TiO2薄膜光催化体系中羟基自由基的水杨酸分子探针法测定  

Salicylic acid as a molecular probe to determine hydroxyl free radicals in a TiO_2 thin films photocatalytic system

作　　者：任学昌[1,2] 史载锋[2] 孔令仁[2] 展宗城[1] 

机构地区：[1]兰州交通大学环境与市政工程学院,兰州730070 [2]南京大学环境学院,污染控制与资源化研究国家重点实验室,南京210093

出　　处：《环境科学学报》2008年第4期705-709,共5页Acta Scientiae Circumstantiae

基　　金：兰州交通大学“第四批‘青蓝’人才工程资助”项目(NoQL-06-04-A);甘肃省自然科学基金项目(No3ZX062-B25-009);国家“863”项目(No2002AA601250)~~

摘　　要：以水杨酸为分子探针物,以分光光度法测定了纳米TiO2薄膜光催化体系中产生的羟基自由基(.OH).结果表明,水杨酸的自然氧化程度较低,可以作为分子探针测定.OH的产生;实验中最佳的光照时间为60min;水杨酸浓度对·OH的测定影响较大,其最佳值为50mg·L-1;pH值对.OH的测定影响较大,最佳值为6;最佳实验条件下,分析得到.OH的稳态浓度为1.68×10-14mo·lL-1.Hydroxyl free radical production in a titanium dioxide film photocatalytic system was determined by a spectrophotometric method using salicylic acid as the molecular probe. Salicylic acid is scarcely oxidized under natural conditions, so it can serve as a probe to determine the concentration of hydroxyl radical produced during photocatalysis. The optimal illumination time was determined to be 60 min. The concentration of salicylic acid and pH greatly affected the determination of hydroxyl free radicals. The optimal concentration of salicylic acid was 50 mg·L^-1 and optimal pH was 6. Under the optimal experimental conditions, the steady state concentration of hydroxyl free radical was 1.68 × 10^-14 mol·L^-1.

关 键 词：纳米TIO2薄膜 分光光度法测定 羟基自由基 光催化体系 分子探针 水杨酸 探针法 最佳实验条件 

分 类 号：X703[环境科学与工程—环境工程] TB383[一般工业技术—材料科学与工程]