Lithium metal batteries (LMB) are vital devices for high-energy-density energy storage, but Li metal anode is highly reactive with electrolyte and forms uncontrolled dendrite that can cause undesirable parasitic reactions thus poor cycling stability and raise safety concerns. Despite remarkable progress made to partly solve these issues, the Li metal still plate at the electrode/electrolyte interface where the parasitic reactions and dendrite formation invariably occur. Here we demonstrate the inwardgrowth plating of Li into a metal foil while avoiding surface deposition, which is driven by the reversible solid-solution based alloy phase change. Lithiation of the solid solution alloy phase facilitates the freshly generated Li atoms at the surface to sink into the foil, while the reversible alloy phase change is companied by the dealloying reaction during delithiation, which extracts Li atoms from inside of the foil. The yielded dendrite free Li anode produces an enhanced Coulombic efficiency of 99.5  0.2% with a reversible capacity of 1660 mA h g -1 (3.3 mA h cm -2 ).

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The extraordinary optical properties of surface plasmons in metal nanostructures provide the possibilities to enhance and accelerate the spontaneous emission, and manipulate the decay and emission processes of quantum emitters. The extremely small mode volume of plasmonic nanocavities also benefits the realization of plasmon-exciton strong coupling. Here, the progress on the study of plasmon modified spontaneous emission and plasmon-exciton strong coupling are reviewed. The fundamentals of surface plasmons and quantum emitters, and the methods for assembling coupling systems of plasmonic nanostructures and quantum emitters are first introduced. Then the major aspects of plasmon modified spontaneous emission, including emission intensity, lifetime, spectral profile, direction, polarization, and energy transfer are reviewed. The coupling of quantum emitters and plasmonic waveguides is then discussed. Next, the developments of strong coupling between plasmonic structures and various quantum emitters are reviewed. Finally a few applications are highlighted followed by conclusions and outlook.

Optical nanoantennas can efficiently harvest electromagnetic energy from nanoscale space and boost the local radiation to the far field. The dielectric-metal nanogap is a novel design that can help to overcome the core issue of optical loss in all-metal nanostructures while enabling photon density of states larger than that in all-dielectric counterparts. This article reports that a crystalline spherical silicon nanoparticle on metal film (SiNPoM) nanoantenna can largely enhance the spontaneous emission intensity of quantum dots by an area-normalized factor of 69 and the decay rate by 42-fold compared with quantum dots on glass. A high total quantum efficiency of over 80%, including ~20% for far-field radiation and ~60% for surface plasmon polaritons, is obtained in simulation. Thanks to not only the low optical loss in dielectric nanoparticles but also the appropriate gap thickness which weakens the non-radiative decay due to the quenching from metal. Mie resonant modes additionally provide the flexible control of far-field emission patterns. Such a simple optical nanoantenna can be combined with various nanoscale optical emitters and easily extended to form large area metasurfaces functioning as active regions in light-emitting devices in applications such as advanced display, wireless optical communication, and quantum technology.

Inefficient and wide‐angle emission as well as low emission rate of optical nanoemitters (such as quantum dots) have been strongly limiting their practical applications in next‐generation nanophotonic devices, such as nanoscale light‐emitting diodes (LEDs) and on‐chip single photon sources. Optical nanoantennas provide a promising way to deal with these challenges. Yet, there has been no solution that can overcome these drawbacks simultaneously on a single device. Here, a hybrid plasmonic nanoantenna consisting of a silver nanocube positioned at the center of a gold concentric‐ring structure is proposed, which can simultaneously enhance the emission directionality and decay rate of quantum dots embedded in the nanogap beneath the nanocube while maintaining high quantum efficiency. Coupling quantum dots to this nanoantenna can result in 60% of the emitted photons collected by the first lens with a numerical aperture (NA) of 0.5 and 21% for a NA of 0.12. The total emission intensity and decay rate are enhanced by 121‐fold and 424‐fold, respectively, compared with quantum dots on a glass substrate. A high quantum efficiency above 50% is obtained in simulation. This novel platform can be applied to enhance various types of optical nanoemitters and to develop high‐speed directional nano‐LEDs and single photon sources.

In recent years, triazolylidene carbenes have come to the forefront as important organocatalysts for a wide range of reactions. The fundamental properties of these species, however, remain largely unknown. Herein, the gas phase acidities have been measured and calculated for a series of triazolium cations (the conjugate acids of the triazolylidene carbenes) that have not been heretofore examined in vacuo. The results are discussed in the context of these species as catalysts. We find correlations between the gas phase acidity and selectivity in two Umpolung reactions catalyzed by these species; such correlations are the first of their kind. We are able to use these linear correlations to improve reaction enantioselectivity. These results establish the possibility of using these thermochemical properties to predict reactivity in related transformations.

The Binding Energy Distribution Analysis Method (BEDAM) protocol has been employed as part of the SAMPL4 blind challenge to predict the binding free energies of a set of octa-acid host-guest complexes. The resulting predictions were consistently judged as some of the most accurate predictions in this category of the SAMPL4 challenge in terms of quantitative accuracy and statistical correlation relative to the experimental values, which were not known at the time the predictions were made. The work has been conducted as part of a hands-on graduate class laboratory session. Collectively the students, aided by automated setup and analysis tools, performed the bulk of the calculations and the numerical and structural analysis. The success of the experiment confirms the reliability of the BEDAM methodology and it shows that physics-based atomistic binding free energy estimation models, when properly streamlined and automated, can be successfully employed by non-specialists.

Uncovering the physics behind the electrical manipulation of low-dimensional magnetic materials remains a fundamental issue in practical application of nanoscale spintronics. Here, we propose a strategy to transform A-type antiferromagnetic (AFM) semiconductors into asymmetric AFM unipolar or bipolar magnetic semiconductors by applying perpendicular electric fields in van der Waals bilayer systems. Electric fields lifting energy levels of electrons within same spin channel from consistent layers in opposite direction enables unipolar magnetic semiconductor, whereas electrons within opposite spin channel enable bipolar magnetic semiconductor. A comprehensive study demonstrates this discrepancy originates from spatial distributions of spin density of valence band and conduction band edges in two layers of systems. The electric field induced unipolar or bipolar magnetic semiconducting behavior represents great potential of nanoscale AFM spintronics for information storage and processing.