Spinel-Type MgMnO Nanoplates with Vanadate Coating for a Positive Electrode of Magnesium Rechargeable Batteries.

Spinel-type MgMnO nanoplates ∼10 nm thick were prepared as a positive electrode for magnesium rechargeable batteries by the transformation of metal hydroxide nanoplates. Homogeneous coating with a vanadate layer thinner than 3 nm was achieved on the spinel oxide nanoplates via coverage of the precursor and subsequent mild calcination. We found that the spinel oxide nanoplates with the homogeneous coating exhibit improved electrochemical properties, such as discharge potential, capacity, and cyclability, due to the enhanced insertion and extraction of magnesium ions and suppressed decomposition of electrolytes.

Modifications in coordination structure of Mg[TFSA]-based supporting salts for high-voltage magnesium rechargeable batteries.

To achieve a sustainable-energy society in the future, next-generation highly efficient energy storage technologies, particularly those based on multivalent metal negative electrodes, are urgently required to be developed. Magnesium rechargeable batteries (MRBs) are promising options owing to the many advantageous chemical and electrochemical properties of magnesium. However, the substantially low working voltage of sulfur-based positive electrodes may hinder MRBs in becoming alternatives to current Li-ion batteries.

Oscillatory growth for twisting crystals.

We demonstrate the oscillatory phenomenon for the twisting growth of a triclinic crystal through in situ observation of the concentration field around the growing tip of a needle by high-resolution phase-shift interferometry.