利用60Co-γ射线辐照使TiO2改性后对乙烯的催化降解
效果
郑森鸿;叶盛英;黄迅;沈生文
【期刊名称】《农业工程学报》 【年(卷),期】2013(000)020
【摘要】Horticultural products are abundant in China. However, a large amount of them were deteriorated due to the lack of appropriate storage and transport technology, resulting in a huge waste. Ethylene gas is one of the main reasons which cause the deterioration of horticultural products in storage. Nanometer TiO2 photoelectrocatalysis technology is a new technique developed in recently. TiO2, under UV light, can degrade organics such as ethylene, so it provides a potentially effective method for keeping free products. However, in practical applications, the mutual composite happens easily, which shorts the lives of the carriers and limits the application of TiO2. The only solution for this problem is to decrease the compositing rate of photoinduced electrons and the holes by modifying the nanometer-sized TiO2. Developing modified method is also a hot topic of researchers here in China and abroad. 60Co-γ ray irradiation reduction technique can modify TiO2 and make it more activity for the catalytic degradation of organics. In order to investigate the effect of TiO2, irradiated by 60Co-γray
and
loaded
with
activated
carbon
fibers
(ACF),
on
photoelectrocatalytic degradation of ethylene in the environment of cold storage, the TiO2/ACF photoelecrorcatalysis materials was deposited with nano-Ag (Ag-TiO2/ACF) and irradiated by 60Co-γray. The effects of 60Co-γray irradiation modified TiO2 (10, 15, 20, 25, 30, 40 kGy) on the photoelectrocatalytic degradation rate of ethylene were investigated in a simulated cold storage environment for horticultural product. X-ray diffractometer and X-ray photoelectron spectroscopy were used to characterize the prepared TiO2. Results from X-ray diffraction showed that: the crystal size has reduced. The percent of anatase decreased from 84.97%in pure TiO2 to 82. 98%in TiO2 treated with a 40 kGy irradiation dose. Result of X-ray photoelectron spectroscopy indicated that the amount of Ti3+, hydroxyl oxygen which have better catalytic activity increased after irradiation. The percentage of Ti3+in total Ti element rose from barely detected to 3.1%. The hydroxyl oxygen increased from 18.83% to 35.8%. Both X-ray diffraction and X-ray photoelectron spectroscopy results favored the separation rate of electron-hole, the redox ability and catalytic activity of TiO2. The apparent rate constant for photoelectrocatalysis degradation of ethylene was increased as irradiation dose increased up to 25 kGy due to the promotion of catalytic activity of TiO2. However, when the irradiation dose reached 30 kGy, the solution of TiO2 formed precipitate which reduced the specific surface of TiO2 and decreased the apparent
rate constant.%为了解60Co-γ射线辐照且以活性炭纤维（activated carbon fiber，ACF）为载体所负载Ag沉积的TiO2的半导体材料（Ag-TiO2/ACF）对光催化降解冷藏环境中乙烯的影响，在模拟园艺产品的冷藏环境中，研究了不同辐照剂量下的TiO2对乙烯的降解，并利用X射线衍射仪（XRD）及X-射线光电子能谱（XPS）对所制备的光催化材料进行相关的表征分析。表征结果表明：随着辐照剂量的增加，总体上锐钛矿的含量及尺寸减小，Ti3+及羟基氧含量提高，这些变化能使TiO2的催化活性增强。乙烯降解试验结果表明，当辐照剂量小于25 kGy时，乙烯降解速率随辐照剂量的提升而提高；当辐照剂量大于25 kGy时，乙烯降解速率随辐照剂量的提升而下降，可能是辐照能量过高导致TiO2粒子聚集沉淀，催化能力下降。研究结果为 TiO2光催化技术的进一步应用提供了参考。 【总页数】7页(286-292)
【关键词】TiO2;辐照;乙烯;60Co-γ射线 【作者】郑森鸿;叶盛英;黄迅;沈生文
【作者单位】华南农业大学食品学院，广州 510642;华南农业大学食品学院，广州 510642;华南农业大学食品学院，广州 510642;华南农业大学食品学院，广州 510642 【正文语种】中文
【中图分类】S379.2;TB333 【文献来源】
https://www.zhangqiaokeyan.com/academic-journal-cn_transactions-chinese-society-agricultural-engineering_thesis/0201258093984.html
利用60Co-γ射线辐照使TiO2改性后对乙烯的催化降解效果
