Research On Flexible Temperature Sensor Of Graphene And Titanium Dioxide Based On Non-Woven Fabric

Recent years,with the development of wearable smart devices,wearable and flexible temperature sensors have attracted much attention.In this work,we selected graphene and titanium dioxide as temperature sensitive materials and fabricated wearable and flexible temperature sensors based on calcium alginate nonwoven fabric and cellulose nonwoven fabric by dipping mathod.Its comprehensive performance and application were characterized as well.First of all,graphene was selected as temperature sensing material and titanium dioxide as reinforced temperature sensing material,calcium alginate fibers and cellulose fibers with advantages of flexible,comfort and safety were selected as the substrate of the sensor.Randomly arranged fibers formed into nonwoven fabric,which can eliminate the directivity of the temperature sensor and is considered as an ideal matrix structure of the temperature sensor.Also,sodium alginate and microcrystalline cellulose were selected as dispersants of graphene and fixing agent,whose composition were the same as the substrate.Blended the graphene dispersants with titanium dioxide into uniform and stable dispersion,and coated it directly onto a flexible non-woven fabric substrate by using a simple dip-coating method to obtain the flexible temperature sensor.Finally,we analysed and discussed the performance and applications of the temperature sensors,it shows that the temperature based on both calcium alginate and cellulose behaved as negative temperature coefficient feature in a certain range of temperatures and exhibited excellent sensing performance of good linearity?the nonlinear errors are 5.54%and 4.84%,respectively?,good sensitivity(TCRs are-1.5^oC^-11 and-0.9^oC^-1,respectively),high accuracy of 0.1 ^oC,high repeatability?repetitive deviations are 4.02%and 3.47%,respectively?and relatively low hysteresis?hysteresis were 14.2%and 6.38%respectively?,as well as good stability and less response time.At the same time,to better simulate the actual application,we analyzed and excluded the factors affecting the temperature sensing such as humidity and strain,and tried to realize the warning of temperature change by combining itwith other thermochromic materials.