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DOE OSTI · 1827582

Exceptional Radiation Absorption in a Pentagon-Based Si Allotrope

Lopez-Bezanilla, Alejandro·Littlewood, Peter B.
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Abstract

Excellent photovoltaic performance is predicted in a pentagonal covalent network of Si in a hollow structure exhibiting both thermal and dynamical stability. Consisting of a combination of sp 2 and sp 3 hybridized Si atomic orbitals, the GW0 computed band structure shows an indirect band gap near the zone edge and also a manifold of directly absorbing transitions at frequencies in the window of visible light, in distinction with conventional Si. Hydrogenation of a single sp 2 site is predicted to lead to a robust local magnetic moment. In this study, we find a low formation energy at low pressure that is compatible with other experimentally known phases, suggesting that a stable phase might be obtained.

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Lopez-Bezanilla, Alejandro, Littlewood, Peter B.. 2021-05-11. Exceptional Radiation Absorption in a Pentagon-Based Si Allotrope. https://doi.org/10.1021/acs.nanolett.1c00549

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