A co-solvent, dimethylsulfoxide (DMSO), is added to the aqueous chemical "bath" deposition (CBD) process used to grow ZnOS buffer layers for thin film Cu2ZnSnSe4 (CZTSe) solar cells. Device performance improves markedly as fill factors increase from 0.17 to 0.51 upon the co-solvent addition. X-ray photoelectron spectroscopy (XPS) analyses are presented for quasi-in situ CZTSe/CBD-ZnOS interface...

The positions of electronic band edges are one important metric for determining a material's capability to function in a solar energy conversion device that produces fuels from sunlight. In particular, the position of the valence band maximum (conduction band minimum) must lie lower (higher) in energy than the oxidation (reduction) reaction free energy in order for these reactions to be thermod...

The structure and the electronic properties of single-walled zigzag BN and B3C2N3 nanotubes (n, 0; n=4–10) were investigated using first-principles calculations based on a density functional theory. A plane–wave basis set with periodic boundary conditions in conjunction with Vanderbilt ultrasoft pseudo-potential was employed. The energy gap of ZB3C<su...

Abstract: In this study, using density functional theory and the SIESTA computationalcode, we investigate the electronic and optical properties of the armchair graphenenanoribbons and the armchair boron nitride nanoribbons of width 25 in the presence of atransverse external electric field. We have observed that in the absence of the electricfield, these structures are se...

This research deals with heat and mass transfer in biscuit industrial baking ovens. In these ovens, heat reaches biscuits indirectly by radiation, convection and conduction. The method for numerical solution is that we first provide the related equations, then they are discretized by finite difference method (FDM), and finally, after encoding and writing a program for the computer, we run it. T...

The k·p method is known to be very efficient to accurately describe either the conduction band or the valence band or even both of them in the vicinity of a given point of the Brillouin zone. Recently multiband k·p Hamiltonians including up to 30 bands (and above), which allow us to calculate the band diagram of bulk materials for Td or Oh group semiconductors, have been proposed [1]. The strai...

The electronic structure of a large ~4096 atom! and realistic model of amorphous diamond is studied. The density of states and the individual eigenstates in the valence-band tail and midgap region are computed with two ‘‘order-N’’ spectral electronic-structure methods: the maximum entropy method and the shifted Lanczos method. We observe approximately exponential band tails at both valenceand c...

InxGa1± xP/GaAs (x ˆ 0.541 and 0.427) heterostructures, grown by Atomic Layer Molecular Beam Epitaxy (ALMBE) on low temperature substrates, have been characterised by pressure-dependent and time-resolved photoluminescence experiments. The excitonic optical transitions and recombination dynamics are both influenced by the particular band alignments of these systems. The valence band offset has b...