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arXiv · 1506.06566

Exploring N-rich phases in LixNy clusters for hydrogen storage at nano-scale

Amrita Bhattacharya·Saswata Bhattacharya
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Abstract

We have performed cascade genetic algorithm and ab initio atomistic thermodynamics under the framework of first-principles density functional theory to study the (meta-)stability of a wide range of LixNy clusters. We found that hybrid xc-functional is essential to address this problem as a local/semi-local functional simply fails even to predict a qualitative prediction. Most importantly, we find that though in bulk Lithium Nitride, Li rich phase, i.e. Li3N, is the stable stoichiometry, in small LixNy clusters N-rich phases are more stable at thermodynamic equilibrium. We further show a that these N-rich clusters are promising hydrogen storage material because of their easy adsorption and desorption ability at respectively low (< 300K) and moderately high temperature (> 600K).

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Amrita Bhattacharya, Saswata Bhattacharya. 2015-06-22. Exploring N-rich phases in LixNy clusters for hydrogen storage at nano-scale. https://doi.org/10.1021/acs.jpclett.5b01435

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