Janus In2SeTe for photovoltaic device applications from first-principles study

In this work, we systematically investigate the electronic and optical properties of Janus In2SeTe and its potential applications on optoelectronic and photovoltaic devices through first-principles calculations. The Janus In2SeTe monolayer has a direct bandgap of 1.18 eV at the PBE level, a considerable ability to capture light in the visible-light region, and optical absorption coefficient up to 105 cm−1. It is found that the different electronegativity of the atoms on both sides of the In2SeTe monolayer, which indicates the structure possesses a vertical intrinsic electric field. Furthermore, we propose a solar cell structure with a few layers of stacked Janus In2SeTe and explore its photovoltaic performances. The photocurrent and power conversion efficiency of the In2SeTe solar cells are calculated. The results show that the photocurrent of In2SeTe solar cells can be comparable with thin-film silicon devices.