Hydrothermal Synthesis and Comprehensive DFT Evaluation of Ba2PrMnO6 Double Perovskite Nanocrystals for Next-Generation Spintronic and Optoelectronic Technologies

Abstract

In the context of today's research priorities, where the demand for multifunctional and eco-friendly materials is rapidly increasing, lead-free double perovskites are emerging as a significant development in the arena. This study presents the synthesis of Ba2PrMnO6 (BPMO) double perovskite nanocrystals for the first time via a hydrothermal method, and a comprehensive evaluation has been conducted using the density functional theory (DFT) framework. Structural, thermodynamic, electronic, optical, and mechanical properties were investigated through X-ray diffraction (XRD), Ultraviolet-visible (UV-Vis) spectrophotometer, FESEM/EDX, FTIR, and density functional theory (DFT) calculations. XRD confirms a stable tetragonal I4/m phase with experimental lattice constants in excellent agreement with theory. UV-Vis analysis reveals a semiconducting nature with a bandgap of 1.98 eV, consistent with DFT calculations, whereas electronic structure calculations show a combination of metallic and semiconducting behavior across spin channels. FESEM reveals nanoscale grains with an average particle size of ~58 nm, while EDX confirms the elemental composition, purity and uniformity. FTIR identifies the presence of PrO6 and MnO6 octahedra in the sample. Optical spectra, dielectric response, and absorption features indicate the presence of strong orbital hybridization effects. Mechanical and thermodynamic stability demonstrate stable elastic behavior, phonon integrity, and predictable thermal trends, confirming the robustness of BPMO over a wide temperature range. A strong correlation between the lattice parameters, structural distortion, octahedral tilting, spin-polarized bandgap, and optical response underscores the potential of BPMO as a promising candidate for next-generation spintronic and optoelectronic applications.