A periodic density functional theory investigation of tetrazole derivatives adsorbed on anatase TiO2 surface applied in dye-sensitized solar cell

摘要

In the current investigation, four different additives namely 2H-tetrazole (2HTz), 2H-tetrazole-5-amine (5ATz), 2H-tetrazole-5-thiol (5TTz) and 4-tert-butylpyridine (TBP) are utilized to examine the interaction of these additives with anatase TiO2 (101), (100) and (001) surfaces under vacuum condition. In addition, analyses of adsorption mode and electronic structure using a periodic density functional theory method is performed to find the interaction of acetonitrile solvent. The obtained results revealed that these four additives are adsorbed into the sorbent surface as the following order of (100) < (101) < (001). The interesting observed point is that the bonding experience a great influence due to the defects appeared in the upmost TiO2 (001) surface induced by additive adsorption. Finally, the modeling revealed that a positive Fermi energy shift order is as follow: (001) < (100) < (101) for all of the examined additives which may lead to higher open-circuit photovoltage of dye-sensitized solar cells. Besides, the obtained results demonstrated that although addition of the acetonitrile solvent leads to a reduction in adsorption energy, it improves the shift trend of Fermi energy except for 2HTz and 5TTz-TiO2 (001) systems. (C) 2017 Elsevier B.V. All rights reserved.