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Efficient control of photons is enabled by hybridizing light with matter. The resulting light-matter quasi-particles can be readily programmed by manipulating either their photonic or matter constituents. Here, we hybridized infrared photons with graphene Dirac electrons to form surface plasmon polaritons (SPPs) and uncovered a previously unexplored means to control SPPs in structures with periodically modulated carrier density. In these periodic structures, common SPPs with continuous dispersion are transformed into Bloch polaritons with attendant discrete bands separated by bandgaps. We explored directional Bloch polaritons and steered their propagation by dialing the proper gate voltage. Fourier analysis of the near-field images corroborates that this on-demand nano-optics functionality is rooted in the polaritonic band structure. Our programmable polaritonic platform paves the way for the much-sought benefits of on-the-chip photonic circuits. 

Flexible and low-cost poly(ethylene oxide) (PEO)-based electrolytes are promising for all-solid-state Li-metal batteries because of their compatibility with a metallic lithium anode. However, the low room-temperature Li-ion conductivity of PEO solid electrolytes and severe lithium-dendrite growth limit their application in high-energy Li-metal batteries. Here we prepared a PEO/perovskite Li 3/8 Sr 7/16 Ta 3/4 Zr 1/4 O 3 composite electrolyte with a Li-ion conductivity of 5.4 × 10 −5 and 3.5 × 10 −4 S cm −1 at 25 and 45 °C, respectively; the strong interaction between the F − of TFSI − (bis-trifluoromethanesulfonimide) and the surface Ta 5+ of the perovskite improves the Li-ion transport at the PEO/perovskite interface. A symmetric Li/composite electrolyte/Li cell shows an excellent cyclability at a high current density up to 0.6 mA cm −2 . A solid electrolyte interphase layer formed in situ between the metallic lithium anode and the composite electrolyte suppresses lithium-dendrite formation and growth. All-solid-state Li|LiFePO 4 and high-voltage Li|LiNi 0.8 Mn 0.1 Co 0.1 O 2 batteries with the composite electrolyte have an impressive performance with high Coulombic efficiencies, small overpotentials, and good cycling stability. 

In this work, the Na–K liquid alloy with a charge selective interfacial layer is developed to achieve an impressively long cycling life with small overpotential on a sodium super‐ionic conductor solid‐state electrolyte (NASICON SSE). With this unique multi‐cation system as the platform, we further propose a unique model that contains a chemical decomposition domain and a kinetic decomposition domain for the interfacial stability model. Based on this model, two charge selection mechanisms are proposed with dynamic chemical kinetic equilibrium and electrochemical kinetics as the manners of control, respectively, and both are validated by the electrochemical measurements with microscopic and spectroscopic characterizations. This study provides an effective design for high‐energy‐density solid‐state battery with alkali Na–K anode, but also presents a novel approach to understand the interfacial chemical processes that could inspire and guide future designs.

 

In this work, the Na–K liquid alloy with a charge selective interfacial layer is developed to achieve an impressively long cycling life with small overpotential on a sodium super‐ionic conductor solid‐state electrolyte (NASICON SSE). With this unique multi‐cation system as the platform, we further propose a unique model that contains a chemical decomposition domain and a kinetic decomposition domain for the interfacial stability model. Based on this model, two charge selection mechanisms are proposed with dynamic chemical kinetic equilibrium and electrochemical kinetics as the manners of control, respectively, and both are validated by the electrochemical measurements with microscopic and spectroscopic characterizations. This study provides an effective design for high‐energy‐density solid‐state battery with alkali Na–K anode, but also presents a novel approach to understand the interfacial chemical processes that could inspire and guide future designs.