Mechanisms of Phase Evolution in the Cu-Sb-S System Controlled by the Incorporation of Cu in SbS Thin Films.

Ongoing research in metal chalcogenide semiconductors aims to develop alternative materials for optoelectronic devices. However, due to cost and environmental considerations, there is an increasing emphasis on utilizing green materials. This shift toward sustainable materials and processing is expected to become essential in materials research.

The role of organic cations as additives in photovoltaic perovskites.

The design of additives for perovskite-based solar cells seeks to improve the balance between stability and power conversion efficiency. Organic molecules such as theophylline, theobromine and caffeine (xanthines) have proved to be a good engineering solution. As an alternative, we present a first-principles study of the use of organic cations as additives.

Enhancing the stability and efficiency of MAPbI perovskite solar cells by theophylline-BF alkaloid derivatives, a theoretical-experimental approach.

Perovskite solar cells (PSCs) are an evolving photovoltaic field with the potential to disrupt the established silicon solar cell market. However, the presence of many transport barriers and defect trap states at the interfaces and grain boundaries has negative effects on PSCs; it decreases their efficiency and stability. The purpose of this work was to investigate the effects on efficiency and stability achieved by quaternary theophylline additives in MAPbI PSCs with the structure FTO/TiO/perovskite/spiro-OMeTAD/Ag.

Comment on "Investigation on the structure and thermoelectric properties of CuTe binary compounds" by Shriparna Mukherjee et al., Dalton Trans., 2019, 48, 1040.

The Raman spectra of copper tellurides are nearly unknown. This is due not only to the difficulty in obtaining single-phase specimens, but also to the low inelastic light scattering efficiency of CuTe. To date, only the Raman spectrum of the vulcanite phase, CuTe, has been both measured and calculated by density functional theory.

Magnetic Force Microscopy Study of Multiscale Ion-Implanted Platinum in Silica Glass, Recorded by an Ultrafast Two-Wave Mixing Configuration.

This study explores magnetization exhibited by nanoscale platinum-based structures embedded in pure silica plates. A superposition of laser pulses in the samples produced periodic linear arrangements of micro-sized structures. The samples were integrated by PtO2 microstructures (PtOΣs) with dispersed Pt oxide nanoparticles in their surroundings.

On the stability of Cu Te polytypes: phase transitions, vibrational and electronic properties.

Based on the experimental structures reported for the Cu Te (1  ⩽  x  ⩽  2) system, a theoretical study on stability and phase transitions has been performed. Three theoretical structures derived from rickardite (CuTe) were considered to represent different Cu/Te ratios (1, 1.5 and 2).

Crystalline structure, electronic and lattice-dynamics properties of NbTe.

Layered-structure materials are currently relevant given their quasi-2D nature. Knowledge of their physical properties is currently of major interest. Niobium ditelluride possesses a monoclinic layered-structure with a distortion in the tellurium planes.

Vibrational and electrical properties of CuTe films: experimental data and first principle calculations.

Vibrational and electrical properties of sputtered films of the copper telluride system are presented. Despite of its technological importance in photovoltaics, the fundamental properties of copper tellurides are poorly understood. Films were deposited at 200 °C by rf sputtering from targets containing mixtures of copper and tellurium powders at nominal concentrations of CuTe, CuTe, CuTe and CuTe.

Segmentation and additive approach: A reliable technique to study noncovalent interactions of large molecules at the surface of single-wall carbon nanotubes.

This investigation explores a new protocol, named Segmentation and Additive approach (SAA), to study exohedral noncovalent functionalization of single-walled carbon nanotubes with large molecules, such as polymers and biomolecules, by segmenting the entire system into smaller units to reduce computational cost. A key criterion of the segmentation process is the preservation of the molecular structure responsible for stabilization of the entire system in smaller segments. Noncovalent interaction of linoleic acid (LA, C18 H32 O2 ), a fatty acid, at the surface of a (10,0) zigzag nanotube is considered for test purposes.

Lithium Adsorption on Graphene: From Isolated Adatoms to Metallic Sheets.

We have studied Li adsorption on graphene for Li concentrations ranging from about 1% to 50% by means of density functional theory calculations. At low adsorbant densities, we observe a strong ionic interaction characterized by a substantial charge transfer from the adatoms to the substrate. In this low concentration regime, the electronic density around the Li adatoms is well localized and does not contribute to the electronic behavior in the vicinity of the Fermi level.