Density functional theory study of rutile VO2 surfaces
Density functional theory study of rutile VO2 surfaces
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DOI：
10.1063/1.4758319
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发表时间：
2012-10-21
影响因子：
4.4
通讯作者：
Grau-Crespo, Ricardo
中科院分区：
文献类型：
--
作者：
Mellan, Thomas A.;Grau-Crespo, Ricardo
我们提出的结果的密度泛函理论研究的金红石状二氧化钒，VO 2（R）的表面。计算了低米勒指数面的表面能，发现最稳定的表面取向是（110）面。VO 2（R）颗粒的平衡形态具有针状形状，横向由（110）面限制，顶部由（011）面限制。通过计算非化学计量组成的相对表面自由能作为氧化学势的函数，研究了（110）表面的氧化还原性质。据发现，VO 2（110）表面被氧化相对于化学计量组成，不仅在环境条件下，而且在更多的还原条件下，散装VO 2是稳定的，在与散装V2 O 5相比。吸附的氧形成表面氧钒物种比表面过氧物种更有利。(C)2012年美国物理学会。[http：//dx.doi.org/10.1063/1.4758319]
We present the results of a density functional theory investigation of the surfaces of rutile-like vanadium dioxide, VO2(R). We calculate the surface energies of low Miller index planes and find that the most stable surface orientation is the (110). The equilibrium morphology of a VO2(R) particle has an acicular shape, laterally confined by (110) planes and topped by (011) planes. The redox properties of the (110) surface are investigated by calculating the relative surface free energies of the non-stoichiometric compositions as a function of oxygen chemical potential. It is found that the VO2(110) surface is oxidized with respect to the stoichiometric composition, not only at ambient conditions but also at the more reducing conditions under which bulk VO2 is stable in comparison with bulk V2O5. The adsorbed oxygen forms surface vanadyl species much more favorably than surface peroxo species. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4758319]