Crystal structure and electronic properties of low-dimensional hexamethylenediaminium lead halide perovskites.

This work reports on hybrid hexamethylenediaminium lead halide perovskites. The materials were prepared using wet synthesis and the subsequent precipitation from aqueous solution. Structural and morphological charactarization studies show their high degree of crystallinity and phase purity.

Glass-Ceramic Synthesis of Cr-Substituted Strontium Hexaferrite Nanoparticles with Enhanced Coercivity.

Magnetically hard ferrites attract considerable interest due to their ability to maintain a high coercivity of nanosized particles and therefore show promising applications as nanomagnets ranging from magnetic recording to biomedicine. Herein, we report an approach to prepare nonsintered single-domain nanoparticles of chromium-substituted hexaferrite via crystallization of glass in the system SrO-FeO-CrO-BO. We have observed a formation of plate-like hexaferrite nanoparticles with diameters changing from 20 to 190 nm depending on the annealing temperature.

Cryochemically Processed LiMnNiCoO₄ (y = 0, 0.1) Cathode Materials for Li-Ion Batteries.

A new route for the preparation of nickel and cobalt substituted spinel cathode materials (LiMnCoNiO₄ and LiMnCoNiO₄) by freeze-drying of acetate precursors followed by heat treatment was suggested in the present work. The experimental conditions for the preparation single-phase material with small particle size were optimized. Single-phase spinel was formed by low-temperature annealing at 700 °C.

Effect of nanostructured carbon coatings on the electrochemical performance of LiNiMnO -based cathode materials.

Nanocomposites of LiNiMnO and amorphous carbon were obtained by the pyrolysis of linear and cross-linked poly(vinyl alcohol) (PVA) in presence of LiNiMnO . In the case of linear PVA, the formation of nanostructured carbon coatings on LiNiMnO particles is observed, while for cross-linked PVA islands of mesoporous carbon are located on the boundaries of LiNiMnO particles. The presence of the carbon framework leads to a decrease of the polarization upon cycling and of the charge transfer resistance and to an increase in the apparent Li diffusion coefficient from 10 cm·s (pure LiNiMnO ) to 10 cm·s.