Characterization of Planar Defect in Layered Perovskite Photocatalyst Y$_2$Ti$_2$O$_5$S$_2$ by Electron Microscopy and First-Principles Calculations
Characterization of Planar Defect in Layered Perovskite Photocatalyst Y$_2$Ti$_2$O$_5$S$_2$ by Electron Microscopy and First-Principles Calculations
复制标题
通过电子显微镜和第一原理计算表征层状钙钛矿光催化剂 Y$_2$Ti$_2$O$_5$S$_2$ 中的平面缺陷
DOI：
10.1021/acs.jpcc.3c00820
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发表时间：
2023
影响因子：
3.7
通讯作者：
and Seiichiro L. Ten-no
中科院分区：
文献类型：
--
作者：
Mamiko Nakabayashi;Kazutaka Nishiguchi;Xizhuang Liang;Takashi Hisatomi;Tsuyoshi Takata;Takashi Tsuchimochi;Naoya Shibata;Kazunari Domen;and Seiichiro L. Ten-no
层状钙钛矿结构的Y2 Ti 2 O 5S 2是一种很有前途的半导体光催化剂，其电子结构适合于在可见光下进行全水分解。然而，与其他光催化剂类似，合成过程中的结构缺陷应得到控制。透射电子显微镜（TEM）观察发现，助熔剂法合成的Y2 Ti 2 O 5S 2中存在由S-Mg-S层组成的极大的平面缺陷。利用基于密度泛函理论的第一性原理计算确定了平面缺陷结构和电子结构。的形成能量的评价表明，S和Mg-穷人的条件下，可以防止缺陷的形成。此外，我们还讨论了平面缺陷引起的杂质能级及其对电子态和催化性能的影响。
Layered perovskite Y2Ti2O5S2is a promising semiconductor photocatalyst with an electronic structure suitable for overall water splitting under visible light. However, similar to other photocatalysts, structural defects during synthesis should be controlled. Transmission electron microscopy (TEM) revealed extremely large planar defects composed of S–Mg–S layers in Y2Ti2O5S2synthesized using the flux method. We determined the planar defect structure and electronic structure using first-principles calculations based on the density functional theory. The evaluation of the formation energy suggests that S- and Mg-poor conditions may prevent defect formation. Furthermore, we discuss the impurity levels caused by the planar defects and their effects on the electronic state and catalytic performance.