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arXiv · 1203.5669

Low-energy silicon allotropes with strong absorption in the visible for photovoltaic applications

Silvana Botti·José A. Flores-Livas·Maximilian Amsler·Stefan Goedecker·Miguel A. L. Marques
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Abstract

We present state-of-the-art first-principle calculations of the electronic and optical properties of silicon allotropes with interesting characteristics for applications in thin-film solar cells. These new phases consist of distorted sp$^3$ silicon networks and have a lower formation energy than other experimentally produced silicon phases. Some of these structures turned out to have quasi-direct and dipole-allowed band gaps in the range 0.8--1.5\,eV, and to display absorption coefficients comparable with those of chalcopyrites used in thin-film record solar cells.

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Silvana Botti, José A. Flores-Livas, Maximilian Amsler, Stefan Goedecker, Miguel A. L. Marques. 2012-03-26. Low-energy silicon allotropes with strong absorption in the visible for photovoltaic applications. https://doi.org/10.1103/physrevb.86.121204

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