Study About Multifunctional Wearable Sensor Based On Patterned Graphene Fabric Array

Flexible wearable electronic sensors have attracted wide attention in recent years due to their advantages of light structure,portability,excellent electrical performance and easy integration.It has a broad application prospect in human health monitoring,electronic skin devices,human motion detection,implantable medical devices and other fields,especially in the field of individualized health care and disease early diagnosis which have became a current research hot spot.Various flexible wearable sensors have been widely developed for human health monitoring.It is difficult for a single detection data to accurately distinguish the health status of an individual,so integration and multifunction are important trends in the development of wearable sensors.The first problem needed to be solved is how to realize the integration of sensor materials.As a carbon material with good mechanical properties,high thermal conductivity and carrier mobility,graphene is an ideal sensor material for the preparation of flexible electronic devices.With the rapid development of graphene on a large scale,making patterned graphene becomes more and more important in the application of flexible sensing devices.Currently,the common methods of patterning graphene materials are lithography and inkjet printing,but these methods are not suitable for mass production.Therefore,this paper proposes a method for the preparation of patterned graphene arrays using different wettability on hydrophilic/hydrophobic surfaces,and constructs a multifunctional wearable sensor using graphene array design.At the same time,graphene composite gel was prepared and combined with graphene array to further construct a multifunctional wearable sensor for wound care.The research contents in this paper are as follows:1.A new method for the preparation of patterned graphene arrays was proposed,which was to rapidly prepare graphene oxide(GO)arrays using GO solutions with different wettability on the surface of a hydrophilic/hydrophobic flexible substrate.As a flexible substrate material,medical gauze was treated as a hydrophobic surface by vinyl trichlorosilane,and a mask with a pattern was attached to the hydrophobic gauze for plasma surface treatment,so that the parts that need to be patterned had hydrophilic properties.The GO solution was infiltrated into the hydrophilic surface of the gauze to form a patterned GO array.By chemical reduction of GO arrays,reduced graphene oxide(rGO)arrays can be prepared simply,quickly and at low cost.2.The GO/rGO array was used to construct a multifunctional wearable sensor for simultaneously monitor temperature/humidity/pressure.The sensor was divided into three sensing layers: the upper GO array was used for humidity detection,the middle layer Ecoflex film was sandwiched between two rGO arrays to form a capacitive sensing layer for pressure detection,and the bottom rGO array was used for human body temperature detection.Laminated method was used to construct multifunctional wearable sensor in which each layer sensor array for each pixel in a laminated joint.The response performance of each sensor layer and the interaction between the detection signals were discussed in detail.It can simultaneously monitor the external temperature,humidity,inductive touch and human joint movement,and directly reflect the spatial distribution of temperature/humidity/pressure.3.Graphene composite gels were prepared and sensitivity to pH and antimicrobial activity were studied.A multifunctional wearable sensor for pH monitoring and drug release for wound care was constructed using a patterned graphene array and graphene composite gels.The sensor was divided into two sensing units: the graphene composite gel as a drug delivery system for drug delivery,and the rGO array for pH detection.The two sensor units were arranged side by side to construct a multifunctional wearable sensor on the medical adhesive tape,so as to realize the function of real-time pH monitoring at the wound and drug delivery on demand within the pH range of wound.