摘要
以胶原纤维为模板分别负载钛(Ti4+)或钛(Ti4+)和镧(La3+),经高温煅烧制得介孔TiO2和La x/TiO2纳米纤维。通过场发射扫描电镜(FESEM)、N2吸附-脱附等温线、X射线衍射(XRD)、分子荧光光谱(PL)和紫外-可见吸收光谱(UV-Vis)等对这2类纳米纤维的结构和物理性能进行了表征。结果表明胶原纤维的纤维状结构能被较好地保留在TiO2和La x/TiO2纳米纤维中。TiO2和La x/TiO2纳米纤维的N2吸附-脱附等温线属于典型的Ⅳ型,表明其具有介孔结构。XRD分析表明,La3+的掺杂减小了TiO2的晶粒尺寸。与Degussa P25相比,介孔TiO2和La x/TiO2(x≤0.02)纳米纤维的紫外-可见吸收光谱红移,分子荧光光谱强度明显减弱。以孔雀石绿的光催化降解为模型反应,在可见光和紫外光激发下,介孔TiO2和La x/TiO2纳米纤维的光催化活性均高于Degussa P25。此外,La x/TiO2在可见光激发下的光催化活性高于未掺杂的TiO2纳米纤维。
Mesoporous TiO 2 and Lax/TiO 2 nano-fiber were prepared by loading titanium （Ti4＋ ）,or titanium （Ti4＋ ）and lanthanum （La3 ＋ ）on collagen fiber template,respectively,and then heat treated.The physico-chemical properties of these nano-fibers were fully characterized by means of field emission scanning electron microscopy （FESEM）,N2 adsorption-desorption,X-ray diffraction （XRD）,photoluminescence spectra （PL） and UV-Vis absorption spectra.It was found that the fibrous morphology of collagen fiber was well preserved in the TiO 2 and La0.02/TiO 2 nano-fibers.The N2 adsorption-desorption isotherms of TiO 2 and Lax/TiO 2 nano-fi-bers were the typical type Ⅳ,which associated with the characteristics of mesoporous materials.XRD analysis showed that La3 ＋ doped into TiO 2 has a significant influence on crystal size of TiO 2 .Compared with Degussa P25,the TiO 2 and Lax/TiO 2 （x ≤0.02）nano-fibers showed a red-shift in their UV-Vis absorption spectra,and their PL spectra intensity also exhibited a significant decrease.By using the photocatalytic degradation of mala-chite green （MG）as a model reaction,mesoporous TiO 2 and Lax/TiO 2 nano-fibers exhibited much higher pho-tocatalytic activities than Degussa P25 under visible light and UV light irradiation.In addition,Lax/TiO 2 nano-fibers showed remarkably improved visible light catalytic efficiency than that of un-doped TiO 2 nano-fibers.
出处
《功能材料》
EI
CAS
CSCD
北大核心
2014年第1期15-19,24,共6页
Journal of Functional Materials
基金
国家自然科学基金资助项目(20776090)
四川省教育厅面上资助项目(11ZB074)
四川师范大学大型精密贵重仪器设备开放共享专项基金资助项目(DJ2012-01)
