Tungsten oxide nanowire on copper surfaces: a DFT model

R. SEDIVÁ; K. MASEK; M. E. PRONSATO; C. PISTONESI

RSC Advances

Royal Society of Chemistry

Año: 2016 vol. 6 p. 88463 - 88468

We studied a model of a one dimensional tungsten oxide nanowire on reconstructed Cu(110) surfaceby Density Functional Theory calculations. The effect of oxygen vacancies on the electronicstructure was analyzed (DOS). Nanowire equilibrium geometric configuration corresponds totungsten oxide strips oriented along Cu [1-10] direction, in which W-W distances are similar to thebulk data, in agreement with electron diffraction experiments. Bader charge analysis shows thatelectron charge of W atoms corresponds to a tungsten atom in 6+ oxidation state. The presence of theoxygen vacancies increase the electronic charge of tungsten atoms. Formation of the oxygenvacancies by removal of terminal oxygen atoms is energetically favorable. Calculated PDOS showsstabilization of tungsten states to lower energies due to the presence of oxygen vacancies.