Open AccessTheoretical study of native point defects on anatase TiO2 (101) surface
Author(s) -
Xinguo Ma,
Jiang Jian-jun,
Pei Liang
Publication year - 2008
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.57.3120
Subject(s) - pseudopotential , vacancy defect , anatase , crystallographic defect , materials science , lattice (music) , atom (system on chip) , crystal structure , interstitial defect , condensed matter physics , chemical physics , crystallography , molecular physics , physics , chemistry , doping , biochemistry , optoelectronics , photocatalysis , computer science , acoustics , embedded system , catalysis
First-principles plane-wave pseudopotential calculations were performed to study the energetics and the geometical structures of intrinsic vacancies and interstitials on the anatase TiO2 (101) crystal surface. Firstlywe analyzed the effects of point defects on the geometrical structures. For the O vacancyall the nearest-neighbor Ti atoms move away from the vacancy toward the other O neighborhood. As Ti1 or Ti2 is missing hereO1 atom spontaneously and strongly binds with nearest-neighbor O on the lattice site to form an O2 molecule. The results also show that interstitial Tii2 affects little host lattice and the interstitial Oi would spontaneously bind to lattice oxygen. By investigating the calculated defect formation energieswe found that under the O-rich conditionthe VTi1 and Oi formation are favorablehoweverunder the Ti-rich conditionalthough the point defects of Tii2 and VO1 easily appearthe formation energy of the Tii2 is lower than that of the VO1. Finallyto determine the relative stability of the point defectsthe formation enthalpies of several point defects were considered.