【作者】 王国强；

【导师】 李子亨；

【作者基本信息】 吉林大学 ， 凝聚态物理， 2016， 硕士

【摘要】 氧探测在工业控制、环境监测、医学以及人们日常生活等方面都有广泛应用,因而发展快速、灵敏、高效的氧气检测方法与技术具有重要意义。血红素是人体和哺乳动物体内血液中必不可少的物质,主要负责体内氧气的运输和传递。氯化血红素(铁卟啉)是人工合成血红素的氯化物,其化学性质与血红素相似。作为氧气的载体,在一定条件下可以探测氧气。近年来,铁卟啉修饰膜电极在催化及探测氧气方面表现出很好的应用前景。本文用LB技术制备了铁卟啉LB膜并对其进行一系列不同条件热处理,实现了其电化学性能优化。通过紫外可见吸收光谱及红外光谱进行分析,并对其红外峰进行指认,分析热处理对铁卟啉LB膜红外峰的影响;以优化的铁卟啉LB膜为工作电极,用三电极系统对其进行循环伏安扫描,考察了电极对不同浓度溶解氧的探测性能;考察了测试体系含有不同浓度铁卟啉时对LB膜电极氧探测效果的影响。结果表明,铁卟啉LB膜在经过不同条件热处理优化后,铁卟啉分子与ITO玻璃基底结合紧密有序,导致其B带的紫外可见吸收峰蓝移,Q带吸收峰减少。红外吸收光谱特征峰的数量随着热处理温度和时间的变化发生规律性的变化。热处理温度为60°C,热处理时间为3小时的样品因卟啉环形变,具有更好的电化学活性;选择该热处理条件的样品对含有不同浓度溶解氧的KCl溶液进行溶解氧探测,随着溶解氧浓度的线性增加,循环伏安曲线电流随着浓度的增加而呈现规律性的增加,不同的循环伏安曲线之间的区分度很好,响应也较快;当测试体系含有铁卟啉分子时,溶液中的铁卟啉与电极上的铁卟啉通过轴向配位形成聚合物,不同浓度的循环伏安曲线之间区分度降低,响应速度降低。紫外可见吸收光谱表明,铁卟啉LB膜电极探测溶解氧时,LB膜上的卟啉分子会捕获溶液中的氧,再与溶液中的自由移动的卟啉分子结合,形成了三明治结构的氧加合物。进一步的实验表明,用电化学沉积方法得到的铁卟啉膜电极对于溶解氧的探测响应速度低、区分度低而且线性也不好。这说明铁卟啉LB膜电极对于溶解氧检测具有明显的优势。更多还原

【Abstract】 Oxygen detecting has been widely applied in in the industrial control, environmental monitoring, medical and people’s daily life. Thus developing rapid, sensitive and efficient oxygen detecting method and technology is of great significance. Heme is the essential substances in the human body and mammal body blood, which is mainly responsible for transporting and transferring the body oxygen. Hemin(porphyrins) is the synthesized chloride of heme which is similar to heme.it can also detecting oxygen in some cases. And the hemin modified electrodes are playing an important role in detecting oxygen.In this paper, iron porphyrins LB film was prepared and a series of different conditions of heat treatment were used to optimize its electrochemical performance. The UV-visible absorption spectrum and infrared spectrum was obtained. The infrared peaks was assigned. Use the three-electrode system to character the optimized iron porphyrins LB films which examines the properties in detecting the different concentration of dissolved oxygen in KCl solution to imitate animal body in-situ test. Then the electrode was examined in KCl solution containing different concentrations of iron porphyrins to evaluate the influence on detecting oxygen.The results showed that iron porphyrin molecules and ITO glass electrode combined tightly and orderly after the optimized conditions of different heat treatment which causing B band UV-vis absorption spectrum blue shift and Q band absorption peak decreases. The number of the infrared absorption spectrum peaks changed as the heat treatment temperature and time changing regularity. The infrared peaks was at most when it was heat treatment at 60°C for 3 hours. Selecting the sample with the fitted treatment to detect the different concentration dissolved oxygen in KCl, it indicated that cycle voltammogram curve increased regularly change with the linear change of the concentration of dissolved oxygen. The CV curve can be separate from each other and response fast. The iron porphyrins on the electrode form the polymer with the iron porphyrins in the solution by the axial coordination when the solution containing iron porphyrins. The discrimination and the response rate reduced. The UV-visible absorption spectrum showed that the oxygen would be captured by the iron porphyrins on the electrode then combining the dissociative iron porphyrins formed the sandwich structure polymer.Further experiments showed that the electrode prepared by the LB technology had a better discrimination and response faster than the electrode prepared by the chemical deposition method, which clarified the LB iron porphyrins films had obvious advantage in detecting dissolved oxygen.更多还原