Computational Approaches to Alkaline Anion-Exchange Membranes for Fuel Cell Applications.

Anion-exchange membranes (AEMs) are key components in relatively novel technologies such as alkaline exchange-based membrane fuel cells and AEM-based water electrolyzers. The application of AEMs in these processes is made possible in an alkaline environment, where hydroxide ions (OH) play the role of charge carriers in the presence of an electrocatalyst and an AEM acts as an electrical insulator blocking the transport of electrons, thereby preventing circuit break. Thus, a good AEM would allow the selective transport of OH while preventing fuel (e.

Thermal Expansion of 3C-SiC Obtained from In-Situ X-ray Diffraction at High Temperature and First-Principal Calculations.

In situ X-ray crystallography powder diffraction studies on beta silicon carbide (3C-SiC) in the temperature range 25-800 °C at the maximum peak (111) are reported. At 25 °C, it was found that the lattice parameter is 4.596 Å, and coefficient thermal expansion (CTE) is 2.

Janus transition metal dichalcogenides in combination with MoS for high-efficiency photovoltaic applications: a DFT study.

Exotic features of two-dimensional materials have been demonstrated, making them particularly appealing for both photocatalytic and photovoltaic applications. van der Waals corrected density functional theory calculations were performed on AAII-Se MoSSe, AAII-Te MoSTe, and AAII-Se WSSe heterostructures in this study. Our findings reveal that the heterostructures have high stability due to the tiny lattice mismatch and binding energy, which is extremely favorable for epitaxial growth of these heterostructures.

N-doped direction-dependent electronic and mechanical properties of single-walled carbon nanotube (SWCNT) from a first-principles density functional theory (DFT) and MD-simulation.

In this paper, the electronic and mechanical properties of Nitrogen (N) doped (6,1) single walled carbon nanotube (SWCNT) is analysed based on the first principles density functional theory (DFT) and Molecular dynamic (MD) calculation. A systematic N-doping on SWCNT was performed along zigzag (zz) and armchair (ac) direction, where the armchair doping is parallel to tube axis while zigzag is along the cross-section perpendicular to tube axis. The zz and ac doping resulted in variations in the electronic properties of the even and odd number of N-dopant atoms.

SnCmonolayer with transition metal adatom for gas sensing: a density functional theory studies.

The gas sensing properties of pristine SnCmonolayer and different transition metal adatom (TM-SnC, where TM = Fe, Co, Ni, Cu, Ru, Rh, Pd and Ag) was investigated using van der Waals corrected density functional theory. The understanding and potential of use of SnCmonolayers as sensors or adsorbent for CO, CO, NO, NOand SOgaseous molecules is evaluated by calculating the adsorption and desorption energetics. From the calculated adsorption energies, we found that the pristine SnCmonolayer and 3TM has desirable properties for removal of the considered molecules based on their high adsorption energy, however the 4TM is applicable as recoverable sensors.

Controlling the electronic and optical properties of HfS mono-layers lanthanide substitutional doping: a DFT+ study.

Two dimensional HfS is a material with potential applications in the field of photo-catalysis and advanced solid state devices. Density functional theory with the Hubbard parameter (DFT+) calculations were carried out to investigate the structural, electronic and optical properties of lanthanide dopant atoms (LN = La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) in the HfS mono-layer. The calculated electronic band gap for a pristine HfS mono-layer is 1.

Correction: Removal of fluoride ions using a polypyrrole magnetic nanocomposite influenced by a rotating magnetic field.

[This corrects the article DOI: 10.1039/C9RA07379E.].

Removal of fluoride ions using a polypyrrole magnetic nanocomposite influenced by a rotating magnetic field.

The impact of a varying rotating magnetic field in stimulating adsorption of fluoride ions onto a polypyrrole magnetic nanocomposite synthesized a polymerization process was evaluated. Under the effect of a rotating magnetic field, improved removal of adsorbate (10 mg L) from aqueous solution using the polypyrrole magnetic nanocomposite was observed, with a maximum removal of 78.2% observed at a magnetic field intensity of 0.

Influence of transition metal doping on the electronic and optical properties of ReS and ReSe monolayers.

We investigate the structural, electronic and optical properties of transition metal doped triclinic monolayered rhenium disulfide and diselenide (ReS and ReSe) by means of quantum mechanical calculations. The calculated electronic band gaps for ReS and ReSe monolayers are 1.43 eV and 1.

First principles LDA + U and GGA + U study of protactinium and protactinium oxides: dependence on the effective U parameter.

The electronic structure and properties of protactinium and its oxides (PaO and PaO2) have been studied within the framework of the local density approximation (LDA), the Perdew-Burke-Ernzerhof generalized gradient approximation [GGA(PBE)], LDA + U and GGA(PBE) + U implementations of density functional theory. The dependence of selected observables of these materials on the effective U parameter has been investigated in detail. The examined properties include lattice constants, bulk moduli, the effect of charge density distributions, the hybridization of the 5f orbital and the energy of formation for PaO and PaO2.

Silicene and transition metal based materials: prediction of a two-dimensional piezomagnet.

We use first-principles density functional theory based calculations to determine the stability and properties of silicene, a graphene-like structure made from silicon, and explore the possibilities of modifying its structure and properties through incorporation of transition metal ions (M: Ti, Nb, Ta, Cr, Mo and W) in its lattice, forming MSi(2). While pure silicene is stable in a distorted honeycomb lattice structure obtained by opposite out-of-plane displacements of the two Si sub-lattices, its electronic structure still exhibits linear dispersion with the Dirac conical feature similar to graphene. We show that incorporation of transition metal ions in its lattice results in a rich set of properties with a clear dependence on the structural changes, and that CrSi(2) forms a two-dimensional magnet exhibiting a strong piezomagnetic coupling.