Band structure engineering to improve the optical and thermoelectric properties of Rb2AgXBr6 (X=Al, In, Ga) for energy applications within DFT framework
Zunash Umar , Yasir Altaf , Fahim Ahmed , Najam Ul Hassan , Mushtaq Ali , Muhammad Zulfiqar , Farhan Yousaf
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引用次数: 0
Abstract
In the current study, we have employed density functional theory to evaluate thermoelectric, optical and electronic properties of rubidium bromide based double perovskites. It has been found that all three compounds i.e. Rb2AgAlBr6, Rb2AgGaBr6 and Rb2AgInBr6 have a direct band gap and the band gap appears at Γ symmetry point. The band gap of Rb2AgAlBr6 = 0.92 eV and of Rb2AgInBr6 = 0.29 eV whereas for Rb2AgGaBr6 has shown bands overlapping. The merged band gap of Ga-substituted material imparts in it excellent conductivity which makes it a potential candidate for application in conducting materials. Among all Rb2AgAlBr6 composition showed efficient TE properties with power factor of around 3.0 x 1011 W/msK2 and ZT value of 0.3. The optical properties found consist of high absorption coefficients (about 106 cm−1), low reflectivity (around 1–15 %), and high optical conductivity (approximately 1015sec−1).
期刊介绍:
The journal provides an international medium for the publication of theoretical and experimental studies and reviews related to the electronic, electrochemical, ionic, magnetic, optical, and biosensing properties of solid state materials in bulk, thin film and particulate forms. Papers dealing with synthesis, processing, characterization, structure, physical properties and computational aspects of nano-crystalline, crystalline, amorphous and glassy forms of ceramics, semiconductors, layered insertion compounds, low-dimensional compounds and systems, fast-ion conductors, polymers and dielectrics are viewed as suitable for publication. Articles focused on nano-structured aspects of these advanced solid-state materials will also be considered suitable.