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arXiv · 1912.05186

In-situ monitoring of room temperature reactions of lanthanides with nitrogen and hydrogen at low pressures

Jay R. Chan·H. Joe Trodahl·Denis Lefebvre·Ben J. Ruck·Franck Natali
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Abstract

The dissociative chemisorption of molecular nitrogen on clean lanthanide surfaces at ambient temperature and low pressure is explored. In-situ conductance measurements track the conversion from the lanthanide metals to the insulating lanthanide nitrides. A small partial pressure of oxygen ($\sim 10^{-8}$ mbar) is shown to inhibit the nitridation of lanthanides at $10^{-4}$ mbar of N$_2$. The rate of nitridation as a function of nitrogen pressure is measured at low pressure for a series of lanthanide elements, gadolinium, terbium, dysprosium, ytterbium and praseodymium. Exposure of the lanthanide surfaces to both N$_2$ and H$_2$ results in the formation of NH$_3$.

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Jay R. Chan, H. Joe Trodahl, Denis Lefebvre, Ben J. Ruck, Franck Natali. 2019-12-11. In-situ monitoring of room temperature reactions of lanthanides with nitrogen and hydrogen at low pressures. https://arxiv.org/abs/1912.05186

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