First principle study of lead‐free double perovskites halidesRb₂Pd(Cl/Br)₆for solar cells and renewable energy devices: A quantumDFT

Abstract

Lead-free double perovskites are promising materials for environmental friendly photovoltaics and other optoelectronics. In this article, optical, thermoelectric, and thermodynamic properties of Rb 2 Pd(Cl/Br) 6 are explored by modified Becke and Johnson potential. The Goldschmidt tolerance factor (0.90-1.04) ensures the cubic phase is structurally stable. The negative formation energy and positive phonon dispersion authenticate the thermodynamic stability. The band gap of Rb 2 PdCl 6 is 1.88 eV, which reduces to 1.21 eV by replacing Cl with Br anion. The first absorption regions (620-413)nm for Rb 2 PdCl 6 and (826-496)nm for Rb 2 PdBr 6 increase their solar cells' implication. The transport properties are investigated by Boltzmann transport theory through the BoltzTraP code. Finally, the high values 0.76 and 0.75 of the figure of merit at room temperature also ensure their importance for thermoelectric generators. K E Y W O R D S figure of merits, modified Becke and Johnson potential, optoelectronic and solar cells, phonon dispersion, thermoelectric properties

Dielectric Behavior and Spontaneous Polarization as a Consequence of Berry Quantum Phase Effect: The case of La2NiMnO6 Double Perovskite—A New Approach to Polarization

“…A large number of materials especially double perovskites has been studied using various simulation packages based on first-principle calculations. [21][22][23][24][32][33][34][35] Firstprinciple studies declare La 2 NiMnO 6 as an indirect bandgap semiconductor and possessing a bandgap of about 1.4 eV. Full potential linearized augmented plane wave (FP-LAPW) method used in DFT showed ferromagnetic semiconducting behavior of LMNO.…”

“…Full potential linearized augmented plane wave (FP-LAPW) method used in DFT showed ferromagnetic semiconducting behavior of LMNO. [25][26][27][28][29][30][31][32][33][34][35][36] Various conduction mechanisms such as thermally activated conduction, [26][27][28][29][30][31][32][33][34][35][36][37] small polaron hopping, variable range hopping, [26] schnerkbergs polaronic conduction [28] explain the conduction mechanisms of the material. La 2 NiMnO 6 exists in two phases monoclinic and rhombohedral.…”

“…Syed also reported the existence of biphasic nature. [27][28][29][30][31][32][33][34][35][36][37][38] Biphasic nature has also been reported in case of LMNO nanoparticles. [28] The monoclinic phase usually exists at low temperatures while the rhombohedral phase occurs at higher temperatures.…”

“…of electronic devices and components like capacitors, FE random access memory (RAM), and are nowadays being used to explore a new type of device called as ferroelectric tunnel junction (FTJ) and show unique properties of modern interest such as giant electro-resistance effects. [28][29][30][31][32][33][34][35][36][37][38][39][40] One of the most studied FE materials is barium titanate (BaTiO 3 ), but the Rhombohedral phase of La 2 NiMnO 6 (LMNO) is also believed to exhibit the same property of FE behaviour.…”

First‐principles investigation of Rb2Ag(Ga/In)Br6 for thermoelectric and photovoltaic applications

“…In addition, they have excellent optoelectronic properties such as high optical absorption, appreciable optical conductivity, large dielectric constant, and long carrier lifetime. To date, many lead‐free double halide perovskites have been explored for energy applications [13–17]. But, most of them are either not stable or do not have suitable electronic and optical properties.…”