Hydrogen activation on Anatase TiO2: Effect of surface termination

نویسندگان

چکیده

The mechanisms of H2 dissociation on three stoichiometric anatase TiO2 terminations, (001), (100) and (101), have been studied by means density functional theory (PBE+U) calculations. A two-step process was considered: first, into H+ H− pair, second the species migratetion to a neighboring O site, transferring electrons substrate. (001) termination shows lowest activation barriers for hydrogen dissociation, 0.37 eV, whereas highest value found 0.98 eV. For transfer from Ti near O, are higher (from 1.10 2.37 eV), which indicates step is kinetically more favorable than H process, although latter thermodynamically favorable. Electronic structure, vibrational frequency analysis as well temperature effects characterize reactivity. relationship between electronic geometry reactivity analyzed descriptors, results compared with ceria rutile facets.

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ژورنال

عنوان ژورنال: Catalysis Today

سال: 2022

ISSN: ['0920-5861', '1873-4308']

DOI: https://doi.org/10.1016/j.cattod.2021.11.020