Highly efficient and stable lead-free cesium copper halide perovskites for optoelectronic applications: A DFT based study

Recently synthesized industrially significant perovskites Cs3Cu2X5 (X=Cl,Br,I) are subjected to a density functional theory (DFT) investigation utilizing the CASTEP code. This study explores various physical features, including structural, optical, thermodynamic, elastic, mechanical, and electronic properties. There is strong correlation between optimized structure parameters existing experimental data, which demonstrates reliability of our DFT-based computations. The band states (TDOS PDOS) analysis revealed that all studied direct gap semiconductors, Cs3Cu2Br5 has smallest (2.092 eV). We also discussed mechanical cell stability using Born criterion formation energy, respectively. dynamic each phase confirmed by elastic constants. According computed values Pugh's Poisson's ratios as well Cauchy's pressure, compounds ductile in nature. states, total charge density, Mulliken atomic populations reveal have complex bonding with both ionic covalent Finally, constant Debye temperatures Cs3Cu2Cl5, Cs3Cu2Br5, Cs3Cu2I5 been determined 82.90 K, 100.00 80.70 thermodynamics (relatively low ΘD Kmin) optical properties indicate investigated materials potential serve thermal barrier coating (TBC) materials.