Single-Crystal P2-NaMnNiO Cathode Material with Improved Cycling Stability for Sodium-Ion Batteries.

Layered oxides constitute one of the most promising cathode materials classes for large-scale sodium-ion batteries because of their high specific capacity, scalable synthesis, and low cost. However, their practical use is limited by their low energy density, physicochemical instability, and poor cycling stability. Aiming to mitigate these shortcomings, in this work, we synthesized polycrystalline (PC) and single-crystal (SC) P2-type NaMnNiO (NMNO) cathode materials through a solid-state route and evaluated their physicochemical and electrochemical performance.

Improving rechargeable magnesium batteries through dual cation co-intercalation strategy.

The development of competitive rechargeable Mg batteries is hindered by the poor mobility of divalent Mg ions in cathode host materials. In this work, we explore the dual cation co-intercalation strategy to mitigate the sluggishness of Mg in model TiS material. The strategy involves pairing Mg with Li or Na in dual-salt electrolytes in order to exploit the faster mobility of the latter with the aim to reach better electrochemical performance.

Polarization induced control of optical trap potentials in binary liquids.

We illustrate control of a polarized laser optical trapping potential landscape through the nonideal mixing of binary liquids. The inherent trapping potential asymmetry (ITPA) present in the trapping region results from the asymmetric intensity distribution in focal volume due to the high numerical aperture objective lens. Experimentally, we show that this ITPA effect can be modified and/or removed by the use of binary liquid mixtures.

Measurement of pure optical nonlinearity in carbon disulfide with a high-repetition-rate femtosecond laser.

Using the close-aperture Z-scan technique, the pure nonlinear refractive index (n) of carbon disulfide is measured with a 76 MHz repetition rate femtosecond laser. Strong interference of thermal effects exists with high-repetition-rate lasers that result in negative values of n. We remove the thermal effect completely by continuously increasing the sample flow rate (F) in a sample cell as indicated by the change in sign of n from negative to positive.

Unusual behavior of thermal lens in alcohols.

We use a femtosecond pump-probe Z-scan technique to measure the thermal lens (TL) signal in a homologous series of primary alcohols. The trend in these experimentally measured TL signals deviates in a counterintuitive manner from the ones calculated using theoretical models that are only based on the macroscopic parameters. Introspection shows that the present TL theories are based on heat conduction for low absorbing samples without considering any convective mode of heat transfer.