【摘要】 利用基于密度泛函理论的第一性原理研究了I掺杂金红石Ti O2(110)表面的形成能和电子结构,分析了不同掺杂位置的结构对Ti O2光催化性能的影响.计算表明,氧化环境下I最容易替代掺杂表面五配位的Ti,而还原环境下最容易替代掺杂表面的桥位氧.I替位Ti或I替位O都能降低禁带宽度,可能使Ti O2吸收带出现红移现象或产生在可见光区的吸收,其中I替位桥位氧的禁带宽度最小.吸收光谱表明,I掺杂不仅能提高Ti O2可见光响应,同时可增加紫外光的吸收能量,提高其可见光及紫外光下的光催化性能.更多还原

【Abstract】 The formation energy and electronic structure of iodine(I)-doped rutile Ti O2(110) surface are investigated using the first-principles method based on the density functional theory. The results indicate that I prefers to replace the five-coordinated Ti in the oxidation environment and the bridging O could be replaced by I preferentially in the reducing environment. Whether I replaces O or Ti can reduce the band gap and cause the red shift of the absorption band edge or produce the absorption in the visible light. The band gap narrows most obviously when I replaces the bridging O. The absorption spectrum shows that I doping could not only improve its visible light response but also enhance its absorption peak of UV-light, leading to the improvement in photocatalytic performance under visible and UV light.更多还原