【作者】 刘亮亮； 黄晓伟； 付兴凯； 杜祖亮；

【Author】 Liangliang Liu;Xiaowei Huang;Xingkai Fu;Zuliang Du;Key Lab for Special Functional Materials of Ministry of Education,Henan Province,Henan University;

【机构】 河南大学特种功能材料教育部实验室；

【摘要】 由于TiO₂在不同环境和条件下都具有较高的稳定性,TiO₂广泛应用于各个技术领域,包括光催化剂、异相催化剂等。表面吸附的O₂分子可以用作电子的捕获剂来增强TiO₂的光催化活性。与此同时,氧还原反应对二氧化钛光催化反应速率起到重要的作用,氧还原反应与O₂分子的吸附能、解离能垒、和解离O原子的吸附能有关。因此,提高二氧化钛表面的氧还原反应会是一个非常有意义的工作。既然O₂分子很难在干净的TiO₂表面吸附,那么研究带有缺陷的表面系统与O₂分子的相互作用是一个有趣的话题。本研究通过第一性计算表面H原子、亚表面Ti间隙与TiO₂表面O₂分子之间的相互作用,结果表明这些缺陷有利于O2分子的吸附,同时能够大大降低O₂分子解离的能垒,使TiO₂表面产生更多的活性O原子,进而增强TiO2表面的氧化活性。更多还原

【Abstract】 Because of its abundance and high stability in different environments,TiO₂ is widely used in photocatalysis and heterogeneous catalyst.Surface O₂ can be used as electron scavengers to enhance the photocatalytic activity,meanwhile,the oxygen reduction reaction（ORR）plays a critical role in photocatalysis,and the ORR strongly depends on the O₂ adsorption and dissociation,so it is interesting to study the adsorption and dissociation of O₂ molecules on the surface.Since the O₂ adsorption on a clean TiO₂ surface is hard to happen,effect of surface H atoms and Ti interstitial on O₂ adsorption and dissociation is calculated with first principles in this study.The results show that surface H atoms or subsurface Ti interstitial could significantly enhance O₂adsorption and reduce the energy barrier of O₂ dissociation,producing more active O atoms on Ti O₂ surface,which would improve oxidation activity of TiO₂ surface.更多还原