Tailoring photocatalytic water splitting activity of boron-thiophene polymer through pore size engineering.

Taking into account the electron-rich and visible light response of thiophene, first-principles calculations have been carried out to explore the photocatalytic activity of donor-acceptor polymers incorporating thiophene and boron. Honeycomb-kagome boron-thiophene (BTP) polymers with varying numbers of thiophene units and fixed B center atoms are direct bandgap semiconductors with tunable bandgaps ranging from 2.41 to 1.

Ultrathin positively charged electrode skin for durable anion-intercalation battery chemistries.

The anion-intercalation chemistries of graphite have the potential to construct batteries with promising energy and power breakthroughs. Here, we report the use of an ultrathin, positively charged two-dimensional poly(pyridinium salt) membrane (C2DP) as the graphite electrode skin to overcome the critical durability problem. Large-area C2DP enables the conformal coating on the graphite electrode, remarkably alleviating the electrolyte.

Sulfide-Bridged Covalent Quinoxaline Frameworks for Lithium-Organosulfide Batteries.

The chelating ability of quinoxaline cores and the redox activity of organosulfide bridges in layered covalent organic frameworks (COFs) offer dual active sites for reversible lithium (Li)-storage. The designed COFs combining these properties feature disulfide and polysulfide-bridged networks showcasing an intriguing Li-storage mechanism, which can be considered as a lithium-organosulfide (Li-OrS) battery. The experimental-computational elucidation of three quinoxaline COFs containing systematically enhanced sulfur atoms in sulfide bridging demonstrates fast kinetics during Li interactions with the quinoxaline core.

Cation-selective two-dimensional polyimine membranes for high-performance osmotic energy conversion.

Two-dimensional (2D) membranes are emerging candidates for osmotic energy conversion. However, the trade-off between ion selectivity and conductivity remains the key bottleneck. Here we demonstrate a fully crystalline imine-based 2D polymer (2DPI) membrane capable of combining excellent ionic conductivity and high selectivity for osmotic energy conversion.

Porous Dithiine-Linked Covalent Organic Framework as a Dynamic Platform for Covalent Polysulfide Anchoring in Lithium-Sulfur Battery Cathodes.

Dithiine linkage formation via a dynamic and self-correcting nucleophilic aromatic substitution reaction enables the de novo synthesis of a porous thianthrene-based two-dimensional covalent organic framework (COF). For the first time, this organo-sulfur moiety is integrated as a structural building block into a crystalline layered COF. The structure of the new material deviates from the typical planar interlayer π-stacking of the COF to form undulated layers caused by bending along the C-S-C bridge, without loss of aromaticity and crystallinity of the overall COF structure.

Identification of Non-Carbonaceous Cathodes in Al Batteries: Potential Applicability of Black and Blue Phosphorene Monolayers.

In the present era of growing energy demands, low-dimensional materials are emerging as the suitable choices for energy storage due to their excellent ion transport properties, improved reversible capacity, fine rate performance and good cycling stability. In this context, we have investigated the applicability of black and blue phosphorene monolayers as potential cathodes for Al batteries. Both black and blue phosphorene monolayers show similar electrochemical behavior as that of experimentally reported graphite with a charge transfer from the surface in order to bind the tetrahedral geometry of AlCl during the charging process.

Role of Dimensionality for Photocatalytic Water Splitting: CdS Nanotube versus Bulk Structure.

Using state-of-the-art density functional theoretical calculations, we have modelled a facetted CdS nanotube (NT) catalyst for photocatalytic water splitting. The overall photocatalytic activity of the CdS photocatalyst has been predicted based on the electronic structures, band edge alignment, and overpotential calculations. For comparisons, we have also investigated the water splitting process over bulk CdS.

Ferromagnetism in magnesium chloride monolayer with an unusually large spin-up gap.

The primary research target of the rapidly evolving spintronic industry is to design highly efficient novel materials that consume very low power and operate with high speed. Main group based ferromagnetic half-metallic materials are very promising due to their long spin-relaxation time. In recent years, the discovery of superconducting state with high critical temperature in a magnesium based system (MgB) invigorated researchers due to its simple crystal structure and intriguing results, leading to its use as a good material for large scale application in electronic devices.

High-energy-density dual-ion battery for stationary storage of electricity using concentrated potassium fluorosulfonylimide.

Graphite dual-ion batteries represent a potential battery concept for large-scale stationary storage of electricity, especially when constructed free of lithium and other chemical elements with limited natural reserves. Owing to their non-rocking-chair operation mechanism, however, the practical deployment of graphite dual-ion batteries is inherently limited by the need for large quantities of electrolyte solutions as reservoirs of all ions that are needed for complete charge and discharge of the electrodes. Thus far, lithium-free graphite dual-ion batteries have employed moderately concentrated electrolyte solutions (0.

First-Principles Study of Magnesium Peroxide Nucleation for Mg-Air Battery.

Recently, rechargeable non-aqueous Mg-air batteries have gained a lot of interest as the next-generation energy storage device due to the high theoretical volumetric density (3832 Ah L for Mg anode vs. 2062 Ah L for Li), low cost and safety. The field of Mg-air batteries is in the initial stage of development having a limited number of experimental and theoretical reports, in which mainly a carbon cathode is used; however, the information regarding the structural form of carbon is still missing.

A Computational Study of a Single-Walled Carbon-Nanotube-Based Ultrafast High-Capacity Aluminum Battery.

Exploring suitable electrode materials is a fundamental step toward developing Al batteries with enhanced performance. In this work, we explore using density functional theory calculations the feasibility of single-walled carbon nanotubes (SWNTs) as a cathode material for Al batteries. Carbon nanotubes with hollow structures and large surface area are able to overcome the difficulty of activating the opening of interlayer spaces as observed in graphite electrode during the first intercalation cycle.

The staging mechanism of AlCl intercalation in a graphite electrode for an aluminium-ion battery.

Identifying a suitable electrode material with desirable electrochemical properties remains a primary challenge for rechargeable Al-ion batteries. Recently an ultrafast rechargeable Al-ion battery was reported with high charge/discharge rate, (relatively) high discharge voltage and high capacity that uses a graphite-based cathode. Using calculations from first-principles, we have investigated the staging mechanism of AlCl intercalation into bulk graphite and evaluated the stability, specific capacity and voltage profile of AlCl intercalated compounds.