Tunable band alignment and large power conversion efficiency in a two-dimensional InS/ZnIn₂S₄ heterostructure

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Heterostructures modulate semiconductor bandgaps for improved optoelectronic device performance.
• Efficient photocarrier separation is crucial for high-performance devices.

Purpose of the Study:

• To design and investigate the electronic and photovoltaic properties of an InS/ZnIn2S4 van der Waals heterostructure.
• To explore methods for enhancing the power conversion efficiency (PCE) of the heterostructure.

Main Methods:

• First principles calculations were employed to study the electronic and photovoltaic properties.
• The effects of external electric fields and biaxial strain on band alignment and PCE were investigated.

Main Results:

• The InS/ZnIn2S4 heterostructure exhibits a reduced band gap (2.21 eV) and enhanced light absorption.
• A type-II1 band alignment was observed, leading to a PCE of 10.86%.
• External electric fields and biaxial strain significantly increased PCE to 12.19% and 20.80%, respectively.

Conclusions:

• The InS/ZnIn2S4 heterostructure shows promising potential for optoelectronic applications.
• External electric fields and strain are effective strategies to further enhance its optoelectronic device performance.