2D Self-Assembly of Large-Sized Inorganic Nanosheets Leading to Enhanced Power Factors in Earth-Abundant CuSbSe-Based Flexible Hybrid Films.

Fabrication of large-sized inorganic nanosheets is an efficient strategy to promote carrier transportation in flexible thermoelectric (TE) films. Herein, we report the self-assembly of large-sized CuSbSe nanosheets by using a Se nanowire template via wet chemical synthesis and then vacuum-assisted filter these plate-like microcrystals on nylon to prepare CuSbSe flexible thermoelectric (TE) hybrid films. SEM reveals that the as-synthesized CuSbSe powders by using Se nanowires as selenium sources presented 2D plate-like micron structures uniformly and tightly self-assembled by acute triangle-like nanoparticles.

Atomic-Scale Visualization and Quantification of Configurational Entropy in Relation to Thermal Conductivity: A Proof-of-Principle Study in -GeSbTe.

It remains a daunting task to quantify the configurational entropy of a material from atom-revolved electron microscopy images and correlate the results with the material's lattice thermal conductivity, which strides across statics, dynamics, and thermal transport of crystal lattice over orders of magnitudes in length and time. Here, a proof-of-principle study of atomic-scale visualization and quantification of configurational entropy in relation to thermal conductivity in single crystalline trigonal GeSbTe (aka -GeSbTe) with native atomic site disorder is reported. A concerted effort of large -GeSbTe single crystal growth, in-lab developed analysis procedure of atomic column intensity, the visualization and quantification of configurational entropy including corresponding modulation, and thermal transport measurements enable an entropic "bottom-up" perspective to the lattice thermal conductivity of -GeSbTe.

A Spectroscopic Study of the Insulator-Metal Transition in Liquid Hydrogen and Deuterium.

The insulator-to-metal transition in dense fluid hydrogen is an essential phenomenon in the study of gas giant planetary interiors and the physical and chemical behavior of highly compressed condensed matter. Using direct fast laser spectroscopy techniques to probe hydrogen and deuterium precompressed in a diamond anvil cell and laser heated on microsecond timescales, an onset of metal-like reflectance is observed in the visible spectral range at >150 GPa and ≥ 3000 K. The reflectance increases rapidly with decreasing photon energy indicating free-electron metallic behavior with a plasma edge in the visible spectral range at high temperatures.

Superconductivity and Charge Density Wave in ZrTe3-xSex.

Charge density wave (CDW), the periodic modulation of the electronic charge density, will open a gap on the Fermi surface that commonly leads to decreased or vanishing conductivity. On the other hand superconductivity, a commonly believed competing order, features a Fermi surface gap that results in infinite conductivity. Here we report that superconductivity emerges upon Se doping in CDW conductor ZrTe3 when the long range CDW order is gradually suppressed.