The Effect of Degrees of Inversion on the Electronic Structure of Spinel NiCoO: A Density Functional Theory Study.

In this study, electronic structure calculations and Bader charge analysis have been completed on the inverse, intermediate, and normal spinel structures of NiCoO in both primitive and conventional cells, using density functional theory with Hubbard correction. Three spinel structures have been computed in the primitive cell, where the fully inverse spinel, 50% intermediate spinel, and normal spinel can be acquired by swapping Ni and Co atoms on tetrahedral and octahedral sites. Furthermore, NiCoO with different degrees of inversion in the conventional cells was also investigated, along with their doping energies.

LiSiOCl: A Hexagonal Argyrodite Based on Antiperovskite Layer Stacking.

A hexagonal analogue, LiSiOCl, of the cubic lithium argyrodite family of solid electrolytes is isolated by a computation-experiment approach. We show that the argyrodite structure is equivalent to the cubic antiperovskite solid electrolyte structure through anion site and vacancy ordering within a cubic stacking of two close-packed layers. Construction of models that assemble these layers with the combination of hexagonal and cubic stacking motifs, both well known in the large family of perovskite structural variants, followed by energy minimization identifies LiSiOCl as a stable candidate composition.

Multi-level climate change planning: An analysis of the Italian case.

As recognized by the Paris Climate Agreement of the United Nations Framework Convention on Climate Change (UNFCCC), local and subnational regions are crucial actors to achieve international mitigation and adaptation commitments. Scientific literature and empirical evidence point at multi-level climate governance as a crucial factor to engage subnational levels in the achievement of national and international objectives. This work focuses on the multi-level climate governance arrangements in Italy to investigate how Italian regions/provinces/cities are contributing to the achievement of national commitments.

Enhanced Spin-Orbit Coupling in Heavy Metals via Molecular Coupling.

5d metals are used in electronics because of their high spin-orbit coupling (SOC) leading to efficient spin-electric conversion. When C is grown on a metal, the electronic structure is altered due to hybridization and charge transfer. In this work, we measure the spin Hall magnetoresistance for Pt/C and Ta/C, finding that they are up to a factor of 6 higher than those for pristine metals, indicating a 20-60% increase in the spin Hall angle.

Indium Gallium Oxide Alloys: Electronic Structure, Optical Gap, Surface Space Charge, and Chemical Trends within Common-Cation Semiconductors.

The electronic and optical properties of (InGa)O alloys are highly tunable, giving rise to a myriad of applications including transparent conductors, transparent electronics, and solar-blind ultraviolet photodetectors. Here, we investigate these properties for a high quality pulsed laser deposited film which possesses a lateral cation composition gradient (0.01 ≤ ≤ 0.

Formulation and Characterization of Alginate-Based Membranes for the Potential Transdermal Delivery of Methotrexate.

The aim of this study is to obtain and characterize of alginate-based membranes, as well as to choose the most suitable membrane type for the transdermal release of methotrexate. The paper presents the synthesis of four types of membranes based on alginate to which are added other copolymers (Carbopol, Tween, and Polyvinylpyrrolidone) as well as other components with different roles. Membranes and binary mixtures made between the components used in membrane synthesis and methotrexate are analyzed by thermogravimetric techniques, FTIR and UV spectroscopic techniques as well as SEM.

Formation Mechanism of Multipurpose Silica Nanocapsules.

Core-shell structures containing active materials can be fabricated using almost infinite reactant combinations. A mechanism to describe their formation is therefore useful. In this work, nanoscale all-silica shell capsules with an aqueous core were fabricated by the HCl-catalyzed condensation of tetraethyl orthosilicate (TEOS), using Pickering emulsion templates.

Batch and Fixed-Bed Column Studies on Palladium Recovery from Acidic Solution by Modified MgSiO.

Effective recovery of palladium ions from acidic waste solutions is important due to palladium's intensive usage as a catalyst for different industrial processes and to the high price paid for its production from natural resources. In this paper, we test the ability of a new adsorbent, MgSiO functionalized by impregnation with DL-cysteine (cys), for palladium ion recovery from waste solutions. The Brunauer-Emmett-Teller (BET) surface area analysis, Barrett-Joyner-Halenda (BJH) pore size and volume analysis, scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy and Fourier-Transformed Infrared (FTIR) spectroscopy have been performed to characterize this material.

Density Functional Theory and Experimental Determination of Band Gaps and Lattice Parameters in Kesterite CuZnSn(SSe).

The structures and band gaps of copper-zinc-tin selenosulfides (CZTSSe) are investigated for a range of anion compositions through experimental analysis and complementary first-principles simulations. The band gap was found to be extremely sensitive to the Sn-anion bond length, with an almost linear correlation with the average Sn-anion bond length in the mixed anion phase CuZnSn(SSe). Therefore, an accurate prediction of band gaps using first-principles methods requires the accurate reproduction of the experimental bond lengths.

How Oxygen Exposure Improves the Back Contact and Performance of Antimony Selenide Solar Cells.

The improvement of antimony selenide solar cells by short-term air exposure is explained using complementary cell and material studies. We demonstrate that exposure to air yields a relative efficiency improvement of n-type SbSe solar cells of ca. 10% by oxidation of the back surface and a reduction in the back contact barrier height (measured by ) from 320 to 280 meV.

Alkaline Water Oxidation Using a Bimetallic Phospho-Boride Electrocatalyst.

New oxygen evolution reaction (OER) electrocatalysts based on low-cost elements, which set new benchmark levels of activity, are vital if water electrolysis is to be applied on a global scale. Herein, a low-cost bimetallic phospho-boride catalyst was developed that showed outstanding OER activity of approximately 195 mV to achieve 10 mA cm in alkaline water electrolysis, with a minimal catalyst loading of 0.3 mg cm .

Potential and pitfalls: On the use of transient absorption spectroscopy for in situ and operando studies of photoelectrodes.

Here, we discuss the application, advantages, and potential pitfalls of using transient UV/Vis (ultraviolet-visible) absorption spectroscopy to study photoelectrodes for water splitting. We revisit one of the most commonly studied water oxidation photoanodes (α-FeO) to provide commentary and guidelines on experiment design and data analysis for transient absorption (TA) studies of photoelectrodes within a photoelectrochemical cell. We also assess the applicability of such in situ TA studies to understand photoelectrodes under operating conditions.

Folding a Single-Molecule Junction.

Stimuli-responsive molecular junctions, where the conductance can be altered by an external perturbation, are an important class of nanoelectronic devices. These have recently attracted interest as large effects can be introduced through exploitation of quantum phenomena. We show here that significant changes in conductance can be attained as a molecule is repeatedly compressed and relaxed, resulting in molecular folding along a flexible fragment and cycling between an anti and a syn conformation.

Estimation on Fixed-Bed Column Parameters of Breakthrough Behaviors for Gold Recovery by Adsorption onto Modified/Functionalized Amberlite XAD7.

The objective of this paper was to evaluate the potential of a new adsorbent material to recover Au (III) from real wastewater, in a column with a fixed bed in a dynamic regime. The material was obtained through functionalization, by impregnation of the commercial resin, Amberlite XAD 7 type, with L-glutamic acid, which has active groups -NH and -COOH. The goal of the experiments was to follow the correlation of fixed-bed column specific adsorption parameters (the effluent volume, the amounts of adsorbent, heights of the adsorbent layer in column) with the time necessary to cross the column.

Vacancy-Ordered Double Perovskite CsTeI Thin Films for Optoelectronics.

Alternatives to lead- and tin-based perovskites for photovoltaics and optoelectronics are sought that do not suffer from the disadvantages of toxicity and low device efficiency of present-day materials. Here we report a study of the double perovskite CsTeI, which we have synthesized in the thin film form for the first time. Exhaustive trials concluded that spin coating CsI and TeI using an antisolvent method produced uniform films, confirmed as CsTeI by XRD with Rietveld analysis.

Crystal Structure and Stoichiometric Composition of Potassium-Intercalated Tetracene.

The products of the solid-state reactions between potassium metal and tetracene (K:Tetracene, 1:1, 1.5:1, and 2:1) are fully structurally characterized. Synchrotron X-ray powder diffraction shows that only KTetracene forms under the reaction conditions studied, with unreacted tetracene always present for < 2.

Microscopic Analysis of Interdiffusion and Void Formation in CdTeSe and CdTe Layers.

The use of CdSe layers has recently emerged as a route to improving CdTe photovoltaics through the formation of a CdTeSe (CST) phase. However, the extent of the Se diffusion and the influence it has on the CdTe grain structure has not been widely investigated. In this study, we used transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), and electron backscatter diffraction (EBSD) to investigate the impact of growing CdTe layers on three different window layer structures CdS, CdSe, and CdS/CdSe.

Crosslinked Polyimide and Reduced Graphene Oxide Composites as Long Cycle Life Positive Electrode for Lithium-Ion Cells.

Conjugated polymers with electrochemically active redox groups are a promising class of positive electrode material for lithium-ion batteries. However, most polymers, such as polyimides, possess low intrinsic conductivity, which results in low utilization of redox-active sites during charge cycling and, consequently, poor electrochemical performance. Here, it was shown that this limitation can be overcome by synthesizing polyimide composites (PIX) with reduced graphene oxide (rGO) using an in situ polycondensation reaction.

Laser-Generated Supranano Liquid Metal as Efficient Electron Mediator in Hybrid Perovskite Solar Cells.

Creating colloids of liquid metal with tailored dimensions has been of technical significance in nano-electronics while a challenge remains for generating supranano (<10 nm) liquid metal to unravel the mystery of their unconventional functionalities. Present study pioneers the technology of pulsed laser irradiation in liquid from a solid target to liquid, and yields liquid ternary nano-alloys that are laborious to obtain via wet-chemistry synthesis. Herein, the significant role of the supranano liquid metal on mediating the electrons at the grain boundaries of perovskite films, which are of significance to influence the carriers recombination and hysteresis in perovskite solar cells, is revealed.

Water Oxidation with Cobalt-Loaded Linear Conjugated Polymer Photocatalysts.

The first examples of linear conjugated organic polymer photocatalysts that produce oxygen from water after loading with cobalt and in the presence of an electron scavenger are reported. The oxygen evolution rates, which are higher than for related organic materials, can be rationalized by a combination of the thermodynamic driving force for water oxidation, the light absorption of the polymer, and the aqueous dispersibility of the relatively hydrophilic polymer particles. We also used transient absorption spectroscopy to study the best performing system and we found that fast oxidative quenching of the exciton occurs (picoseconds) in the presence of an electron scavenger, minimizing recombination.

Highly Stable Energy Capsules with Nano-SiO Pickering Shell for Thermal Energy Storage and Release.

Phase change materials (PCMs) store latent heat energy as they melt and release it upon freezing. However, they suffer from chemical instability and poor thermal conductivity, which can be improved by encapsulation. Here, we encapsulated a salt hydrate PCM (Mg(NO)·6HO) within all-silica nanocapsules using a Pickering emulsion template.

Water-Hydrogen-Polaron Coupling at Anatase TiO(101) Surfaces: A Hybrid Density Functional Theory Study.

Defects and water generally coexist on the surfaces of reducible metal oxides for heterogeneous photocatalysis in aqueous environments, which makes quantification and understanding of their coupling essential for development of practical solutions. Here we explore and quantify the coupling between water (HO)- and hydrogen (H)-induced electron-polarons on the TiO anatase (101) surface by means of first-principles simulations. Without HO, the hydrogen-induced electron-polaron localizes preferentially around the energetically favored subsurface H site.

Evidence for Self-healing Benign Grain Boundaries and a Highly Defective SbSe-CdS Interfacial Layer in SbSe Thin-Film Photovoltaics.

The crystal structure of SbSe gives rise to unique properties that cannot otherwise be achieved with conventional thin-film photovoltaic materials, such as CdTe or Cu(In,Ga)Se. It has previously been proposed that grain boundaries can be made benign provided only the weak van der Waals forces between the (SbSe) ribbons are disrupted. Here, it is shown that non-radiative recombination is suppressed even for grain boundaries cutting across the (SbSe) ribbons.

GeSe: Optical Spectroscopy and Theoretical Study of a van der Waals Solar Absorber.

The van der Waals material GeSe is a potential solar absorber, but its optoelectronic properties are not yet fully understood. Here, through a combined theoretical and experimental approach, the optoelectronic and structural properties of GeSe are determined. A fundamental absorption onset of 1.