Year: 2024
Type: preprint
Abstract: Chalcogenide perovskites are lead-free materials for potential photovoltaic or thermoelectric applications. BaZrS$_3$ is the most studied member of this family due to its superior thermal and chemical stability, desirable optoelectronic properties, and low thermal conductivity. Phase transitions of BaZrS$_3$ remain underexplored in the literature, as most experimental characterizations of this material have been performed at ambient conditions where the orthorhombic Pnma phase is reported to be stable. In this work, we study the dynamics of BaZrS$_3$ across a range of temperatures and pressures using an accurate machine-learning interatomic potential trained with data from hybrid density functional theory calculations. At 0 Pa, we find a first-order phase transition from the orthorhombic to tetragonal I4/mcm phase at 610 K, and a second-order transition from the tetragonal to the cubic Pm-3m phase at 880 K. The tetragonal phase is stable over a larger temperature range at higher pressures. To confirm the validity of our model we compare our results with a range of published experimental data and report a prediction for the X-ray diffraction pattern as a function of temperature.
Source: arXiv (Cornell University)
Institutions: Northumbria University, Chalmers University of Technology
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
Awards: G1135830669, G243872479, The Materials and Molecular Modelling Hub, G417250887, EPSRC Centre for Doctoral Training in Renewable Energy Northeast Universities (ReNU), Phase behavior and electronic properties of mixed halide perovskites from atomic scale simulations, Hydrogen trapping by carbides in steel, G6539064727, Tier 2 Hub in Materials and Molecular Modelling, Introducing heterogeneous HPC solutions to UK's MMM community, NAISS, G8997374688, G90098195
OpenAlex ID: W4404652945