基于Si掺杂增强光吸收提升Li2SnO3 光催化降解四环素的研究

在Li₂SnO₃中掺杂Si，研究了Si掺杂Li₂SnO₃对四环素的光催化降解性能。结果表明，对Li₂SnO₃进行等电子Si掺杂使其光学吸收带隙减小和光吸收系数增大，提高了对四环素的光催化降解效率。等电子Si掺杂Li₂SnO₃为纯相不规则块状固体，随着Si掺杂量的增加其晶格参数呈减小的趋势。Si掺杂使样品的光催化性能显著提高。Si掺杂量为10%的样品，在紫外光照射25 min后光催化降解效率为75.8%，约为母体的2倍。Si掺杂Li₂SnO₃的光催化降解行为满足赝一级动力学模型，拟合速率常数为0.02464 min^-1。在Si掺杂Li₂SnO₃的价带顶形成的Si-O键减少了光学吸收带隙，使其光吸收能力增强。Si掺杂Li₂SnO₃的光催化降解机制，属于空穴主导型。

Photocatalytic Degradation of Tetracycline by Si Doped Li2SnO3

The photocatalytic degradation of tetracycline by Si-doped Li₂SnO₃ was investigated. The results show that, through iso-electron Si doping the optical absorption band gap of Li₂SnO₃ may be reduced, while its optical absorption coefficient is increased, in consequence, the photocatalytic degradation efficiency of the Si-doped Li₂SnO₃ for_{tetracycline is enhanced. The isoelectronicaly Si-doped Li2SnO3 is a pure and irregular mass solid, and its lattice parameters tend to decrease with the increase of Si doping amount. The photocatalytic performance of the Si-doped Li2SnO3 was significantly improved by Si doping. Under UV irradiation for 25 min, the photocatalytic degradation efficiency of tetracycline by the Si 10%-doped Li2SnO3 is 75.8%, which is about twice as that by the simple Li2SnO3. The photocatalytic degradation behavior of Si-doped Li2SnO3 conforms to the pseudo-first-order kinetic model, and the fitting rate constant is 0.02464 min^-1. The Si-O bond formed on the top of the valence band of Si-doped Li2SnO3 reduces the optical absorption band gap and enhances its optical absorption capacity. The photocatalytic degradation mechanism of Si-doped Li2SnO3 is cave-dominated.}