Ag/TiO_2光催化薄膜清除乙烯气体的研究

Study on the photocatalytic decomposing ethylene by Ag/TiO_2 thin film

乙烯对果蔬的生长有积极的作用,它可以促进果蔬的成熟,使其变得香甜可口。但果蔬成熟后乙烯的存在又可以加速果蔬的熟化程度,使其变得脆弱、易腐烂。因此,清除乙烯将对果蔬保鲜产生积极的影响。本文采用溶胶凝胶方法制备了TiO2及Ag/TiO2薄膜。利用气相色谱法通过在自制的反应器内进行检测清除乙烯的实验,比较了TiO2薄膜和Ag/TiO2薄膜的光催化清除乙烯性能。结果发现,TiO2薄膜有较好的光催化清除乙烯性能,掺杂适量的Ag后,Ag/TiO2薄膜有更好的清除乙烯性能。本文还用XRD、SEM对TiO2及Ag/TiO2薄膜的形貌、物相结构、颗粒尺寸进行了表征分析并对实验结果进行了讨论。

The active effect of ethylene on the growth of fruits and vegetables has been indicated. The ethylene can accelerate ripening of fruits and vegetables and make them taste well. But the ethylene can also make them ripen in excess and rot them accelerately during the period of the storage of the fruits and vegetables. So it is very important to decompose the ethylene for the storage of the fruits and vegetables. In this paper TiO2 and TiO2 thin films doped with Ag were prepared by sol-gel method. The tests of decomposing the ethylene were done in photocatalytic reactor by GC method and the photocatalytic activities of decomposing ethylene were compared between Ag/TiO2 and pure TiO2 thin films. The results show that the ethylene can be decomposed by TiO2 films and the results also indicate that the Ag/TiO2 thin films have better photocatalytic ability than TiO2 thin films. The surface morphology, crystal phase structure and particle size of TiO2 and Ag/TiO2 thin films were studied by means of XRD and SEM.