Dual-Gated WTe 2 /MoSe 2 van der Waals Tandem Solar Cells

Nicolas Cavassilas (1) , Demetrio Logoteta (1) , Youseung Lee , Fabienne Michelini (1) , Michel Lannoo (1) , Marc Bescond (2) , Mathieu Luisier (3)

1 IM2NP - Institut des Matériaux, de Microélectronique et des Nanosciences de Provence
2 L2MP - Laboratoire matériaux et microélectronique de Provence
3 ETH Zürich - Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich]

We propose and numerically investigate, through a multi-scale approach, a tandem solar cell based on a van der Waals heterostructure composed of two monolayers of transition metal dichalcogenides. The electronic connection between the two subcells is obtained via tunneling through the van der Waals heterojunction which is electrostatically controlled by means of a dual-gate. Furthermore, by adjusting the dual-gate voltages, the photocurrents in the two subcells can be matched and the tandem cell performances optimized. Assuming an optimal absorptance, as expected in light-trapping systems, we predict that a power conversion efficiency of 30.7%, largely exceeding that of the single subcells, can be achieved. The proposed design being suitable for other 1 van der Waals heterojunctions, this result shows that it represents a viable option for future high efficiency photovoltaic.

Domaines: Micro et nanotechnologies/Microélectronique

Nicolas Cavassilas, Demetrio Logoteta, Youseung Lee, Fabienne Michelini, Michel Lannoo, et al.. Dual-Gated WTe 2 /MoSe 2 van der Waals Tandem Solar Cells. Journal of Physical Chemistry C, 2018, 122 (50), pp.28545-28549. ⟨10.1021/acs.jpcc.8b09905⟩. ⟨hal-02331927⟩