First-principles discovery of stable, anisotropic, semiconducting Sb2X2O (X = S, Se) and Janus Sb2SSeO nanosheets for optoelectronics and photocatalysis

TL;DR

This study uses first-principles calculations to discover and analyze stable, anisotropic Sb2X2O monolayers and Janus Sb2SSeO nanosheets, highlighting their potential for optoelectronic and photocatalytic applications.

Contribution

It provides a comprehensive theoretical investigation into the stability, electronic, and optical properties of novel Sb-based 2D materials, including strain-tunable responses.

Findings

Confirmed thermodynamic and dynamical stability of the materials

Predicted bandgaps align with experimental data for Sb2S2O

Identified strong optical absorption and suitable band alignments for water splitting

Abstract

In this work, we conduct a comprehensive first-principles investigation into the design and discovery of novel antimony oxychalcogenide monolayers Sb2X2O (X = S, Se) and Janus Sb2SSeO, examining their structural stability, elastic, electronic, optoelectronic, and photocatalytic properties. Our analysis confirms their thermodynamic and dynamical stability and reveals low cleavage energies, indicating strong feasibility for mechanical exfoliation. The excellent agreement between our HSE06-predicted bandgap of bulk Sb2S2O and experimental measurements further validates the employed computational framework. EWe also find that their optoelectronic responses can be efficiently tuned via biaxial strain, providing a viable route for device-specific property engineering. Favorable band alignments, strong optical absorption, efficient carrier transport, and relatively high dielectric constants collectively support their candidacy for overall water splitting under neutral conditions.These results establish a solid theoretical foundation for the rational design of Sb-based 2D nanostructures and highlight their potential in next-generation direction-dependent optoelectronic and sustainable energy-conversion applications.