多孔TiO_2薄膜电极/泡沫镍硬模板制备及其光电催化性能  

Photoelectrocatalytic activities of porous TiO_2 film electrode coated on foam nickel substrates prepared by a hard-template method

作　　者：曾孟雄[1] 李佑稷[1] 刘晨[1] 李雷勇[1] 陈伟[1] 

机构地区：[1]吉首大学化学化工学院,吉首416000

出　　处：《环境科学学报》2013年第5期1256-1263,共8页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金项目(No.51172092);湖南省教育重点项目(No.11A093);新世纪优秀人才支持计划~~

摘　　要：以泡沫镍为载体,活性炭为造孔剂,采用硬模板法制备泡沫镍负载多孔TiO2薄膜(Porous TiO2 films/foam niclel,PTFN)电极,并利用XRD和SEM等测试手段对其结构进行表征.同时,通过亚甲基蓝溶液的光电催化降解反应,对其光电催化活性进行评价,并探讨阳极偏压、通气速率、亚甲基蓝初始溶液浓度和活性炭造孔剂量对降解效率的影响规律.结果表明:相对于未加模板造孔剂的TiO2薄膜电极的光电催化性能,泡沫镍负载多孔TiO2薄膜具有更好的光电催化性能,原因是高比表面积电极有利于为光电催化提供高浓度的亚甲基蓝分子,使反应速率加快;另外,存在最佳的光电催化降解条件,即当外加阳极偏压为3V,通气速率为40L·h-1,n(活性炭造孔剂量):n(前驱体中钛)(即C/Ti)为10%,亚甲基蓝溶液初始浓度为1mg·L-1时,光电催化降解效率最高.同时,研究发现,亚甲基蓝在光电催化降解过程中,通过自由基的氧化发生了CN键的断裂去甲基化,最后被降解为H2O、CO2和SO42-、NO3-、Cl-离子.The porous TiO2 film electrode coated foam nickel （PTFN） is prepared by a hard-template method by using activated carbon as the poreforming agent and foam nickel as the substrate. The PTFN was characterized by x-ray diffraction （XRD） , scanning electron microscopy （SEM） , etc. , and its photoelectrocatatytic activity was evaluated by degradation of methylene blue （MB） solution. Meanwhile, the effects of anode bias voltage, ventilation rate, initial concentration of MB and amount of carbon-pore-forming agent on photoelectrocatalytic performance were investigated. The results show that PTFN has higher photoeleetroeatalytic activity for the MB degradation than the non-porous TiO2 film coated foam nickel substrate, as electrode with high surface area is capable in providing high MB concentration to be degraded and therefore a faster reaction rate. Under 3 V of bias voltage, 40 L·h ^-1 of ventilation rate and 1 mg· L^-1 of MB initial concentration with a mole ratio of activated carbon to Ti element in precursor of 10% , the photoelectrocatalytic degradation efficiency of methylene blue is the highest. Meanwhile, it is also found that MB molecules are oxidized by free radicals in the process of photoelectrocatalytic degradation and demethylated in the C =N bond rupture, and finally degraded into H2O, CO2 and ions such as SO4^2 - ,

关 键 词：泡沫镍 多孔TiO2薄膜 光电催化 亚甲基蓝降解 

分 类 号：X703[环境科学与工程—环境工程] O643.36[理学—物理化学]