Piezo-phototronic solar cell based on 2D monochalcogenides materials

Piezo-phototronics is an emerging field which involves the coupling between photoexcitation, piezoelectricity, and semiconductor. The piezoelectric semiconductors have a non-centro symmetrical crystal structure. Piezo-phototronic effect can be applied to regulate the charge carriers' generation, separation, transport, and recombination by controlling the Schottky barrier height of Metal semiconductor contact or built-in potential of p-n junction. Recent studies have shown that Group IV Monochalcogenides have a higher piezoelectric constant in comparison with those predicted values in other two-dimensional (2D) materials. This work aims to investigate theoretically the material properties for piezo-phototronics. The performance of 2D piezo-phototronic solar cells has been studied using by monolayer group IV monochalcogenides: SnSe, SnS, GeSe, and GeS metal–semiconductor contact. The modulation ratio by piezoelectric charges has been investigated under applied external strains. The piezo-phototronic effect plays a key role on the enhancement of the performance in solar cell. This study opens a new window to produce high-efficiency solar cell based on the promising group IV monochalcogenides. (paper)