Heat and charge transport in H2O at ice-giant conditions from ab initio MD simulations

The impact of the inner structure and thermal history of planets on their observable features, such as luminosity or magnetic field, crucially depends on the poorly known heat and charge transport properties of their internal layers. The thermal and electric conductivities of different phases of water (liquid, solid, and super-ionic) occurring in the interior of ice giant planets, such as Uranus or Neptune, are evaluated from equilibrium ab initio molecular dynamics, leveraging recent progresses in the theory and data analysis of transport in extended systems.

Identifying the Role of A-Site Cations in Modulating Oxygen Capacity of Iron-Based Perovskite for Enhanced Chemical Looping Methane-to-Syngas Conversion

Suppressing coke deposition over reduced oxygen carriers, the key to breaking competing effects between oxygen supply and methane-to-syngas selectivity, is an important but challenging task for chemical looping partial oxidation technology. We report that A-site engineering of La1–xSrxFe0.8Al0.2O3 oxides significantly adjusts the oxygen capacity, which nearly triples from 1.0 mmol/g (x = 0.1) to 2.7 mmol/g (x = 0.5) with CO selectivity maintaining above 94%.

Achieving Fast and Durable Lithium Storage through Amorphous FeP Nanoparticles Encapsulated in Ultrathin 3D P-Doped Porous Carbon Nanosheets

Conversion-type transition-metal phosphide anode materials with high theoretical capacity usually suffer from low-rate capability and severe capacity decay, which are mainly caused by their inferior electronic conductivities and large volumetric variations together with the poor reversibility of discharge product (Li3P), impeding their practical applications.

Mechanistic Insight into the Framework Methylation of H-ZSM-5 for Varying Methanol Loadings and Si/Al Ratios Using First-Principles Molecular Dynamics Simulations

The methanol-to-hydrocarbon process is known to proceed autocatalytically in H-ZSM-5 after an induction period where framework methoxy species are formed. In this work, we provide mechanistic insight into the framework methylation within H-ZSM-5 at high methanol loadings and varying acid site densities by means of first-principles molecular dynamics simulations.

Tuning Electrical Conductance in Bilayer MoS2 through Defect-Mediated Interlayer Chemical Bonding

Interlayer interaction could substantially affect the electrical transport in transition metal dichalcogenides, serving as an effective way to control the device performance. However, it is still challenging to utilize interlayer interaction in weakly interlayer-coupled materials such as pristine MoS2 to realize layer-dependent tunable transport behavior.

Unit cell restricted Bloch functions basis for first-principle transport models: Theory and application

We present the theory and the application of a first-principle transport model employing a basis set obtained directly from the ab initio Bloch functions. We use a plane-wave density functional theory Hamiltonian and show that a judicious choice of the reduced basis set can effectively suppress the potentially thorny problem of the unphysical solutions. Our methodology enables ab initio transport simulations with a huge reduction of the size of the problem compared to the original ab initio formulation.

Symmetry Dictated Grain Boundary State in a Two-Dimensional Topological Insulator

Grain boundaries (GBs) are ubiquitous in solids and have been of central importance in understanding the nature of polycrystals. In addition to their classical roles, topological insulators (TIs) offer a chance to realize GBs hosting distinct topological states that can be controlled by their crystal symmetries. However, such roles of crystalline symmetry in two-dimensional (2D) TIs have not been definitively measured yet. Here, we present the first direct evidence of a symmetry-enforced metallic state along a GB in 1T′-MoTe2, a prototypical 2D TI.

Multi-Space Excitation as an Alternative to the Landauer Picture for Nonequilibrium Quantum Transport

While the Landauer viewpoint constitutes a modern basis to understand nanoscale electronic transport and to realize first‐principles implementations of the nonequilibrium Green's function (NEGF) formalism, seeking an alternative picture can be beneficial for the fundamental understanding and practical calculations of quantum transport processes.

Photoelectron spectra of alkali metal–ammonia microjets: From blue electrolyte to bronze metal

Liquid ammonia is unusual in its capacity to host electrons in stable solution, with vivid blue and bronze colors signifying the low- and high-concentration regimes, respectively. Buttersack et al. used photoelectron spectroscopy and accompanying theoretical simulations to track the precise energetic changes that ensued as steadily rising quantities of electrons were introduced by dissolved lithium, sodium, or potassium (see the Perspective by Isborn).