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Organic-Inorganic perovskites CsPbX 3 (X = Cl, Br, I) are investigated for their potential ability and use as solar cells and energy storage materials, using density function theory, generalized gradient approximation and modified Becke-Johnson (TB-mBJ) exchange potential. Structural analysis shows that the lattice constant and unit cell volume varies when CsPbX 3 (X = Cl, Br, I) change from cubic phase to tetragonal and orthorhombic structures. The electronic properties show that CsPbCl 3 , CsPbBr 3 and CsPbI 3 all are semiconductor in with bandgap between 0.79 eV and 2.54 eV. It is also observed that the bandgap changes when the structure changes. Optical properties show that these materials have a good absorption ability of photons due to their narrow bandgaps. The real ε 1 (ω) and imaginary ε 2 (ω) parts of their dielectric functions show that CsPbCl 3 , CsPbBr 3 and CsPbI 3 also possess a great ability of retaining the energy it absorbs. These properties make them very suitable for solar cells and energy storage applications. These materials also behave as superluminescent material at high photon energy. [ABSTRACT FROM AUTHOR]

In this paper we explore the electronic nature and thermoelectric properties of filled skutterudites AFe 4 Sb 12 (A Ca, Sr and Ba) by DFT and post-DFT techniques. The calculated results show that the filling of Ca, Sr, and Ba at the empty crystal sites enhances the thermoelectric performance of the host material. This increase is a consequence of the coupling between the guest and the host atoms, which affects the electronic density at different symmetry points that increases the density of states of the valence bands. The valence band edge is almost independent of the guest atoms, i.e., the s-bands of Ca, Sr and Ba have negligibly small contribution to the valence band edge. In these compounds, the maximum value of thermoelectric PF/τ of 42.43 × 10 14 μW/cmK 2 s and 33.57 × 10 14 μW/cmK 2 s for the n-type of SrFe 4 Sb 12 in the spin-up and down states respectively. The striking feature of these compounds is their effectiveness at the low chemical potential values for the best thermoelectric performance. [ABSTRACT FROM AUTHOR]