Nanowire Structures for Energy Applications*

Recent studies on electronic, magnetic and optical properties of VO₂ (vanadium dioxide) material motivates to explore one-dimensional VO₂ nanowire. We have studied the structural and electronic, optical properties of monoclinic and rutile phase of VO₂ nanowire by performing first-principles calculations. The monoclinic phase showed semiconducting behaviour with a band gap of 1.17eV, while its bulk form showed a band gap of 0.7eV. The rutile phase behaves like as spin gapless semiconducting material. The rutile phase of VO₂ NW could find its applications in spintronic devices. We have also investigated the effect of SO₂, CO₂ and N₂ gas dopant on the monoclinic structure of VO₂ nanowire. The optical properties, density of states (DOS) have been investigated to understand the effect of dopant. It is clear from our results that the VO₂ monoclinic NW could likely to open up its application as an optical gas sensor.