| With the rapid development of society and economy in China,the demand for oil and gas resources is increasing day by day,and a large number of environmental and safety problems are associated with oil and gas development.Organic gases containing alkanes,such as methane and propanol,and organic volatiles（VOC）are mostly produced in the whole process of petrochemical production,and these gases seriously endanger human life and property safety.In view of the above toxic and harmful gas timely detection,it is urgent to develop devices with rapid detection capability.As a device specially used to detect gas composition and concentration,gas-sensitive sensor has been widely used in various gas detection fields.In2O3 semiconductor gas sensor has been widely used in practical production and life because of its small size,high sensitivity,simple manufacturing process and other advantages.This kind of semiconductor gas sensor also has some problems such as high operating temperature,weak response recovery ability and low sensitivity in practical application.The key to solve these problems is to quickly and accurately detect these toxic and harmful gases,which is the significance of this study,but also to provide an objective basis for the development of gas sensor,and reduce the risk for the process of oil exploration.In this paper,the idea of preparing different morphologies of indium oxide is proposed.The method used in this idea is mainly hydrothermal method,which can effectively improve the performance of gas sensitive materials.And Ag2O doping was used to improve the gas sensitivity of the material,and then the actual experiments were carried out to verify and analyze the experimental methods,including X-ray photoelectron spectroscopy（XPS）,X-ray diffraction（XRD）,transmission electron microscopy（TEM）,etc.,to characterize the structure and composition of the material.On this basis,the research work of volatile gas detection of oil and gas is also carried out by static experimental method.The research results of this paper include:In2O3 prepared under different conditions,when the doping amount of In and urea is 1:2,the prepared In2O3 product is cubic morphology.When the doping amount of In and urea is 1:5,the In2O3 product is cubic and the inclusion is nanorod flower-like particles.When the molar ratio is reduced to 1:8,the In2O3 products obtained appear as formed nanorod flowers on the cube,and the inclusions are cube cubes.When the molar ratio is 1:10,the In2O3 products appear as chaotic nanorod flowers.When the molar ratio is further reduced to 1:15,In2O3 with the morphology of nanorod flower clusters can still be obtained.During the hydrothermal process,the rod-like morphology was completely preserved.The oriented In2O3 nanoparticles assemble the nanorods into mesoporous structures,and the In2O3 nanorods are polycrystalline.The experimental results show that when the ratio of urea to indium oxide is 1:8,the gas performance is the best,and the sensitivity to the volatile gas of petroleum is the best.In2O3 nanorods have better gas sensitivity than In2O3 nanoparticles.In the study,it was found that180℃belongs to the best working temperature,which can achieve the highest performance,and the sensitivity of 100ppm C3H8 can reach 86.9.When the doping amount of Ag2O is 0.2mol%,the composite Ag2O/In2O3 belongs to the shape of the cube still retained.When the doping amount of Ag2O reached 0.6mol%,more spherical particles were obtained,and there were more gaps and holes between the spheres.When the doping amount of Ag2O is 1.0mol%,the porous spherical particles are obtained,and the pores remain connected.The gas sensitivity test results show that the gas sensitivity performance of single substance In2O3 is improved after doping Ag2O,which has certain advantages compared with the original single substance.The sensor based on Ag2O/In2O3 can achieve the highest performance at 145℃,while the sensor with 0.6mol%Ag2O/In2O3 shows the highest sensitivity to C3H8 with a sensitivity of 212. |
