偏振光作用下金红石型TiO2单晶(001)面的表面光电压谱研究

TiO2是一种优异的光电功能材料,被广泛用于有机污染物光降解及太阳能光电转换1～3].近年来的研究表明,表面原子排布对TiO2光电效能有决定性的影响.如Lowckamp3]的研究表明,TiO2的(101)晶面与其它晶面相比具有高的光化学还原Ag+的能力.本文结合偏振光技术与表面光电压谱技术对金红石型TiO2单晶(001)面的光伏响应特性进行了研究,通过对TiO2不同晶面的电子跃迁形式的区分及其对偏振光的不同响应,揭示了表面原子排布与TiO2光电性质之间的关系,实现了对材料功能特性的调控.

Studies of Surface Photovoltage Spectroscopy on the TiO2 Single Crystal(001) Surface

We used polarized surface photovoltage spectroscopy (PSPS) to study the photovoltage response of TiO\-2 single crystal (001) surface. Besides a band\|band transition at 355 nm and a indirect transition at 410 nm, we observed a new photovoltaic response at 380 nm in the PSPS spectrum which was assigned to the transition with relation to the surface state. Under different polarized directions, the intensity of photovoltaic responses at 380 nm and 410 nm changed regularly, which proved that the two transitions were interrelated to the atomic arrangement on the TiO\-2 single crystal (001) surface.