In view of the threat of hydrogen sulfide(H

2

S)gas to human health and environmental pollution

high-performance composite gas-sensitive materials are designed and prepared by precious metal doping.The sensitive materials are prepared by hydrothermal method

and the surface morphology of the prepared tungsten oxide nanowires is analyzed by electron microscopy.It is concluded that various gas-sensitive properties of the sensitive materials can be further improved.Then

MEMS technology is used to study the chip structure design and processing of the micro-hotplate and electrode

optimize the device structure

improve the electrode utilization

reduce the volume of the sensor

and improve the heating efficiency of the micro-hotplate.Finally

the performance of the gas sensor is tested.The test result shows that the sensor has a good response in the volume fraction range of (1~1000)×10

-9

and the response time and recovery time at volume fraction of 100×10

-9

are 24s and 36s

respectively.