrared light as the temperature rises,the bioinspired smart window has good temperature control properties on the surface of objects and in confined spaces.Aiming at the dual-response of temperature and p H,a bioinpsired dual-responsive sensing material was prepared using the natural photonic crystal structure as a prototype.It is found that the bioinspired dual-responsive sensing material has perfectly inherited the fine photonic crystal structure on the surface of the natural butterfly wing.Its optical response to temperature,p H and cyclic reversibility were tested.It is found that bioinspired dual-responsive sensing materials can make optical response to temperature and p H stimuli,and because of reversible phase transition of the stimulus responsive materials,bioinspired dual-responsive sensing materials show reversible optical response characteristics to p H and temperature stimuli.Then,to overcome the limitation of the above dual-response sensing materials,which is limited by the size of the natural butterfly wing,a bioinspired dual-responsive sensing element inspired by the optical response structure of the butterfly wing was designed and prepared.The surface morphology of the sensor was characterized,and it was found that the surface of the sensor is uniform,and the adhesion between the two layers is good,and the structure color is bright in the macro.The p H and temperature response characteristics of the bioinspired dual-response sensor were tested.It was found that the surface of the bioinspired dual-response sensor can change color with the changes in external stimuli.The repeatability of the bioinspired dualresponse sensor is verified.The results show that the bioinspired dual-response sensor has good repeatability.In summary,in this paper,typical butterfly species in nature are taken as biological prototypes,and the factors affecting their optical response sensing characteristics such as the morphology of their optical response surface,the characteristic structure of their cross-scale classification and material composition are systematically studied by using bionic thinking.Combined with the decisive factors affecting the characteristic structure of the optical response,the bionic visual model of the optical response structure of the butterfly wing was established respectively,and the corresponding bioinspired optical responsive sensing functional materials were prepared and characterized.In addition,the theoretical model and numerical simulation are used to reveal the internal relationship between the characteristic structure of the typical butterfly wing and its excellent optical response sensing function.This study provides certain data reference and theoretical basis for the design and development of novel bionic optical response sensing functional materials.