Research On Integration And Human-machine Interaction Of Ti₃C₂T_x Based Sensor

With the rapid development and accelerated integration of big data,Internet of Things and artificial intelligence,the human-machine interaction system has been gradually improved.As people pursue more intelligent and refined information services,human-machine interaction technology also needs to be further improved.Among them,as the window of human-machine interaction,sensor directly determines the quantity and quality of the system to obtain environmental information,and determines the potential of human-machine interaction system.Therefore,it is an important way to promote the development of human-machine interaction application to develop new sensor parts with excellent performance and easy industrialization and integration.With the development of sensor research,a variety of sensor material systems have emerged in recent years.Among them,Ti₃C₂T_x MXene has shown great potential in the field of functional intelligent sensing due to its excellent physical and chemical properties and abundant surface functional groups.However,the pure Ti₃C₂T_x MXene material itself has poor mechanical properties,low sensitivity and insufficient stability,which makes it difficult to be highly integrated,which hinders the application of pure Ti₃C₂T_x MXene material in the field of human-machine interaction to some extent.To solve the above problems,in order to build a stable and efficient human-machine interaction system,this paper selected a new two-dimensional nanomaterial Ti₃C₂T_x MXene as the research object,through composite modification,structural design and other technical means to improve its sensing performance and spatial,functional integration,design and preparation of a series of Ti₃C₂T_x MXene-based sensors.The basic sensing performance and human-machine interaction application are studied systematically.The main research contents are as follows:（1）In order to improve the pressure sensing performance of MXene-based materials,multilayer Ti₃C₂T_x@ZIF-67@N-CNTs composite films were prepared by alternate vacuum filtration.Mix Ti₃C₂T_x MXene solution with ZIF-67@N-CNTs Preparation of Multilayer Composite Thin Films by Alternate Vacuum Suction Filtration of Suspended Liquid.The results of X-ray diffraction analysis and scanning electron microscopy showed that the synthesized materials had excellent crystallinity and obvious hierarchical structure.Based on this,a pressure sensor with a sandwich structure was designed and assembled.Through I-V curve testing,dynamic response testing,sensitivity,response recovery time,and cycle stability testing of the sensor,the results show that the device has a high sensitivity of 9.2 k Pa^-1 and a low pressure detection limit of 0.03 k Pa,while having a response time of 60 ms and a recovery time of 30 ms,and has extremely strong stability in a pressure cycle test of 22000 s.Based on the excellent pressure sensing performance of the device,it has been applied to human limb motion and pulse wave monitoring.The results show that it can stably monitor finger and wrist flexion and pulse response,and it has great application potential in the field of human health monitoring.（2）In order to improve the spatial integration of MXene based material sensors,the Ti₃C₂T_x@PEDOT:PSS composite pressure sensor and its pressure sensing array were studied.The Ti₃C₂T_x and PEDOT:PSS were sprayed layer by layer by solution spraying method.Then the Ti₃C₂T_x@PEDOT:PSS composite pressure sensor and 3×3pressure sensor array were prepared.This flexible pressure sensor has a wide pressure response range of 0.01-50 k Pa,a high sensitivity of 44 k Pa^-1,and a fast response/recovery time of 140 ms/100 ms.It still has good pressure performance stability after 13000 s pressure cycle tests.The pressure sensor has the potential for application to human health monitoring and facial recognition.After that,the homogeneity of the 3×3 pressure sensing array was studied.Tests showed that nine sensors had similar current responses under the same pressure,so the sensing array had good uniformity and stability.It was able to detect the spatial distribution of the pressure received and the bending distribution of the array,laying the foundation for the preparation of large-scale high-performance flexible pressure sensing arrays.（3）In order to improve the functional integration of MXene-based material sensors,a dual-function sensor based on Ti₃C₂T_x/AgNWs/Tissue composite film was studied.Ti₃C₂T_x MXene nanosheets and AgNWs were mixed with Tissue suspension and self-assembled,then the composite thin films of Ti₃C₂T_x/AgNWs/Tissue were filtered by vacuum.The composite thin films were assembled into pressure sensors and humidity sensors through different encapsulation methods.This dual-function flexible sensor exhibits high pressure sensitivity(31.0 k Pa^-1)and humidity sensitivity（3300%）as well as short pressure response/recovery time（63 ms/123 ms）and humidity sensing response/recovery speed（7.3 s/11 s）.It has excellent pressure cycle stability（19000 s）and humidity cycle stability（5000 s）.The MXene-based sensor has successfully realized dual-function sensing integration,it can be applied to human mechanical and humidity signal monitoring.（4）The Ti₃C₂T_x MXene based flexible sensor and circuit system are integrated into sensor integrated systems and applied to human-computer interaction.Ti₃C₂T_x@ZIF-67@N-CNTs pressure sensor,8×8 Ti₃C₂T_x@PEDOT:PSS flexible pressure sensor array and Ti₃C₂T_x/AgNWs/Tissue dual-function sensors were used as human-machine interaction interfaces,respectively.Base on this,pulse wave wireless monitoring system,pressure array sensor imaging system and dual function（body distance/pressure）monitoring and display system are developed.The pulse wave wireless monitoring system can measure and display human pulse wave signals and carry out health analysis;the pressure array sensor imaging system can carry out real-time imaging of the pressure array;the dual-function monitoring and display system can detect and display the distance or pressure from human fingers to the sensor.Each sensor integrated system has the characteristics of small size and high integration,which shows the broad prospect of Ti₃C₂T_x MXene based flexible sensor integrated system in the field of human-computer interaction.