Impact of alkaline-earth doping on electronic properties of the photovoltaic perovskite CsSnI: insights from a DFT perspective.

The oxidation of Sn(II) to the more stable Sn(IV) degrades the photovoltaic perovskite material CsSnI; however, this problem can be counteracted alkaline-earth (AE) doping. In this work, the electronic properties of CsSnAEI, with = 0 and 0.25, and AE = Mg and Ca, were investigated Density Functional Theory.

Effects of lithium on the electronic properties of porous Ge as anode material for batteries.

Recently, the need of improvement of energy storage has led to the development of Lithium batteries with porous materials as electrodes. Porous Germanium (pGe) has shown promise for the development of new generation Li-ion batteries due to its excellent electronic, and chemical properties, however, the effect of lithium in its properties has not been studied extensively. In this contribution, the effect of surface and interstitial Li on the electronic properties of pGe was studied using a first-principles density functional theory scheme.

Interstitial sodium and lithium doping effects on the electronic and mechanical properties of silicon nanowires: a DFT study.

In this work, we present a theoretical study of the electronic band structure and the Young's modulus of hydrogen-passivated silicon nanowires (H-SiNWs), grown along the [110] crystallographic direction, as a function of the concentration of interstitial sodium (Na) and lithium (Li) atoms. The study is performed using the supercell scheme and the density functional theory (DFT), within the local density approximation (LDA). The results show that the presence of Na or Li atoms closes the former semiconducting band gap of the H-SiNWs and shifts the Fermi energy into the conduction band.

Confinement effect on the low temperature specific heat for ultrathin silicon nanowires: a first principles study.

This work studied the phonon confinement effects at the low temperature specific heat of Si nanowires from first principles using density functional perturbation theory. The nanowires were modeled in the [0 0 1] direction for three different diameters, with the largest cross section being approximately 10 Å. The results indicate the specific heat can be described at low temperatures using a third-grade polynomial of the form c   =  λT  +  βT   +  γT, where the coefficients of quadratic and cubic terms are almost nonexistent for small diameters.

Lithium effect on the electronic properties of porous silicon for energy storage applications: a DFT study.

Theoretical studies on the effect of Li on the electronic properties of porous silicon are still scarce; these studies could help us in the development of Li-ion batteries of this material which overcomes some limitations that bulk silicon has. In this work, the effect of interstitial and surface Li on the electronic properties of porous Si is studied using the first-principles density functional theory approach and the generalised gradient approximation. The pores are modeled by removing columns of atoms of an otherwise perfect Si crystal, dangling bonds of all surfaces are passivated with H atoms, and then Li is inserted on interstitial positions on the pore wall and compared with the replacement of H atoms with Li.