纳米二氧化钛薄膜电极的制备、改性及电催化还原L-胱氨酸的应用研究

发布时间：2018-03-05 05:11

本文选题：Ti/anoTiO_2薄膜电极　切入点：溶胶凝胶　出处：《安徽理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：L-半胱氨酸是一种具有生理功能的含巯基的氨基酸,在生物医药、食品行业以及生物化妆品领域被广泛应用。用电催化还原L-胱氨酸的方式合成L-半胱氨酸是应可持续发展的迫切需要而生的一种绿色化工技术。目前电催化还原L-胱氨酸采用传统的Pb板,电极催化活性不高且容易造成Pb2+污染,影响产品质量,因此寻找一种高催化性能且性能稳定的电极是急需解决的问题。Ti02半导体材料在光电催化方面有着非常好的应用前景,本文以钛酸四正丁酯[Ti(OC4H9)4]和稀土的硝酸化合物为原料,采用超声辅助溶胶-凝胶法制备了稀土La和Ce共掺杂的Ti02薄膜电极(Ti/Ln-nanoTiO2薄膜电极)以及非稀土Sn和稀土La、Ce多掺杂的C薄膜电极(Ti/Ln-nanoSnO2-TiO2薄膜电极)。利用SEM、XRD、XPS以及电化学测试(CV、EIS)等检测手段对掺杂改性后的Ti02薄膜电极进行了表征。主要研究成果如下： 1创新了溶胶-凝胶法,首次采用超声辅助溶胶-凝胶法进行Sn (SnCl4·5H2O)掺杂制备し复合材料。在实验中,研究不同超声时间对Ti/nanoTiO2膜电极的电催化效果的影响,CV测试结果表明：在超声15分钟,频率为100W时,得到的し薄膜电极的电还原活性最高。同时研究了Sn掺杂量对Ti/nanoSnO2-TiO2膜电极的电催化效果的影响,在优化条件下,当Sn掺杂量为1%时,得到的Ti基SnO2-TiO2复合半导体材料膜电极的电催化还原效果最好,相对于未超声的电极有更好的催化活性。通过SEM表征发现,其表面颗粒分布相较于未超声的电极更加均匀。 2在优化条件下,以六水合硝酸镧(La(NO3)3·6H2O)以及六水合硝酸铈(Ce(NO3)3·6H2O)为稀土掺杂来源,成功实现了Ti02薄膜电极的镧系共掺杂改性,制备了不同掺杂量的Ti02薄膜电极(Ti/Ln-nanoTiO2薄膜电极)。研究结果发现：在lmol/L盐酸溶液中的CV图中,当引入的Ce:La:Ti的摩尔比为0.5：0.5：100,所制备的Ti/Ln-nanoTiO2薄膜电极活性是空白电极的6.0倍。 3在优化条件下,以六水合硝酸镧(La(NO3)3-6H2O)、六水合硝酸铈(Ce(NO3)3·6H2O)为稀土镧源以及五水合氯化锡(SnCl4·5H2O)为Sn源成功实现了Sn、Ce、La三掺杂改性TiO2,同时制备了不同掺杂组分的Ti02薄膜电极(Ti/nanoSnO2-TiO2、Ti/Ce-nanoSnO2-TiO2、Ti/La-nanoSnO2-TiO2、Ti/Ln-nanoTiO2、 Ti/Ln-nanoSnO2-TiO2薄膜电极)。研究结果发现：当引入的Sn:Ce:La:Ti的摩尔比为1：0.5：0.5：100时,所制备的Ti/Ln-nanoSnO2-TiO2薄膜电极活性最高,是空白电极的9.0倍。 4利用Ti/Ln-nanoTiO2薄膜电极,研究了其在L-胱氨酸盐酸、SnCl2混合溶液中的电催化还原特性及其反应机理,结果表明：Ti/Ln-nanoTiO2薄膜电极在L-胱氨酸SnCl2溶液中的最高峰电流密度为50mA·cm-2,电催化活性是空白Ti/nanoTi02薄膜电极的4.5倍左右。使用Ti/Ln-nanoTiO2薄膜电极进行实验室电解合成实验,得到在最佳实验条件下的电流效率为93.7%,电解产率为91.6%。 5利用Ti/Ln-nanoSnO2-TiO2薄膜电极,研究其在L-胱氨酸溶液中的电催化还原特性及其反应机理,结果表明：Ti/Ln-nanoSnO2-TiO2薄膜电极(Sn:Ce:La:Ti=1：0.5：0.5：100)在L-胱氨酸溶液中的最高峰电流密度为30mA-cm-2,电催化活性是空白Ti/nanoTiO2薄膜电极的4.5倍左右。使用Ti/Ln-nanoSnO2-TiO2薄膜电极进行实验室电解合成实验,在最佳实验条件下,电流效率为85%,L-半胱氨酸盐酸盐产率为80%。
[Abstract]:L- is a kind of physiological function of cysteine thiol containing amino acids in biological medicine, food industry and bio cosmetics have been widely applied. The electrocatalytic reduction of L- cystine synthesis L- cysteine is a kind of green chemical technology should be an urgent need for the sustainable development of the students. The electrocatalytic reduction of L- cystine amino acid by traditional Pb board, catalytic activity is not high and it is easy to cause the pollution of Pb2+, affecting the quality of the products, so to find a high catalytic performance and stable performance of the electrode is urgent problem of.Ti02 semiconductor material has a very good prospect in photoelectric catalysis, using butyl titanate four [Ti (OC4H9 4]) and rare earth nitrate compounds as raw materials, Ti02 thin film electrode La and rare earth doped Ce were synthesized by ultrasonic assisted sol-gel method (Ti/Ln-nanoTiO2 films) and non rare earth and Sn Rare earth La, Ce multi doped C thin film electrode (Ti/Ln-nanoSnO2-TiO2 thin film electrode). SEM, XRD, XPS and electrochemical detection (CV, EIS) and other detection methods were used to characterize the modified Ti02 film electrode.
1 innovation of the sol gel method, for the first time by ultrasonic assisted sol-gel method Sn (SnCl4 - 5H2O) were prepared by doping. Composite materials. In the experiment, influence the electrocatalytic effect of different ultrasonic time on Ti/nanoTiO2 membrane electrode, CV test results showed that ultrasound in 15 minutes, at the frequency of 100W. The environmental film electrode electrochemical reduction. The highest activity studied electrocatalytic effect of Sn doping on Ti/nanoSnO2-TiO2 film electrode, under the optimized conditions, when the Sn content was 1%, the electro catalytic Ti based SnO2-TiO2 composite semiconductor film electrode obtained by reduction of the best effect, with respect to the catalytic activity of the electrode without ultrasound the better. The SEM characterization showed that the particle size distribution of surface electrode compared to the non ultrasound is more uniform.
2 under the optimized conditions, with six hydrated lanthanum nitrate (La (NO3) 3 - 6H2O) and six hydrated cerium nitrate (Ce (NO3) 3 - 6H2O) for rare earth doped source, the successful implementation of the Ti02 thin film electrode doped with lanthanide modified Ti02 thin film electrodes were prepared with different doping amount (Ti/ Ln-nanoTiO2 thin film electrode). The results showed that in lmol/L hydrochloric acid solution in the CV diagram, the introduction of Ce:La:Ti when the molar ratio is 0.5:0.5:100, Ti/Ln-nanoTiO2 film electrode preparation is 6 times that of the control electrode.
3 under the optimized conditions, with six hydrated lanthanum nitrate (La (NO3) 3-6H2O), cerium nitrate six hydrate (Ce (NO3) 3 - 6H2O) for rare earth lanthanum source and five tin chloride hydrate (SnCl4 - 5H2O) Sn source for the successful implementation of the Sn, Ce, TiO2 modified La three doped, at the same time preparation of Ti02 thin film electrodes with different doping components (Ti/nanoSnO2-TiO2, Ti/Ce-nanoSnO2-TiO2, Ti/La-nanoSnO2-TiO2, Ti/Ln-nanoTiO2, Ti/Ln-nanoSnO2-TiO2 thin film electrode). The results showed that: when the molar ratio of the Sn:Ce:La:Ti introduced 1:0.5:0.5:100, the prepared Ti/Ln-nanoSnO2-TiO2 thin film electrode was the highest, is 9 times that of the control electrode.
4 using Ti/Ln-nanoTiO2 thin film electrode was investigated in L- cystine hydrochloride, redox properties and reaction mechanism, catalytic SnCl2 mixed solution. The results showed that the peak current density of Ti/Ln-nanoTiO2 thin film electrode in L- cystine SnCl2 solution for 50mA and cm-2, the electrocatalytic activity is about 4.5 times of blank Ti/nanoTi02 thin film electrode the use of Ti/Ln-nanoTiO2 thin film electrode of electrolytic synthesis experiment, current efficiency was obtained under optimal conditions was 93.7%, electrolytic yield is 91.6%.
5 using Ti/Ln-nanoSnO2-TiO2 thin film electrode on the L- cystine solution in the electrocatalytic characteristics and reaction mechanism, the results show that the Ti/Ln-nanoSnO2-TiO2 thin film electrode (Sn:Ce:La:Ti=1:0.5:0.5:100) peak current density in L- cystine in the solution is 30mA-cm-2, the electrocatalytic activity is about 4.5 times of blank Ti/nanoTiO2 thin film electrode using Ti/Ln-nanoSnO2-TiO2 thin films. Electrode for electrolytic synthesis in laboratory experiments, the optimum experimental conditions, the current efficiency was 85% and the yield of 80%. L- cysteine hydrochloride

【学位授予单位】：安徽理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：O646.54;TB383.1

【参考文献】