Thermal and dimensional stability of photocatalytic material ZnPS$_3$ under extreme environmental conditions

TL;DR

This study demonstrates that ZnPS$_3$ exhibits exceptional stability and tunable electronic properties under extreme pressure and cryogenic temperatures, making it suitable for sensing applications in harsh environments.

Contribution

It provides comprehensive experimental and theoretical analysis of ZnPS$_3$'s stability and phase transitions under extreme conditions, revealing its potential for extreme environment sensing.

Findings

Pressure-induced phase transition at 6.75 GPa

Stable across 15 to 100 GPa with a predicted semiconductor-to-semimetal transition at 100 GPa

High thermal expansion coefficient indicating sensitivity to temperature changes

Abstract

Zinc phosphorus trisulfide (ZnPS$_3$), a promising material for photocatalysis and energy storage, is shown in this study to exhibit remarkable stability under extreme conditions. We explore its optical and structural properties under high pressure and cryogenic temperatures using photoluminescence (PL) spectroscopy, Raman scattering, and density functional theory (DFT). Our results identify a pressure-induced phase transition starting at 6.75 GPa and stabilizing by 12.5 GPa, after which ZnPS$_3$ demonstrates robust stability across a broad pressure range of 15 to 100 GPa. DFT calculations predict a semiconductor-to-semimetal transition at 100 GPa, while PL measurements reveal defect-assisted emissions that quench under pressure due to enhanced non-radiative recombination. At cryogenic temperatures, PL quenching intensifies as non-radiative processes dominate, driven by a rising Gr\"uneisen parameter and reduced phonon population. Cryogenic X-ray diffraction (XRD) also reveals a high mean thermal expansion coefficient (TEC) of (4.369 $\pm$ 0.393) $\times$ 10$^{-5}$ K$^{-1}$, among the highest reported for 2D materials. This unique combination of tunable electronic properties under low pressure and high thermal sensitivity makes ZnPS$_3$ a strong candidate for sensing applications in extreme environments.