采用第一原理方法,计算了Pb掺杂锐钛矿型TiO2的晶胞几何结构和电子结构,由于Pb的原子半径大于Ti,掺Pb后晶胞体积明显增大;水平方向和顶点方向的Pb-O键键长比相应的Ti-O键键长增长.由于Pb与O原子的sp轨道杂化作用,与Pb近邻的O原子p电子态出现尖锐的峰,并使处于第一价带的p电子态的带宽由4.6 ev增至7.3 ev;同时O的p轨道产生空态.掺杂后系统的导带底由Pb的p轨道构成.Pb掺杂使得锐钛矿型TiO2的能隙大幅度减小,因此,可以通过掺杂Pb实现对于锐钛矿型TiO2的能带调制,从而改变TiO2的光催化性能.计算结果与实验趋势相符.
参考文献
[1] | Fujishima A;Honda K .[J].Nature,1972,238:37. |
[2] | Brilmyer;George H;Fujishima et al.[J].Analytical Chemistry,1977,49(13):2057. |
[3] | Liu D;Kamat P V .[J].Physical Chemistry,1993,97(41):10 769. |
[4] | Fujii H;Ohtaki M et al.[J].Journal of Materials Science Letters,1997,16:1086. |
[5] | Alexander V;Vorontsov et al.[J].Journal of Photochemistry and Photobiology A:Chemistry,1999,125:113. |
[6] | Wang Tianmin;Wang Cong;Zheng ShuKai .[J].Advancement of Science,2001,13(03):360. |
[7] | Yu J G;Yu J C;Cheng B et al.[J].Journal of Sol-Gel Science and Technology,2002,24(01):39. |
[8] | Zhao X F;Meng X F;Zhang Z H et al.[J].Journal of Inorganic Materials,2004,19(01):140. |
[9] | Chen Qiang;Cao Honghong .[J].Journal of Molecular Structure(Theochem),2005,V723:135. |
[10] | Umebayashi T;Yamaki T et al.[J].Applied Physics Letters,2002,81(03):454. |
[11] | Kaxvinen S;Hirva P et al.[J].Journal of Molecular Structure(Theochem),2003,626:271. |
[12] | Valentin C D;Pacchioni G;Selloni A .[J].Physical Review B:Condensed Matter,2004,70:85 116. |
[13] | Okato T;Sakano T;Obara M .[J].Physical Review B:Condensed Matter,2005,72:115 124. |
[14] | Linsebigler A L;Lu G Q;Yates J T .[J].Chemical Reviews,1995,95(03):735. |
[15] | Marye A F;Dulary M T .[J].Chemical Reviews,1993,93:341. |
[16] | 郑树凯 .TiO<,2>半导体薄膜的光催化性能研究[D].北京航空航天大学,2003. |
[17] | Kresse G;Hafner J .[J].Physical Review B:Condensed Matter,1993,47:558. |
[18] | Kresse G;Furthmüller J .[J].Physical Review B:Condensed Matter,1996,54:11 169. |
[19] | Kresse G.;Joubert D. .From ultrasoft pseudopotentials to the projector augmented-wave method[J].Physical Review.B.Condensed Matter,1999(3):1758-1775. |
[20] | Chen Qiang,Cao Hong-Hong.Ab initio calculations of electronic structure of anatase TiO2[J].中国物理(英文版),2004(12):2121-2125. |
[21] | Kittel C.Introduction to Solid Physics[M].New York:John Wiley and Sons,Inc,1996 |
[22] | Burdett J K;Hughbanks T;Miller G J et al.[J].Journal of the American Chemical Society,1987,109:3639. |
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