| With the increase of people's requirements for the quality of life and the rapid development of the national economy,the topic of pollutant gas detection is getting hotter and hotter.Different types of gas-sensitive sensors are gradually entering the market.Up to now,the mainstream gas sensor materials are multi-element metal oxide semiconductor materials.These oxide semiconductor materials have the advantages of simple preparation,low cost,and low power consumption,and have received extensive attention.With the rapid development of industry,various organic solvents are widely used in the manufacture of various industrial products,such as ethanol,acetylacetone,and formaldehyde.Organic solvents are volatile.When people are exposed to ethanol,acetylacetone,formaldehyde and other gas environments for a long time,they will have various discomforts.Among them,wine-sensitive detectors have already begun commercial applications.The research and development of new wine-sensitive materials has aroused the interest of the majority of scientific researchers.In life,excessive drinking can damage people's islet function and induce various chronic diseases.It is very painful for people who have been in an ethanol environment for a long time.Therefore,it is of great significance for the development of sensitive wine-sensitive test equipment.Acetylacetone is a colorless or light yellow transparent liquid.When it encounters light,it will generate resin and turn brown.Acetylacetone can be dissolved in various organic solvents in our lives.It is commonly found in various coatings and lubricants.It can also be used as an additive for gasoline and lubricating oil.It is precisely because acetylacetone exists in the production process of various daily necessities that there will be many residues on various industrial products.Therefore,people's nervous system and respiratory system will be damaged when people are in contact for a long time or absorbed through the skin.Acetylacetone is a colorless or light yellow transparent liquid.When it encounters light,it will generate resin and turn brown.Acetylacetone is slightly soluble in water,chloroform,alcohol,acetone and other organic solvents.It is commonly used in various coating desiccants and lubricants,and can also be used as an additive for gasoline and lubricating oil.It is precisely because the common acetylacetone in life is present in the production process of various daily necessities,it produces various uncomfortable feelings for people's long-term inhalation or absorption through the skin.In this experiment,the gas-sensitive properties of the micro-plane interdigital electrode gas sensor to alcohol and acetylacetone were mainly studied,and the nanocomposite materials needed in the experiment were prepared.The response of nanocomposites to some other reducing gases,such as acetone,formaldehyde and other gases,was explored.For this reason,in this experiment,the gas-sensitive properties of the micro-plane interdigital electrode gas sensor to ethanol and acetylacetone were mainly studied,and different nanocomposite materials were prepared.And explored the response characteristics of nanocomposite materials to other reducing gases,such as acetone,formaldehyde and other gases.This paper mainly includes the following aspects of work:1.A series of Fe-doped In2O3 nanomaterials were prepared by a simple sol-gel method.Nanoparticles with In:Fe=1:1,In:Fe=4:1,In:Fe=6:1,and In:Fe=8:1 were prepared.The sintering temperature was 600? and the time was 4h.When In:Fe=1:1,6:1,8:1,the response of the device to alcohol under heating at 120? is:6.363,6.875,and 6.895.By testing the UV-visible light absorption spectrum of the material,it can be known that when In:Fe=4:1,the band gap is 1.75eV.The device responds very well to ethanol and acetone.The best detection temperatures for these two gases correspond to 120?and 140?,respectively.When the gas concentration is 30ppm,the sensitivity of the device is 7.24 and 11.45,respectively.The changes in the gas-sensing performance of the gas sensor when the light power is 100mw 370nm ultraviolet light and 400nm and 430nm visible light are irradiated.For nanomaterials with a molar ratio of In:Fe=4:1 under 370nm ultraviolet light,the optimal response temperature decreased from 120?to 110?,and the response to 30ppm ethanol increased from 7.24 to 9.5.When the element is irradiated with 420nm light,the response becomes 8.025.This is because under the condition of light irradiating the gas sensor,the light can clean the adsorbed oxygen on the surface of the gas sensor material in time.This acceleration process allows the gas-sensitive material to make the most of the surface of the gas-sensitive element and reduce the barrier height of the surface.At the same time,the probability of electron tunneling increases,resulting in a change in the response of the element under light irradiation.2.The Zn element-doped CeO2 metal oxide nanomaterial was made by a simple sol-gel method.The gas sensitivity of the material under different annealing temperatures of 400?,600?,800?,and 1000? was compared.It is found that when the annealing temperature is At 1000?,the gas sensitivity of nanocomposites is the best.It has high selectivity and response to 30ppm acetylacetone,with a response of 29.5.For other gases,the responses of 30ppm formaldehyde,30ppm acetone,and 30ppm ethanol are 7.25,8.23 and 2.34,respectively.The band gap of the material was measured with an ultraviolet-visible-near-infrared spectrophotometer,the band gap size was 3.35eV,and the device was irradiated with ultraviolet light(wavelength 370nm,power 100mw),it was found that the response of the device to 30ppm acetylacetone increased to 41.3,the response time It changed from 20s to 16s,and the recovery time changed from 32s to 28s.Under ultraviolet light irradiation,the response of the component to 30ppm acetone,30ppm ethanol,and 30ppm formaldehyde was tested,and the response sizes corresponded to 10.6,5.24,and 7.4.The sol-gel method was used to prepare Fe-doped In2O3/CeO2-doped nano powder particles.Three materials with different molar ratios were prepared in the experiment,and the corresponding molar ratios were In:Ce:Fe=0.25:0.75.:1.In:Ce:Fe=0.5:0.5:1,In:Ce:Fe=0.75:0.25:1,the annealing temperature of the material is 600?,and the annealing time is 4h.The XRD pattern and SEM topography of the material were tested in the experiment.The ultraviolet,visible and infrared light absorption spectrum of the material was tested,and the band gap was 1.65 eV.Through measurement,it is found that when the molar ratio of In:Ce:Fe=0.25:0.75:1,the material has the largest response to acetylacetone,which is much higher than other materials with molar ratios.The response to acetylacetone at a concentration of 30ppm is 30.526,and the best response temperature is 100?.The three materials were irradiated with 370nm,400nm,and 430nm light,and the optical power was 100mw.For the material with the molar ratio of In:Ce:Fe=0.25:0.75:1,the response to 30ppm gas acetylacetone was respectively 52.025,47.258 and 36.013.For the material with the molar ratio of In:Ce:Fe=0.5:0.5:1,the corresponding gas-sensing response is 23.487 in the absence of light,and the response to acetylacetone under 370nm,400nm and 430nm light(power 100mw)They are 24.241,31.4 and 34.23 respectively.For the material S3 with a molar ratio of In:Ce:Fe=0.75:0.25:1,the corresponding gas-sensitivity response is 9.025 under no light conditions.Under 370nm,400nm and 430nm light(power 100mw),it is The responses of acetylacetone were 9.31,12.102,and 12.015. |
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