摘要
通过溶胶凝胶方法以活性炭(AC)为载体,制备负载型TiO2AC,利用SEM、BET、XRD、Ranme、XPS对TiO2AC的组成、结构、尺寸等特征进行分析和表征,并用紫外灯为光源,通过TiO2AC、TiO2粉末和活性炭与TiO2粉末的混合物对可溶性罗丹明B的光催化降解效果的比较,探讨了TiO2AC的光催化性能.结果表明,负载体中的TiO2是由30～60nm的球形颗粒组成,含有Ti,O,C等3种元素,颗粒间不发生团聚,其中一些C元素是由活性炭载体扩散到TiO2颗粒中的.由于活性炭载体与TiO2的协同作用以及高浓度Ti3+的影响,负载型TiO2AC的光催化活性大.当TiO2AC在250℃空气中热处理2h,再在氮气保护下500℃热处理2h,TiO2的质量分数为(18±0.3)%时,负载型TiO2AC对罗丹明B的光催化降解的表观反应常数k最大,为0.0077min-1.
Photocatalyst of TiO_2-coated activated carbon (TiO_2/AC) was prepared via the sol-gel method from a mixture of TiO_2 sol and activated carbon, which was acted as carrier. The prepared TiO_2/AC was characterized by SEM, BET, Ranme and XPS. The photocatalytic activity of the prepared TiO_2/AC was studied using photocatalytic degradation of aqueous Rhodamine B under UV irradiation,,by contrast with TiO_2 and mixture of TiO_2 with activated carbon respectively. The results shows TiO_2 were mainly consisted with global granules, whose diameters were from 30nm to 60nm in TiO_2/AC. TiO_2 granules are not reunited, containing Ti ,O ,C elements, and there are some C element diffused from the activated carbon carrier. Due to the reciprocity of activated carbon and TiO_2, and high concentration of Ti^(3+), TiO_2/AC showed high photocatalytic activity. The apparent degradation rate constant k was 0.0077?min^(-1) for Rhodamine B photodegradation, when TiO_2/AC contained 18±0.3% TiO_2, which were heated at 250?℃ for 2h in air and then heated at 500℃under a flow of nitrogen for 2?h.
出处
《环境科学学报》
CAS
CSCD
北大核心
2005年第7期918-924,共7页
Acta Scientiae Circumstantiae
基金
中国军事医学科学院国防预研项目~~
关键词
TiO2/活性炭
载体
光催化
罗丹明B
TiO_2 -coated activated carbon
carrier
photocatalysis
Rhodamine B
