Alkali metal substitutional effect on the structural, mechanical, optoelectronic and transport properties of X2LaCuCl6 double perovskites

Uloženo v:
Podrobná bibliografie
Název: Alkali metal substitutional effect on the structural, mechanical, optoelectronic and transport properties of X2LaCuCl6 double perovskites
Autoři: Muhammad Awais Jehangir, Rajwali Khan, Nabeel Israr, Atif Mossad Ali, Aijaz Rasool Choudhary, G. Murtaza
Zdroj: Scientific Reports, Vol 15, Iss 1, Pp 1-20 (2025)
Informace o vydavateli: Nature Portfolio, 2025.
Rok vydání: 2025
Sbírka: LCC:Medicine
LCC:Science
Témata: Solar cells, Tolerance factor, Density of states (DOS), Band structure plots, Photovoltaics, Transport properties, Medicine, Science
Popis: Abstract Double perovskites have attracted significant interest as promising candidates for energy harvesting applications and as potential alternatives to lead-based organic solar cells. In this study, we investigate the structural, mechanical, electronic, optical, and transport properties of X₂LaCuCl₆ (X = K, Rb, Cs) using first-principles calculations within the framework of the full-potential linearized augmented plane wave (FP-LAPW) method as implemented in WIEN2k. Structural parameters optimized using the Birch–Murnaghan equation of state show a systematic increase in lattice constants and a corresponding decrease in bulk modulus with increasing ionic radius of the alkali metal (X = K, Rb, Cs) cation. The thermodynamic and dynamic stability of the compounds is confirmed through formation energy, cohesive energy calculations, Goldschmidt tolerance factors, and phonon dispersion analyses using the Phonopy package with ultrasoft pseudopotentials in Quantum ESPRESSO. Elastic constants satisfy the mechanical stability criteria, and derived mechanical parameters indicate ductile behaviour. Electronic band structures obtained via the modified Becke–Johnson (mBJ) potential reveal indirect band gaps of 1.83 eV (K), 1.81 eV (Rb), and 1.40 eV (Cs). Optical absorption spectra exhibit strong peaks in the far-ultraviolet region 112.41 cm⁻¹ at 11.41 eV (K), 118.56 cm⁻¹ at 11.36 eV (Rb), and 116.74 cm⁻¹ at 10.19 eV (Cs) with corresponding minimum reflectivity values of 19% for K and Rb compounds, and 22% for Cs, suggesting suitability for high-frequency optoelectronic applications. Transport properties, analysed using the BoltzTraP code, reveal Seebeck coefficients of 81.6 µV/K (K), 82.2 µV/K (Rb), and 66.7 µV/K (Cs), with dimensionless thermoelectric figure-of-merit (ZT) values of 0.17, 0.33, and 0.18, respectively. These findings suggest that X₂LaCuCl₆ compounds exhibit a favourable combination of optoelectronic and thermoelectric properties, making them promising candidates for integration into ultraviolet photonic and energy conversion devices.
Druh dokumentu: article
Popis souboru: electronic resource
Jazyk: English
ISSN: 2045-2322
Relation: https://doaj.org/toc/2045-2322
DOI: 10.1038/s41598-025-20948-0
Přístupová URL adresa: https://doaj.org/article/c22318682f6a4217a8f546894a9ee486
Přístupové číslo: edsdoj.22318682f6a4217a8f546894a9ee486
Databáze: Directory of Open Access Journals
Popis
Abstrakt:Abstract Double perovskites have attracted significant interest as promising candidates for energy harvesting applications and as potential alternatives to lead-based organic solar cells. In this study, we investigate the structural, mechanical, electronic, optical, and transport properties of X₂LaCuCl₆ (X = K, Rb, Cs) using first-principles calculations within the framework of the full-potential linearized augmented plane wave (FP-LAPW) method as implemented in WIEN2k. Structural parameters optimized using the Birch–Murnaghan equation of state show a systematic increase in lattice constants and a corresponding decrease in bulk modulus with increasing ionic radius of the alkali metal (X = K, Rb, Cs) cation. The thermodynamic and dynamic stability of the compounds is confirmed through formation energy, cohesive energy calculations, Goldschmidt tolerance factors, and phonon dispersion analyses using the Phonopy package with ultrasoft pseudopotentials in Quantum ESPRESSO. Elastic constants satisfy the mechanical stability criteria, and derived mechanical parameters indicate ductile behaviour. Electronic band structures obtained via the modified Becke–Johnson (mBJ) potential reveal indirect band gaps of 1.83 eV (K), 1.81 eV (Rb), and 1.40 eV (Cs). Optical absorption spectra exhibit strong peaks in the far-ultraviolet region 112.41 cm⁻¹ at 11.41 eV (K), 118.56 cm⁻¹ at 11.36 eV (Rb), and 116.74 cm⁻¹ at 10.19 eV (Cs) with corresponding minimum reflectivity values of 19% for K and Rb compounds, and 22% for Cs, suggesting suitability for high-frequency optoelectronic applications. Transport properties, analysed using the BoltzTraP code, reveal Seebeck coefficients of 81.6 µV/K (K), 82.2 µV/K (Rb), and 66.7 µV/K (Cs), with dimensionless thermoelectric figure-of-merit (ZT) values of 0.17, 0.33, and 0.18, respectively. These findings suggest that X₂LaCuCl₆ compounds exhibit a favourable combination of optoelectronic and thermoelectric properties, making them promising candidates for integration into ultraviolet photonic and energy conversion devices.
ISSN:20452322
DOI:10.1038/s41598-025-20948-0