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arXiv · 2005.00609

Thiophene-Tetrathia-Annulene monolayer (TTA-2D): A new 2D semiconductor material with indirect bandgap

Raphael M. Tromer·Leonardo D. Machado·Cristiano F. Woellner·Douglas S. Galvao
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Abstract

We propose a new 2D semiconductor material (TTA-2D) based on the molecular structure of Thiophene-Tetrathia-Annulene (TTA). The TTA-2D structural, electronic, and optical properties were investigated using \textit{ab initio} methods. Our results show that TTA-2D is a small indirect bandgap semiconductor ($0.6$ eV). A semiconductor-metal transition can be induced by applying a uniaxial strain. Our results also show that TTA-2D is thermally stable up to $T=1000$ K. TTA-2D absorbs in a large spectral range, from infrared to ultraviolet regions. Values of refractive index and reflectivity show that TTA-2D reflects only $10\%$ of the incident light in the visible region. These results suggest that TTA-2D is a promising material for solar cell applications.

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Raphael M. Tromer, Leonardo D. Machado, Cristiano F. Woellner, Douglas S. Galvao. 2020-05-01. Thiophene-Tetrathia-Annulene monolayer (TTA-2D): A new 2D semiconductor material with indirect bandgap. https://doi.org/10.1016/j.physe.2020.114586

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