We describe the unusual properties of γ-SnSe, a new orthorhombic binary phase in the tin monoselenide system. This phase exhibits an ultranarrow band gap under standard pressure and temperature conditions, leading to high conductivity under ambient conditions. Density functional calculations identified the similarity and difference between the new γ-SnSe phase and the conventional α-SnSe based on the electron localization function. Very good agreement was obtained for the band gap width between the band structure calculations and the experiment, and insight provided for the mechanism of reduction in the band gap. The unique properties of this material may render it useful for applications such as thermal imaging devices and solar cells.
Bibliographical noteFunding Information:
The authors thank Dr. Sharon Hazan for expert assistance in FTIR spectrometery. D.A. is thankful for ISF Grant 576/21 and the support of the Azrieli college research fund. This work was supported by the Israel Science Foundation via Grant 1760/18 (Y.G.).
© 2023 American Chemical Society.
- electrical properties
- solution deposition
- thin films
- ultranarrow band gap