Nonadiabatic molecular dynamics investigation on charge separation in rutile TiO2/h-BN interfaces

Abstract

In various experimental studies, h-BN/TiO2 heterostructure greatly improves the photocatalytic capacity of TiO2. However, the actual influence of h-BN is unclear. In this work, by performing ab initio nonadiabatic molecular dynamics (NAMD) calculation, we studied the h-BN/TiO2[rutile (110)] heterostructure and found h-BN owns a strong attracting ability of the hole which makes the hole to get out of the atomic oscillation inside TiO2 in a short time (250 fs). By comparing the NAMD result of the intrinsic TiO2 (110) surface, the actual enhancement of the photocatalytic ability is found to be provided by the carrier separation h-BN brings due to the introduction of h-BN will accelerate the hole relaxation. This finding clearly illustrates the role of h-BN in the photocatalysis process in the h-BN/TiO2 heterostructure, thus better control of the TiO2 photocatalytic ability may be conducted.