Polymorphic Janus ZrSC monolayer: a first-principles study of structural, mechanical, vibrational, and electronic...

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Two-dimensional (2D) Janus materials possess asymmetric surfaces, enabling tailored electronic and mechanical characteristics.
• The hypothetical ZrSC monolayer combines carbide durability with chalcogenide electronic tunability.

Purpose of the Study:

• To systematically investigate the structural, mechanical, vibrational, and electronic properties of the ZrSC monolayer.
• To compare the two polymorphs: trigonal prismatic 1H and octahedral 1T.
• To assess the potential of ZrSC for next-generation electronic and spintronic devices.

Main Methods:

• First-principles density functional theory (DFT) calculations.
• Inclusion of van der Waals corrections and Hubbard-U adjustments.
• Analysis of cohesive energy, Young's modulus, bandgap, phonon spectra, and strain effects.

Main Results:

• The 1H ZrSC phase is the stable ground state with high cohesive energy and moderate Young's modulus.
• The 1H phase exhibits a tunable indirect bandgap of 1.63 eV, sensitive to mechanical strain.
• Phonon spectra confirm the dynamical stability of the 1H phase, while the 1T phase is metastable.
• Strain engineering induces semiconductor-to-semimetal transitions in the 1H phase.

Conclusions:

• The 1H ZrSC monolayer is a promising candidate for flexible electronics and spintronics.
• It offers a unique combination of mechanical robustness and electronic adaptability.
• Provides a foundation for experimental synthesis and device integration of this novel 2D material.