硼族元素掺杂对K_2La_2Ti_3O_(10)光催化产氢性能的影响  

Photocatalytic Activity of K_2La_2Ti_3O_(10)Doped with Boron Family Elements

作　　者：杨亚辉[1,2] 陈启元[1] 李洁[1] 尹周澜[1] 

机构地区：[1]中南大学化学化工学院,长沙410083 [2]中南大学资源加工与生物工程学院,长沙410083

出　　处：《无机化学学报》2009年第2期256-263,共8页Chinese Journal of Inorganic Chemistry

基　　金：国家"863"计划项目(No.2002AA327140);湖南省自然科学基金项目(No.08JJ3022);湖南省科技计划项目(No.08FJ4105)资助

摘　　要：通过溶胶-凝胶法制备了层状钙钛矿结构的K2La2Ti3O10及硼族元素掺杂的K2La2Ti3O10,采用X-射线衍射(XRD)、紫外可见漫反射光谱(DRS)等对K2La2Ti3O10及硼族元素掺杂K2La2Ti3O10进行表征。以I-为电子给体、分别在紫外和可见光辐射下研究了K2La2Ti3O10及硼族元素掺杂K2La2Ti3O10光催化分解水的产氢活性;采用第一性原理,计算了硼族元素掺杂对K2La2Ti3O10半导体能带结构和态密度的影响,从电子结构的变化揭示了掺杂引起光催化活性差异的原因。研究结果表明,硼族元素的掺入能够改善和提高K2La2Ti3O10的光解水产氢活性;在B,Al,Ga,In与Ti的物质的量的比为0.01∶1的情况下,K2La2Ti3O10紫外光催化分解水产氢速率分别为151.7、119.6、155和119.2μmol.L-1.h-1,比K2La2Ti3O10掺杂改性前产氢速率分别提高了166%、110%、172%和109%,可见光分解水的产氢速率为67.0、60.5、55.0和50.0μmol.L-1.h-1,分别为K2La2Ti3O10掺杂改性前产氢速率的4、3.7、3.3和3倍。The layered perovskite type oxide, K2La2Ti3O10 and K2La2Ti3O10 doped with boron family elements were prepared by sol-gel method and were characterized by power X-ray diffraction, UV-Vis diffuse reflectance spectroscopy. The photocatalytic activity for water splitting of K2La2Ti3O10 and K2La2Ti3O10 doped with boron family elements were investigated with I- as electron donor under ultraviolet and visible light irradiation respectively. The electronic structure of K2La2Ti3O10 doped with boron family elements has been analyzed by the first principle calculations, which reveals the photo responses in the visible region and the improvement of the photocatalytic activity of K2La2Ti3O10.Conclusions were made that K2La2Ti3O10 doped with boron family elements exhibited higher photocatalytic reactivity of hydrogen production. When the doping concentration of （B, Al, Ga, In）：Ti was 0.01：1, the ultraviolet hydrogen production rate were 151.7, 119.6, 155 and 119.2 μmol.L^-1.h^-1 which were raised by 166%, 110%, 172% and 109% compared with undoped K2La2Ti3O10 respectively, the visible hydrogen production rate were 67.0, 60.5, 55.0 and 50.0 μmol.L^-1.h^-1 which were 4, 3.7, 3.3 and 3 times those with undoped K2La2Ti3O10 respectively.

关 键 词：K2LA2TI3O10 光催化活性 氢气 第一性原理 

分 类 号：O643.32[理学—物理化学]