Two-Dimensional BAs/InTe: A Promising Tandem Solar Cell with High Power Conversion Efficiency

Area of Science:

• Materials Science
• Renewable Energy
• Nanotechnology

Background:

• Tandem solar cells (SCs) offer potential for high efficiency by combining subcells with different absorption bands.
• Band gap mismatch between subcells remains a key challenge hindering performance improvement in tandem SC architectures.

Purpose of the Study:

• To design and investigate a novel two-dimensional (2D) BAs/InTe-based tandem solar cell (SC).
• To achieve a solar-to-electric conversion efficiency exceeding 30% by addressing band gap mismatch issues.

Main Methods:

• Density functional theory (DFT) calculations were used to assess the thermodynamic stability of hexagonal single-layer BX and single-layer YZ materials.
• HSE06 functional was employed to determine band gaps for constructing 2D tandem SCs.
• The BAs/InTe material combination was specifically chosen for its favorable band gap alignment.

Main Results:

• High thermodynamic stability was predicted for single-layer BX (X=P, As) and YZ (Y=Ga, In; Z=S, Se, Te) materials.
• The BAs/InTe-based tandem SC demonstrated a predicted power conversion efficiency of 30.2%.
• Experimental preparation of constituent materials like few-layer GaZ and InSe supports the feasibility of the proposed 2D tandem SCs.

Conclusions:

• The designed 2D BAs/InTe tandem SC effectively captures a broad solar spectrum, achieving high efficiency.
• The study highlights the potential of 2D materials for developing competitive, high-performance tandem solar cells.
• The findings suggest a promising pathway towards commercialized, efficient photovoltaic technologies.