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arXiv · 1505.08074

An in- and ex-situ TEM study into the oxidisation of titanium (IV) sulphide

Edmund Long·Sean O'Brien·Edward A. Lewis·Eric Prestat·Clive Downing·Clotilde S. Cucinotta·Stefano Sanvito·Sarah J. Haigh·Valeria Nicolosi
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Abstract

The degradation of liquid dispersed titanium (IV) sulphide (TiS$_2$) is studied from the point of view of oxidisation. TiS$_2$ is a layered two-dimensional nanomaterial, with potential for energy storage applications. However, flakes in dispersion were observed to degrade. We examined two oxidisation routes: deionised water at room temperature and oxygen gas within the temperature range 150-350°C. Water was seen to slowly oxidise flakes inwards from the edge, forming an amorphous oxide, a result comparable to the state of flakes which degraded within the original dispersion. Oxygen gas was seen to rapidly oxidise entire flakes to a polycrystalline oxide, when heated 275 °C and above. Degradation was studied with scanning transmission electron microscopy (STEM), energy dispersed x-ray spectroscopy (EDX) and electron energy-loss spectroscopy (EELS). Density Functional Theory calculations have shown oxidisation by both water and gas molecules to be thermodynamically favourable.

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Edmund Long, Sean O'Brien, Edward A. Lewis, Eric Prestat, Clive Downing, Clotilde S. Cucinotta, Stefano Sanvito, Sarah J. Haigh, Valeria Nicolosi. 2015-05-29. An in- and ex-situ TEM study into the oxidisation of titanium (IV) sulphide. https://arxiv.org/abs/1505.08074

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