A giant intrinsic photovoltaic effect in atomically thin ReS₂

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Photovoltaic (PV) effects in non-centrosymmetric materials can surpass the Shockley-Queisser limit.
• Two-dimensional (2D) materials offer potential for high-efficiency PV devices due to reduced dimensionality and bandgap.

Purpose of the Study:

• To investigate the giant intrinsic PV effect in atomically thin rhenium disulfide (ReS2) with broken centrosymmetry.
• To explore the potential of ReS2 as a material for advanced photovoltaic applications.

Main Methods:

• Fabrication of graphene/ReS2/graphene sandwich structures.
• Characterization of photovoltaic properties under visible light illumination.

Main Results:

• Observed significant short-circuit currents (Isc) in ReS2-based devices.
• Achieved the highest responsivity (110 mA W-1) and external quantum efficiency (25.7%) for PV effects in 2D materials.
• Attributed the giant PV effect to spontaneous polarization and a depolarization field in even-layered ReS2 flakes.

Conclusions:

• Atomically thin ReS2 exhibits a giant intrinsic photovoltaic effect.
• ReS2 is a promising candidate for developing high-efficiency, miniaturized photodetectors and solar cells.