Preparation Of Indium-based (In₂O₃, In₂S₃) Nanomaterials And Their Gas-sensing And Photocatalytic Propertie

With the continuous development of social economy,environmental problems have prompted people to explore new solutions.In the process of the rapid development of industry,the identification of poisonous and harmful gases in the environment has become one of the problems that must be solved in the development of today’s society.The appearance of gas sensor has opened up a precedent for solving this problem.Compared with other detection technologies（such as infrared spectroscopy,gas chromatography,ultraviolet absorption and chemiluminescence,etc）,gas sensors have significant advantages in detecting toxic and harmful gases in the air.On the other hand,among many environmental pollutants,organic pollutant has complex composition,difficult to degrade,high toxicity,high emissions,causing great harm to the natural environment and human health.At present,among various water pollution treatment methods,semiconductor photocatalysis technology has gradually become a hot research topic due to its advantages of low energy consumption,complete degradation and reusable,among which semiconductor photocatalysts represented by Ti S₂and WS₂have received wide attention.However,due to their low optical efficiency,their practical application is limited.Based on this,this paper builds a model based on indium-based semiconductor nanomaterials（In₂O₃and In₂S₃）,designs and prepares an efficient gas sensor and photocatalyst,the main research contents are as follows:（1）Ag-In₂O₃hollow nanospheres（Ag-In₂O₃HNSs）were synthesized by ultrasonic chemistry and their sensing properties for triethylamine were investigated.The results show that the Ag-In₂O₃hollow nanospheres triethylamine（TEA）vapor has remarkable selectivity and ultra-high sensitivity.Compared with the original In₂O₃hollow nanospheres（In₂O₃HNSs）,Ag-In₂O₃hollow nanospheres improve the sensing response from 13.74 to 276,and shorten the response/recovery time from 34/49 s to 25/37 s,and show good stability and selectivity.（2）Indium sulfide-graphene quantum dot composites（In₂S₃/GQDs）were prepared by hydrothermal method.The results showed that In₂S₃/GQDs composites had a good degradation effect on methylene blue solution of simulated sewage,and In₂S₃/GQDs-2 showed the best photocatalytic effect.For comparison to pure In₂S₃,the combined effect between GQDs and In₂S₃generally enhanced the adsorption-photocatalytic ability of In₂S₃/GQDs nanocomposites.It’s ascribed to the abundant active sites formed at the junction interfaced and good photo-excite charge carrier separation,finally resulting in improved photocatalytic activity.