COMPUTATIONAL INVESTIGATIONS INTO THE PHYSICAL PROPERTIES OF CHALCOGENIDE PEROVSKITES MgBS 3 (B = Hf,Ti, and Zr) FOR PHOTOVOLTAIC APPLICATIONS: DFT INSIGHT

A promising class of materials, chalcogenide perovskites (CPs), are characterized by their exceptional stability, environmentally friendly composition, and intriguing optoelectronic properties. To comprehensively analyze the structural, mechanical, and thermodynamic characteristics of MgBS 3 (where B = Hf, Ti, and Zr), one of the most promising members of the metal chalcogenide perovskite family, we employed density functional theory (DFT) simulations. Our theoretical results indicate that MgHfS 3 is the most stable compound, aligning well with the reported syntheses of other chalcogenide perovskites. These materials exhibit anisotropy, robust mechanical stability, and significant resistance to deformation under external stress, fulfilling the Born stability criteria. Pugh ratio analysis confirms that MgZrS 3 (1.99) is ductile, as well as MgHfS 3 (1.91) while MgTiS 3 (0.05) is brittle. Thermodynamic calculations reveal the Debye temperatures of MgHfS 3 (282.94 K), MgZrS 3 (325.67 K), and MgTiS 3 (376.76 K), along with vibrational energies, entropies, and constant volume heat capacities of MgHfS 3 (115 JK⁻¹Nmol⁻¹) and MgZrS 3 (112 JK⁻¹Nmol⁻¹). Notably, the free vibrational energy decreases rapidly with increasing temperature. These characteristics underscore the potential of MgBS 3 -based CPs in developing more robust and efficient optoelectronic devices and indoor photovoltaics. Furthermore, due to its lower Debye temperature compared to other CPs, MgHfS 3 emerges as a significant candidate for thermodynamic applications. Our findings suggest that MgBS 3 chalcogenide perovskites (B = Hf, Ti, and Zr) possess substantial promise for advancing ferromagnetic materials, renewable energy solutions, and optoelectronic devices.