A Study Of Flexible Gas Sensor Based On SnO₂ Nanofiber Coated By PDMS

Flexible sensor is considered as a very promising intelligent application component.Flexible sensor has the characteristics of the low cost, soft, good transparency, simple production, biocompatibility, the diversity of sensing system and so on, which makes its future development prospect considerable. In the field of gas sensor, under some special condition, the requirements for gas sensor, and adaption to the development trends of device miniaturization, flexible, transparent, it has become a hot research to put the gas sensor to make to be transparent flexible device in the present. This paper is on the basis of tin dioxide nano fiber membrane to make and study a new type flexible gas sensor to against high selectivity, high response, high sensitivity of hydrogen sulfide gas.This paper main research content is as follows:Preparation of making tin oxide nanowires with stannous chloride solution as precursor, it produce tin oxide nanofibers to adopt the method of electrostatic spinning.Sputter a layer of Ag interdigital electrode on the surface of nanofibers, and a layer of Polydimethylsiloxane(Polydimethylsiloxane, PDMS) on the surface of the electrode and the nanofibers spin coating. Under a certain temperature, PDMS from liquid into solid also fix nanowires and electrode at the same time. Pull the fixed PDMS of nanofibers away from the wafer and clad it, then get flexible gas sensor.This paper, by using good permeability of hydrogen sulfide to PDMS, the sensor is designed into a sandwich structure composed of PDMS, tin oxide nanometer fiber. It not only reduces the influence of stannic oxide nanofibers from the PDMS membrane stress during bending device, but also can isolate the influence of water vapor and air to tin oxide nanowires and the silver electrode. The good permeability of PDMS is the key to resolve performance of the flexible gas sensor. For all coated type flexible gas sensor, this paperstudies the morphology characteristics of the device, the effect on humidity to the performance of devices before and after coating, selective enhancement of device, the changes of oil-gas sensitive response from device bending in the different Angle. In addition, this paper analyses the selective principle that the components were coated later,hydrogen sulfide can go through PDMS and other gas is not easy to go through. This paper studies the performance of cladding layer PDMS modification effect on device, observes whether impact on the performance of the device by changing the crosslinking temperature and concentration of diluted.