电极制备及其三维光电催化性能的研究

发布时间：2018-01-19 21:46

  本文关键词： 三维电极 微弧氧化 光电催化 粒子电极　出处：《沈阳理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：三维光电体系由于光电协同的有效作用,Ti O2的光催化活性得到充分发挥,有效提高对有机污染物的降解效率。本文选用蛭石作为载体粒子,利用溶胶—凝胶法制备Ti O2/蛭石,Ti O2/蛭石与石墨组成粒子电极,分别以溶胶凝胶法制备的钛网电极(钛网光电极)和微弧氧化法制备的钛网电极(钛网膜电极)为主电极,石墨片为对照阴极,亚甲基蓝溶液为目标降解物,支持电解质为无水硫酸钠溶液,固定光源为20w紫外灯,在恒定外电压的作用下,研究三维光电催化体系对亚甲基蓝溶液光电催化降解的效率。实验研究了三维电极光电催化性能的影响因素,Ti O2/蛭石与石墨粒子电极和钛网光电极组成的三维光电体系的实验结果表明:当二氧化钛光电极的煅烧温度为550℃,Ti O2/蛭石粒子的煅烧温度500℃,石墨0.8 g,Ti O2/蛭石0.2 g,外接电压2 V,电极距离3 cm,无水硫酸钠溶液浓度0.02 mol/L,亚甲基蓝溶液浓度5mg/L,p H=10。三维光电催化实验对亚甲基蓝的脱色率为51.9%。负载Ag离子和Cu离子的钛网光电极实验中,Ag离子负载量为1.0%,对亚甲基蓝降解效果最好,脱色率为59.6%;Cu离子负载量为0.75%时,对亚甲基蓝的脱色率为53.2%。当以Ti O2/蛭石与石墨粒子电极和钛网膜电极组成的三维光电体系的实验结果表明:(1)当6 g/L的磷酸钠为电解液,微弧氧化反应时间为5 min,光电催化对亚甲基蓝的脱色率是40.15%。(2)在负载Ag离子和Cu离子的钛网膜电极实验中,钛网负载Ag+和Cu2+的最佳修饰法是再微弧氧化法,光电催化反应持续60min对亚甲基蓝脱色率分别为42.56%和39.55%,当Cu2+浓度为0.01 mol/L,再微弧氧化时间为7 min时,亚甲基蓝的脱色率最佳为44.01%,当Ag+浓度为0.01mol/L,电沉积时间为5 min时,亚甲基蓝的脱色率最佳为54.33%。(3)研究了微弧氧化钛网电极、再微弧氧化负载Cu2+和Ag+电极和对甲醛的降解实验,结果表明光电催化120 min的降解率分别为15.7%、21.9%和32.1%,微弧氧化负载Cu2+和Ag+的电极都高于只微弧氧化的钛网电极,说明Cu2+和Ag+离子对电极的修饰均提高了体系催化效率。
[Abstract]:The photocatalytic activity of TIO _ 2 in three-dimensional photovoltaic system has been fully developed due to the effective effect of optoelectronic coordination, and the degradation efficiency of organic pollutants has been effectively improved. In this paper, vermiculite is selected as the carrier particle. TIO _ 2 / vermiculite / vermiculite / vermiculite particle electrode was prepared by sol-gel method. The titanium mesh electrode (titanium mesh photoelectrode) prepared by sol-gel method and titanium mesh electrode (titanium omentum electrode) prepared by micro-arc oxidation method were used as main electrode respectively. Graphite sheet was used as control cathode and methylene blue solution as target degradation material. The supporting electrolyte is anhydrous sodium sulfate solution and the fixed light source is 20w UV lamp under the action of constant external voltage. The efficiency of photocatalytic degradation of methylene blue solution by three-dimensional photocatalytic system was studied. The factors influencing the photocatalytic performance of the three-dimensional electrode were studied experimentally. The experimental results of 3D photovoltaic system composed of TIO _ 2 / vermiculite, graphite particle electrode and titanium mesh photoelectrode show that the calcination temperature of TIO _ 2 photoelectrode is 550 鈩，

本文编号：1445647